Patent Publication Number: US-11638852-B2

Title: Portable devices for exercising muscles in the ankle, foot, and/or leg, and related methods

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. national stage application under 35 U.S.C. § 371(c) of International Application No. PCT/US2019/015030, filed Jan. 24, 2019, which claims priority to U.S. Provisional Patent Application No. 62/653,906, filed Apr. 6, 2018 and entitled “Portable Devices for Exercising Muscles in the Ankle, Foot, and/or Leg, and Related Methods,” and to U.S. Provisional Patent Application No. 62/731,647, filed Sep. 14, 2018 and entitled “Portable Devices for Exercising Muscles in the Ankle, Foot, and/or Leg, and Related Methods,” the entire content of each of which is incorporated by reference herein. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to portable devices for exercising muscles in the ankle, foot, and/or leg, and related methods. More particularly, the present disclosure relates to portable devices, and related methods, for exercising muscles in the ankle, foot, and/or leg of a user to increase blood circulation, which may, for example, assist in preventing venous thromboembolism. 
     INTRODUCTION 
     The section headings used herein are for organizational purposes only and are not to be construed as limiting the subject matter described in any way. 
     Venous thromboembolism (VTE) occurs when red blood cells, fibrin and, to a lesser extent, platelets and leukocytes, form a mass (i.e., clot) within an intact vein. The thrombus (i.e., blood clot) is referred to as a deep venous thrombosis (DVT) when formed within the deep veins of the legs or in the pelvic veins. A pulmonary embolism (PE) results when a piece of thrombus detaches from a vein wall, travels to the lungs, and lodges within the pulmonary arteries. 
     VTE is often a concern in situations where an individual is immobile and/or relatively nonambulatory for a relatively long period of time, such as, for example, during hospitalization, after surgery, during pregnancy and/or in the postpartum period, while traveling (e.g., in a car, plane and/or train), at work, and/or in a more sedentary lifestyle (e.g., the elderly and/or obese). Blood returning to the heart does so through veins. Large veins, such as those found in the legs, lie near and between muscles and contain valves that maintain the flow of blood in the direction of the heart by preventing backflow and stasis. The contraction of these muscles (e.g., through walking) forces the blood through the veins in the direction of the heart, usually against the force of gravity, thereby preventing blood from accumulating in the extremities. If these muscles are not used and/or minimally (e.g., infrequently) used for an extended period of time, however, the lower limbs may swell with stationary blood, greatly increasing the risk of VTE. 
     Because of this potential danger, preventative measures against VTE have become standard, for example, in prolonged hospitalizations and postoperative care. Consequently, in conjunction with early ambulation, a number of prophylaxis devices have been developed to help prevent VTE, including, for example, graduated compression stockings, intermittent pneumatic compression devices, and pneumatic compression devices. Such compressive techniques, however, fail to treat and articulate a patient&#39;s ankle and/or knee joints, or otherwise contract the ankle, foot and/or leg (e.g., calf) muscles. These devices and methods, therefore have limited exercise and therapy capabilities, and are generally impractical for use outside of a hospital setting. 
     Various additional exercise devices serve to articulate a patient&#39;s joints, thereby providing joint therapy while contracting the muscles of the ankle, foot, and/or leg to prevent blood from accumulating in the lower extremities of the body. Such devices, however, often fail to allow both full flexion and extension of a user&#39;s ankle, to provide both plantar flexion (i.e., movement which increases the approximate 90° angle between the front part of the foot and the shin, thereby contracting the calf muscle) and dorsiflexion motion (i.e., movement which decreases the angle between the front part of the foot and the shin, thereby stretching the calf muscle). Furthermore, many of these devices are bulky, cumbersome, complex and expensive; being impractical for use during transition care or between care locations, or for use by other VTE at-risk groups, such as, for example, travelers. 
     Due to growing concerns over the continued prevalence of VTE related medical cases, it may be desirable to provide a relatively simple, inexpensive device and method with full exercise and therapy capabilities, which allows for full flexion and extension of a user&#39;s ankle joint, while also being lightweight and compact. It also may be desirable to provide a device that is portable, being useful for all VTE at-risk individuals. 
     SUMMARY 
     The present disclosure may solve one or more of the above-mentioned problems and/or may demonstrate one or more of the above-mentioned desirable features. Other features and/or advantages may become apparent from the description that follows. 
     In accordance with various exemplary embodiments of the present disclosure, a portable exercise device includes a pedal spaced away from and pivotably connected to a base and having a neutral position relative to a pivot axis. The pedal is configured to rotate about the pivot axis in a first direction toward the base and in a second direction, opposite the first direction, toward the base. The portable exercise device also includes a resistance mechanism configured to exert a force on the pedal about the pivot axis in a direction opposite to the respective direction of rotation of the pedal about the pivot axis. The portable exercise device is movable between an open, in-use configuration, where the pedal is disposed in the neutral position to receive a foot of a user and spaced away from the base, and a closed configuration, where the pedal is adjacent the base. 
     In accordance with various additional exemplary embodiments of the present disclosure, a portable exercise device includes at least one pedal pivotably connected to a base and having a neutral position relative to a pivot axis. The pedal comprises a toe end portion and a heel end portion, wherein the pivot axis is below the pedal and is approximately centered between the toe end portion and the heel end portion. The pedal is configured to rotate about the pivot axis in a first direction away from the neutral position in which the toe end portion moves toward the base and in a second direction away from the neutral position in which the heel end portion moves toward the base, such that rotation of the pedal in the first direction and the second direction, sequentially, moves the pedal in a rocking motion. The portable exercise device also includes a resistance mechanism configured to exert a force on the pedal about the pivot axis in a direction opposite to the respective first and second directions of rotation of the pedal about the pivot axis. 
     In accordance with various further exemplary embodiments of the present disclosure, a method for exercising muscles in an ankle, foot, and/or leg of a user includes positioning a foot of a user onto a pedal of an exercise device. The pedal is spaced away from and pivotably connected to a base of the device and has a neutral position relative to a pivot axis. The method also includes rotating the pedal with the foot in a first direction about the pivot axis to move a first end of the pedal toward the base. The method further includes resisting a pivoting motion of the pedal with a force exerted against a second end of the pedal in a direction opposite to the first direction of rotation. 
     In accordance with various further exemplary embodiments of the present disclosure, a method for exercising muscles in an ankle, foot, and/or leg of a user, comprises increasing fluid circulation velocity within body tissue by, with a foot of a user positioned on a pedal of an exercise device, the pedal being spaced away from and pivotably connected to a base of the device and having a neutral position relative to a pivot axis, rotating the pedal with the foot in a first direction about the pivot axis to move a first end of the pedal toward the base and resisting a pivoting motion of the pedal with a force exerted against a second end of the pedal in a direction opposite to the first direction of rotation. The method further includes rotating the pedal with the foot in a second direction, opposite to the first direction, to move the second end of the pedal toward the base and resisting the rotation in the second direction with a force exerted against the first end of the pedal in a direction opposite to the second direction of rotation. 
     Additional objects and advantages will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present disclosure. The objects and advantages may be realized and attained by means of the elements and combinations particularly pointed out in the appended claims and their equivalents. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure can be understood from the following detailed description either alone or together with the accompanying drawings. The drawings are included to provide a further understanding, and are incorporated in and constitute a part of this specification. The drawings illustrate one or more exemplary embodiments of the present disclosure and together with the description serve to explain various principles and operations. 
         FIG.  1    is a perspective top, front view of an exemplary embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  2    is a perspective side, back view of the device of  FIG.  1    in the open configuration; 
         FIG.  3    is a side view of the device of  FIG.  1    in the open configuration; 
         FIG.  4    is a front view of the device of  FIG.  1    in the open configuration; 
         FIG.  5    is a back view of the device of  FIG.  1    in the open configuration; 
         FIG.  6    is a side view of the device of  FIG.  1    in the open configuration, showing a user&#39;s foot strapped to the device for use in a sitting position; 
         FIG.  7    is a side view of the device of  FIG.  1    in the open configuration, showing a user&#39;s foot strapped to the device for use in a supine position. 
         FIG.  8    is a perspective top, front view of the device of  FIG.  1    in a closed configuration; 
         FIG.  9    is a perspective side, back view of the device of  FIG.  1    in the closed configuration; 
         FIG.  10    is a side view of the device of  FIG.  1    in the closed configuration; 
         FIG.  11    is a front view of the device of  FIG.  1    in the closed configuration; 
         FIG.  12    is a back view of the device of  FIG.  1    in the closed configuration; 
         FIG.  13 A  is a perspective side view of another embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure, showing a user rotating a pedal of the device in a first direction; 
         FIG.  13 B  is a perspective side view of the device of  FIG.  12 B  in the open configuration, showing a user rotating a pedal of the device in a second direction; 
         FIG.  14    is a diagram of an exemplary range of motion of the portable exercise devices in accordance with the present disclosure; 
         FIG.  15    is a perspective view of another embodiment of a portable device, in an open configuration, in accordance with the present disclosure; 
         FIG.  16    is a perspective view of another embodiment of a portable device, in an open configuration, in accordance with the present disclosure; 
         FIG.  17    is a perspective view of yet another embodiment of a portable device, in an open configuration, in accordance with the present disclosure; 
         FIG.  18    is a perspective top view of yet another embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  19    is a perspective side, front view on the device of  FIG.  18    in the open configuration; 
         FIG.  20    is a perspective side view of the device of  FIG.  18    in the open configuration; 
         FIG.  21    is a perspective side, top view of the device of  FIG.  18    in a closed configuration; 
         FIG.  22    is a perspective top, front view of another embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  23    is a perspective top, front view of yet another embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  24    is a perspective top, front view of an additional embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  25    is a perspective top, front view of another embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  26    is a perspective top, front view of the device of  FIG.  25    in a closed configuration; 
         FIG.  27    is a top, front view of the device of  FIG.  25    in a closed configuration and partially inserted into an exemplary pouch in accordance with the present disclosure; 
         FIG.  28    is a perspective top, front view of another embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  29    is a perspective top, front view of the device of  FIG.  28    in a closed configuration; 
         FIG.  30    is a perspective top, front view of another embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  31    is a perspective top, front view of the device of  FIG.  30    in a closed configuration; 
         FIG.  32    is a graph illustrating the average percentage increase in blood flow over time during use of an exercise device in accordance with the present disclosure; 
         FIG.  33    is a partial, perspective top, front view of another embodiment of a portable exercise device in accordance with the present disclosure; 
         FIG.  34    is a side view of another exemplary embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  35    is a side view of the device of  FIG.  34    in a closed configuration; 
         FIG.  36    is a perspective top, front view of another embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  37    is a perspective top, back view of the device of  FIG.  36    in a closed configuration; 
         FIG.  38    is a partially exploded, perspective top, back view of the device of  FIG.  36    in the closed configuration; 
         FIG.  39    is a perspective bottom view of the device of  FIG.  36    in the closed configuration; 
         FIG.  40    is a perspective top, front view of another embodiment of a portable exercise device, in an open configuration, in accordance with the present disclosure; 
         FIG.  41    is a perspective top, front view of the device of  FIG.  40    in a closed configuration; and 
         FIG.  42    is a perspective bottom view of the device of  FIG.  40    in the closed configuration. 
     
    
    
     DESCRIPTION OF VARIOUS EXEMPLARY EMBODIMENTS 
     Various conventional thromboprophylaxis techniques typically rely on devices that are cumbersome, complex, and/or expensive. Consequently, such devices are generally impractical for use during transition care or between care locations, or for use by other VTE vulnerable groups, such as, for example, expectant mothers, travelers and/or other individuals sitting for extended periods. To increase thromboprophylaxis utilization, various exemplary embodiments of the present disclosure provide portable devices for exercising an ankle, foot and/or leg, and methods of using such devices, that provide simple and relatively inexpensive prophylaxis by providing full flexion and extension of the ankle joint to increase circulation in the lower extremities of the body. Increasing circulation may include increasing circulation in body tissues. Movement of bodily fluids, including blood, lymph, and/or interstitial fluids may be achieved through practice of the disclosed methods and use of the disclosed devices. The increased circulation may be found in one or more of blood vessels, the lymphatic system, muscles, interstitial spaces, capillaries and surrounding body tissues. In addition to the movement of fluids through ankle flexion and extension, the pressure applied to the sole of the foot during the exercise, i.e., plantar pressure, also contributes to movement of fluid through the body tissue and to an increase in circulation of bodily fluids. 
     In various exemplary embodiments, portable exercise devices for exercising an ankle, foot and/or leg, and related methods, use at least one pedal that is pivotably connected to a base about a pivot axis. The pedal has a neutral position relative to the pivot axis and is generally positioned such that the pivot axis is centrally located along a length of the pedal. When the pedal is in the neutral position, the pedal is substantially parallel to the base and there is a space between the pedal and the base. In this manner, the pedal is configured to rotate about the pivot axis in a first direction away from the neutral position and toward the base (where a first end of the pedal moves toward the base) and in a second direction away from the neutral direction and toward the base (where a second end of the pedal moves toward the base), wherein the second direction is opposite the first direction. 
     The devices and methods also use a resistance mechanism that is configured to exert a force on the pedal about the pivot axis in a direction opposite to a respective direction of rotation of the pedal about the pivot axis. For example, in accordance with various embodiments, to exercise the ankle, foot, and/or leg of the user, as explained further below, the force exerted by the resistance mechanism is configured to provide a passive resistance to the rotational movement of the pedal. In other words, the resistance mechanism is configured to provide a passive resistance against the rotation of the pedal throughout a full range of ankle flexion and ankle extension. 
     In accordance with the present disclosure, a pivot axis of the device may be located at a point configured to be positioned below a user&#39;s ankle during use. In some embodiments, the pivot axis of the device may be located at a point configured to be positioned below a central portion of a user&#39;s foot during use, such that the user&#39;s foot undergoes a rocking motion as it moves through a full range of ankle flexion and ankle extension. 
     As used herein, the term “full range of ankle flexion and ankle extension” refers to the complete range of motion that the joints of a healthy user&#39;s ankle may undergo. In accordance with exemplary embodiments of the present disclosure, as illustrated in  FIG.  14   , a full range of ankle flexion and extension includes about 75 degrees of plantar flexion motion p (e.g., rotation ranging from about neutral to 75 degrees); and about 60 degrees of dorsiflexion motion d (e.g., rotation ranging from about neutral to −60 degrees). It will be understood, however, that the ambulatory ability of a user may be limited, and that, accordingly, the range of ankle flexion and ankle extension of each individual user may vary and be somewhat to significantly less than the full range of ankle flexion and ankle extension. 
     Accordingly, as illustrated in the exemplary embodiments shown in the drawings, a portable exercise device in accordance with the present disclosure has a simple configuration, which includes three main parts: 1) a base, 2) at least one pedal pivotably connected to the base, and 3) a resistance mechanism which is configured to resist the rotation of the pedal with respect to a neutral position in at least two opposite directions. Furthermore, for portability, devices in accordance with the present disclosure are adjustable to at least two configurations: 1) an open, in use configuration, wherein the pedal is spaced away from the base to enable the pedal to rotate relative to the base, the pedal being disposed in the neutral position to receive a foot of a user, and 2) a closed configuration, wherein the pedal is adjacent to, collapsed against, or otherwise positioned near the base to minimize a space between the pedal and the base, and thereby the size of the device. The closed configuration does not permit use of the device but is configured to facilitate storage and/or transport of the device. 
       FIGS.  1 - 7    illustrate an exemplary exercise device  100 , in accordance with an exemplary embodiment of the present disclosure, in an open, in use configuration.  FIGS.  8 - 12    show the exercise device  100  in a closed configuration. As shown in  FIGS.  1 - 12   , the exercise device  100  includes a base  102 , a pedal  101 , and a resistance mechanism  103 , with a set of four resistance mechanisms  103  being shown in the embodiment of  FIGS.  1 - 12   . As shown, the pedal  101  includes a toe end portion  104  and a heel end portion  105 , and the pedal  101  is pivotably connected to the base  102  substantially midway between the toe end portion  104  and the heel end portion  105  of pedal  101 , as will be described in further detail below. As illustrated best perhaps in  FIGS.  6  and  7   , the base  102  provides a bottom surface  140  configured to support the device  100  against a support surface (e.g., the floor, ground, or a vertical support board  160 ) and configured to resist movement of device  100  relative to the support surface  160  while a user  123  is using the device  100 . The pedal  101  provides a foot surface  150  configured to receive and support a foot  121  of the user  123  while the user  123  is using the device  100 , as will be described in more detail below. 
     The pedal  101  may be formed from any material suitable for receiving and supporting the foot of a user in accordance with the present disclosure. In various exemplary embodiments, the pedal  101  may, for example, comprise a molded plastic material, such as, for example, a molded polypropylene material. Those of ordinary skill in the art will understand, however, that the pedal  101  may be made of various plastic materials, as well as various other materials, including, for example, wood and/or metal materials, as described further below. Suitable materials can include, for example, materials that are relatively light to facilitate carrying, packing, and transporting the device  100 , yet durable and able to withstand repetitive use/motion. 
     As illustrated in  FIGS.  1 - 12   , the pedal  101  can be shaped to receive a user&#39;s foot, for example, the foot  121  of the user  123  (see  FIGS.  6  and  7   ). In one exemplary embodiment, for example, the pedal  101  comprises a substantially flat, rectangular body  107  configured to receive the foot  121  of the user  123 . In other exemplary embodiments, as illustrated in the embodiments of  FIGS.  22 - 27   , the pedal may comprise a more contoured shape that loosely resembles the shape of a foot. The pedal  101  can be sized to accommodate a range of foot and/or shoe sizes. In various exemplary embodiments of the present disclosure, for example, the pedal  101  can have a length L P  (see  FIG.  3   ) ranging from about 8 inches to about 15 inches, for example from about 9 inches to about 10 inches, and a width WP (see  FIG.  4   ) ranging from about 2 inches to about 7 inches, for example, about 4 inches to about 5 inches. 
     As discussed above, the pedal  101  includes a toe end portion  104 , a heel end portion  105 , and a foot surface  150  extending between the toe end portion  104  and the heel end portion  105 . The foot surface  150  may include, for example, various ridges, treads (see, e.g., foot surface  550  of portable exercise device  500  of  FIGS.  18 - 21   ), coatings, applied surfaces (e.g., grip tape), laser markings, and/or other mechanisms to increase user comfort and/or to increase friction on the foot surface  150  with which the foot comes into contact, for example, to massage the user&#39;s foot and/or prevent the foot from slipping on the foot surface  150 . Massage of the user&#39;s foot, via the foot surface  150  and any elements, coatings, or surfaces applied thereto, will apply pressure to the sole of the foot during the exercise, i.e., plantar pressure, which also contributes to movement of fluid through the body tissue and to an increase in circulation of bodily fluids. 
     In various embodiments, the foot surface  150  may include a removable pad upon which the foot may rest for comfort and/or additional support. Additionally or alternatively, the pad may be made from a soft, form fitting material, such as, for example, a shape memory polymer, which may conform to the feet of different users, as would be understood by those of ordinary skill in the art. In various additional embodiments, to simplify the device  100 , grip tape and/or laser markings may be applied directly to the foot surface  150 . 
     The pedal  101 , and the foot surface  150  of the pedal  101 , may have various sizes (i.e., dimensions), shapes, configurations and/or features without departing from the scope of the present disclosure. In various embodiments, for example, a foot guide can be placed on the foot surface  150  to assist in the proper placement of a user&#39;s foot on the pedal  101 . The foot guide may include, for example, a movable guide and/or a printed outline that is representative of several general foot size categories. In various further embodiments, the pedal may also be extensible to accommodate various foot/shoe sizes. For example, the pedal may be extensible such that both ends of the pedal are configured to move away from a center of the pedal a corresponding distance, to maintain a central position of the pivot axis and maintain stability of the device. 
     The base  102  may be formed from any material and/or combination of materials suitable for mounting the pedal  101  and stably supporting the device  100  relative to the support surface  160  while the user is using the device  100  in accordance with the present disclosure. In various exemplary embodiments, the base  102  may, for example, comprise a molded plastic material, such as, for example, a molded polypropylene material. Those of ordinary skill in the art will understand, however, that the base  102  may be made of various plastic materials, as well as various other materials, including, for example, wood and/or metal materials, as described further below. Suitable materials can include, for example, materials that are relatively light to facilitate carrying, packing, and transporting the device  100 , yet durable and able to withstand repetitive use. 
     As shown in  FIGS.  1 - 12   , in one exemplary embodiment of the present disclosure, the base  102  comprises a substantially flat, rectangular body  107  provided with a bottom surface  140  that is configured to rest against a support surface  160 , while the user  123  is using the device  100  (see  FIGS.  6  and  7   ). The base  102  is appropriately sized and/or configured to stably support the pedal  101  (e.g., against the support surface  160 ), when the exercise device  100  is in use. The body  106  of the pedal  101  and the body  107  of the base  102  have similar dimensions such that, when the device  100  is in the open configuration, and the pedal  101  is positioned to receive the foot  121  of the user  123  (see  FIGS.  6  and  7   ), the pedal  101  is substantially parallel to the base  102  and respective corners of the bodies  106  and  107  are substantially in alignment with each other. Thus, in various exemplary embodiments, like the pedal  101 , the base  102  can have a length L B  (see  FIG.  3   ) ranging from about 8 inches to about 15 inches, for example from about 9 inches to about 10 inches, and a width W B  (see  FIG.  4   ) ranging from about 2 inches to about 7 inches, for example, about 4 inches to about 5 inches. 
     The base  102  may take on a variety of sizes, shapes, configurations and/or features without departing from the scope of the present disclosure. As illustrated in  FIGS.  1 - 21   , in some embodiments, for example, the base is solid, while in other embodiments, the base has cutouts (see, e.g.,  FIGS.  22 - 27   ) configured to reduce the weight of the base. Furthermore, in some embodiments, the bottom surface  140  of the base  102  may include various ridges, treads, coatings, applied surfaces, and/or other mechanisms to increase friction between the bottom surface  140  and the support surface  160  upon which the base  102  rests to prevent slippage of the base  102  on the support surface  160 . In other embodiments, the base  102  may be configured to be secured to the support surface  160 , via, for example, a bolt, screw, hook and loop material, and/or clamp. 
     In accordance with various embodiments, for example, to accommodate users in various positions, the device  100  may be used in both a sitting position (see  FIG.  6   ) and a supine position (see  FIG.  7   ). For example, as will be understood by those of ordinary skill in the art, the positioning of the device  100  can be adjusted such that the foot support portion  101  is disposed in a first position wherein the pedal  101  is in a neutral position N to receive a foot  121  of a user  123  in a sitting position (see  FIG.  6   ) and a second position wherein the pedal  101  is in the neutral position N to receive a foot  121  of a user  123  in a supine position (see  FIG.  7   ). In one example, to better support use in the supine position, the bottom surface  140  of the base  102  may be secured to a vertical support surface  160 , such as, for example, a back-board  160  of a bed surface  170 , as illustrated in  FIG.  7   . 
     As illustrated in  FIGS.  6  and  7   , in such embodiments (e.g., wherein the device  100  is secured to the support surface  160 ), the device  100  may further comprise at least one strap  130  affixed to the pedal  101 , two straps  130  (i.e., a toe strap and a heel strap) being shown in the embodiment of  FIGS.  6  and  7   . The straps  130  may, for example, be configured to releasably secure the foot  121  of the user  123  to the pedal  101 . The straps  130  can be adjustable to permit loosening and tightening of the straps  130  around a user&#39;s foot. By way of example only, the straps  130  may comprise hook and loop fasteners, such as, for example, Velcro®. Those of ordinary skill in the art will further understand that the straps  130  may comprise any type and/or configuration or mechanism to releasably secure a foot of the user to the pedal  101 , including for example, snaps, buttons, ties, buckles, elastic bands and/or any combination thereof. As will also be understood by those of ordinary skill in the art, the presence of a strap or other securing means is optional and is not necessary for use of the device. In some embodiments, for the device to be functional while secured to a user&#39;s foot, the base of the device must be secured to the floor, ground, or other stable surface. Thus, in some embodiments and in certain environments, operation of the device without a securing means may be preferred. 
     In accordance with exemplary embodiments of the present disclosure, the pedal  101  is pivotably connected to the base  102  via at least one hinge. As illustrated best perhaps in the open configuration of  FIGS.  1 - 7   , in one exemplary embodiment, the pedal  101  is pivotably mounted to the base  102  via a double-hinged support. For example, as shown in  FIGS.  1 - 7   , a support  110  is positioned between a first hinge  109  and a second hinge  111 , wherein the first hinge  109  is connected to the pedal  101  and the second hinge  111  is connected to the base  102 . As shown, the support  110  may be connected to the pedal  101 , via the hinge  109 , substantially midway between the toe end portion  104  and the heel end portion  105  of the body  106  of pedal  101 . The support  110  may also be mounted to the base  102 , via the hinge  111 , substantially midway between corresponding end portions of the body  107  of base  102 . In this manner, the support  110  is configured to rotate, via the hinges  109  and  111 , between an upright position (see  FIGS.  1 - 7   ) and a collapsed position (see  FIGS.  8 - 12   ), as will be explained further below. When the support  110  is positioned in the upright position, as illustrated in  FIGS.  1 - 7   , the support  110  extends between and substantially perpendicular to the parallel bodies  106  and  107  of the pedal  101  and the base  102 , respectively, thereby creating a space S therebetween (see  FIG.  3   ). In such a configuration, the pedal  101  can pivot, via the hinge  109 , toward and away from the base  102 , and can have a neutral position N relative to a pivot axis P (see  FIG.  14   ). 
     As used herein, the term “neutral position” refers to a pedal starting position and a position of the pedal without external forces acting thereon to pivot the pedal about the pivot axis P (e.g., about the hinge  109 ). Thus, when a pedal is in the “neutral position,” the foot of a user, which is received by the pedal, is in a relaxed, un-flexed position (i.e., the user&#39;s foot is neither extended or flexed). In the exemplary embodiment of  FIGS.  1 - 7   , in the “neutral position”, the pedal  101  is substantially parallel to the base  102 . With reference to  FIGS.  13 A,  13 B, and  14   , the pedal  101  is configured to rotate about the pivot axis P in a first direction away from the neutral position N and toward the base  102  and in a second direction away from the neutral position N and toward the base  102 , wherein the second direction is opposite the first direction. For example, the pedal  101  is configured to undergo a rocking type motion in which the pedal  101  rotates about the pivot axis P in a first direction F away from the neutral position N (see  FIG.  13 A ) in which the toe end portion  104  moves toward the base  102  (and the heel end portion  105  moves away from the base  102 ) and in a second direction E (see  FIG.  13 B ) away from the neutral position N in which the heel end portion  105  moves toward the base  102  (and the toe end portion  104  moves away from the base  102 ). In this manner, rotation is around the axis P provided by the hinge  109  on the device  100 , and, as illustrated in  FIG.  14   , the user&#39;s ankle  141  must pivot around this axis in an arc C. Consequently, the user&#39;s leg  122  must also move, in both an arc B and an arc C, to accommodate the rotation of the ankle  141  about the pivot P. For example, when the user  123  performs a plantarflexion motion, the ankle  141  rises, so the leg  122  must also rise. Similarly, when the user  123  performs a dorsiflexion motion, the ankle  141  lowers, so the leg  122  must also move lower. 
     The support  110  extending between the pedal  101  and the base  102  has a height h. When the device  100  is in the open, in use configuration, the pedal  101  and the base  102  are spaced apart from one another by the height h of the support  110 . This space S has a height H S1  when the device  100  is in the open configuration (see  FIG.  3   ). The respective heights of the support  110  and the space S are configured to allow sufficient rotation of the pedal  101  in the first direction F about the pivot axis P (see  FIG.  14   ) to subject a foot  121  of a user  123  to full flexion and to allow sufficient rotation of the pedal  101  in the second direction E about the pivot axis P (see  FIG.  14   ) to subject the foot  121  of the user  123  to full extension. In various embodiments, for example, the space S may have a height H S1  that is sufficient for the length of the pedal  101  to clear the base  102  when moved through 75 degrees of plantar flexion and 60 degrees of dorsiflexion. Those of ordinary skill in the art will understand that, to support the pedal  101  while also achieving the goal of full ankle flexion/extension, the support  110  may employ various pivoting mechanisms, and have various shapes, configurations and/or sizes (i.e., dimensions), including various heights h, which create various spaces S (i.e., having various heights H S1 ) between the pedal  101  and the base  102 , without departing from the scope of the present disclosure. 
     The resistance mechanism  103  is configured to exert a force on the pedal  101  about the pivot axis P in a direction opposite to a respective direction of rotation of the pedal  101  about the pivot axis P. In one exemplary embodiment, the resistance mechanism  103  comprises a plurality of elastomeric bands  103 , each of the bands  103  extending between and connected to the pedal  101  and the base  102 . For example, as illustrated in  FIGS.  1 - 12   , an elastomeric band  103  extends between each pair of aligned corners of the bodies  106  and  107  of the pedal  101  and the base  102 . During rotation of the pedal  101 , the elastomeric bands  103  exert a force on the pedal  101  about the pivot axis P in a direction opposite to the respective direction of rotation of the pedal  101  about the pivot axis P. For example, when a foot presses down on the toe end portion  104  or the heel end portion  105  of the pedal  101 , the elastomeric bands  103  on the opposite side of the device  100  (i.e., opposite to the pressing action) extend, thereby exerting a force against the movement of the pedal  101 . In other words, when a foot (e.g., toes of the foot) presses down on the toe end portion  104 , thereby moving the toe end portion  104  of the pedal  101  toward the base  102 , the elastomeric bands  103  connected to the heel end portion  105  are extended as the heel end portion  105  moves away from the base  102 , thereby exerting a force that resists the movement of the heel end portion  105  away from the base and the toe end portion  104  toward the base. Likewise, when a foot (e.g., a heel of the foot) presses down on the heel end portion  105 , thereby moving the heel end portion  105  of the pedal  101  toward the base  102 , the elastomeric bands  103  connected to the toe end portion  104  are extended as the toe end portion  104  moves away from the base  102 , thereby exerting a force that resists the movement of the toe end portion  104  away from the base and the heel end portion  105  toward the base. 
     Accordingly, in various exemplary embodiments of the present disclosure, the force exerted by the elastomeric bands  103  may provide passive resistance to rotational movement of the pedal  101  in both directions (i.e., F and E of  FIG.  14   ) about the pivot axis P. And, in various additional embodiments, an amount of the force may vary with a degree of rotation θ (see  FIG.  14   ) of the pedal  101  about the pivot axis P, for example, the amount of force may increase with the degree of rotation θ of the pedal  101  about the pivot axis P. 
     Furthermore, to change the amount of force or resistance exerted by the elastomeric bands  103 , various additional embodiments of the present disclosure contemplate, for example, providing elastomeric bands  103  that are removable and/or reconfigurable, such that additional elastomeric bands  103  may be added to the device  100 , in addition to and/or in exchange for existing elastomeric bands  103 . In this manner, a user of the device  100  may increase and/or decrease the amount of force that is exerted by the elastomeric bands, to, for example, accommodate a user as strength increases or to otherwise scale up and/or down an exercise routine. 
     Those of ordinary skill in the art will understand that resistance mechanisms in accordance with the present disclosure may comprise various types, numbers, configurations, and/or combinations of elements that may exert a force on the pedal  101  about the pivot axis P in a direction opposite to the respective direction of rotation of the pedal  101  and are not limited in any way to elastomeric bands, or to the particular exemplary configuration of elastomeric bands  103  of the embodiment illustrated in  FIGS.  1 - 12   . Examples of resistance mechanisms other than elastomeric bands that can be used, or that can be used in combination with elastomeric bands, for example, at each respective end portion of the pedal  101 , include but are not limited to, for example, springs (see, e.g., springs  203  in portable exercise device  200  of  FIG.  15   ), inflatable devices (see, e.g., inflatable bags  303  in portable exercise device  300  of  FIG.  16   ), bellows (see, e.g., bellows  403  in portable exercise device  400  of  FIG.  17   ), and/or foams. 
     When such non-elastomeric resistance mechanisms are utilized (e.g., springs  203 , inflatable bags  303 , and/or bellows  403 ), the resistance mechanisms on the same side of the device  100  as the pressing action may assist in returning the pedal  101  to the neutral position. In other words, when the toe end portion  104  of the pedal  101  moves toward the base  102 , the non-elastomeric resistance mechanisms connected to the toe end portion  104  may assist in returning the pedal  101  to the neutral position N; and when the heel end portion  105  of the pedal moves toward the base  102 , the non-elastomeric resistance mechanisms connected to the heel end portion  105  may assist in returning the pedal  101  to the neutral position N. In various exemplary embodiments, the amount of assist respectively provided by the non-elastomeric resistance mechanisms on the pedal  101  is proportional to the amount by which the pedal  101  is rotated about the pivot axis P and away from the neutral position N. 
     Various additional exemplary embodiments further contemplate utilizing a resistance mechanism that is positioned at the pivot P, as disclosed, for example, in U.S. Provisional Application No. 62/635,165, entitled “Devices and Methods for Exercising an Ankle, Foot, and/or Leg” and filed on Feb. 26, 2018, the entire contents of which are incorporated by reference herein. Such resistance mechanisms may include, for example, but are not limited to friction devices, torsion bars, spring devices (e.g., torsion springs/linear springs), detent dials, adjustable clutch mechanisms, piezoelectric/nanomotion motors, pneumatic, and/or hydraulic devices, such as, for example, hydraulic cylinders (see below), viscous damping devices, and/or devices utilizing smart fluids, such as, for example, magnetorheological fluids or electrorheological fluids. As illustrated in  FIG.  22   , for example, various exemplary embodiments of the present disclosure contemplate a portable exercise device  600 , which includes molded hinges  609  (not shown in the view of  FIGS.  22   ) and  611  that are integral with a collapsible support  610 . The collapsible support  610  may, for example, be made from a molded plastic material with the hinges  609  and  611  and/or locking mechanisms molded into it. In such a configuration, the molded hinge  609  could also house an adjustable resistance mechanism, such as, for example, one of the resistance mechanisms disclosed in U.S. Provisional Application No. 62/635,165. The resistance mechanisms and the respective ranges of resistance for the resistance mechanisms disclosed in U.S. Provisional Application No. 62/635,165 are incorporated herein by reference. 
     For portability, the device  100  is adjustable between at least two configurations. As shown in  FIGS.  1 - 7   , the device  100  may be adjusted to an open configuration wherein the pedal  101  is disposed in the neutral position N to receive a foot  121  of a user  123 . Alternatively, as shown in  FIGS.  8 - 12   , the device  100  may be adjusted to a closed configuration wherein the pedal  101  is collapsed against the base  102  to minimize the space S between the pedal  101  and the base  102 , thereby minimizing the profile of the device  100  for ease of transport. Thus, as discussed above, the device  100  includes a collapsible support  110  that is configured to rotate, via hinges  109  and  111 , between an upright position in which the support  110  is perpendicular to the parallel bodies  106 ,  107  of the pedal  101  and the base  102  (see  FIGS.  1 - 7   ) and a collapsed position in which the support  110  is parallel to the parallel bodies  106 ,  107  of the pedal  101  and the base  102  (see  FIGS.  8 - 12   ). In this manner, the device  100  may be transitioned between the open and closed configuration via moving the support  110  between the upright and collapsed position, for example, by raising and lowering the support  110  with respect to the base  102  via the hinges  109  and  111 . 
     Those of ordinary skill in the art will understand that embodiments of the present disclosure contemplate various mechanisms, which include various configurations of features, for transitioning the device  100  between the open and closed configurations, and are not limited in any way to the collapsible support  110  of the embodiment illustrated in  FIGS.  1 - 12   . Furthermore, the collapsible support  110  may be used in combination with various mechanisms to increase the stability of the device  100 , when the device is in the open configuration. In various embodiments, for example, as illustrated in the embodiment of  FIGS.  18 - 21   , the device may further include a block that is secured to the base, against which the collapsible support may rest when in the open configuration. 
     In accordance with various embodiments of the present disclosure, the device  100  may include, for example, a closure mechanism  115  that is configured to transition the device  100  between the open and closed configurations. In various exemplary embodiments, the closure mechanism  115  includes a cord  116  and a clamp  117 , such as, for example, a v-clamp  117 . As illustrated in the embodiment of  FIGS.  1 - 12   , the clamp  117  is mounted to an end portion of the base  102 , on a top surface  145  of the base  102 . And, the cord  116  is configured to extend between the support  110  and the clamp  117 . In various exemplary embodiments, the cord  116  is affixed to the support  110  at a location adjacent to the pedal  101 , such as, for example, at a location of the hinge  109  connecting the support  110  to the pedal  101 . As shown best perhaps in  FIGS.  3 - 5   , a first end of the cord  116  may be, for example, threaded through a hole  119  in the hinge  109 /support  110  and knotted on the opposite side of the support  110 , while a second end of the cord  116  is threaded through the clamp  117 . In this manner, the support  110  may be raised and lowered with respect to the base  102  (i.e., transitioned between the upright and collapsed configurations) by respectively securing and releasing the cord  116  within the clamp  117 . In other words, to raise the support  110  and maintain (lock) the support  110  in the upright configuration, the cord  116  may be pulled taut and secured within the clamp  117 . And, to lower the support  110  the cord  116  may be released from the clamp  117 , such that the cord  116  is slackened to allow the support  110  to collapse against the top surface  145  of the base  102  via the hinges  109  and  111 . 
     Those of ordinary skill in the art will understand that devices in accordance with the present disclosure may comprise various types, numbers, configurations, and/or combinations of closure mechanisms to transition the device between the open configuration and the closed configuration and are not limited in any way to the cord and clamp mechanism of the embodiment illustrated in  FIGS.  1 - 12   . As illustrated in the embodiment of  FIG.  22   , for example, one embodiment of the present disclosure contemplates a device  600  that utilizes a plastic clamp  617  to lock the device  600  in the open configuration. The clamp  617  may include, for example, an upper jaw  618  that pivots with respect to a lower jaw  619 , such that the upper jaw  618  may clamp down on a cord  616  that runs between the jaws  618  and  619 . As illustrated in the embodiment of  FIGS.  13 A and  13 B , for example, various additional embodiments of the present disclosure contemplate that the device  100  utilizes a cord  116  that interconnects directly with the base  102 , such as, for example, with a notch  114  or other feature of the base  102 . In various additional embodiments, the device may utilize a cord that has a ball at one end (see e.g., cord  516 , having a ball  560 , of portable exercise device  500  of  FIGS.  18 - 21   ) to prevent the cord from sliding through the clamp. In various further exemplary embodiments, the device  100  may utilize a bar that is raised and lowered with respect to the support  110  to lock the support in the open configuration (e.g., similar to a kick stand as illustrated in the exemplary embodiment of  FIGS.  34  and  35   ). 
     As illustrated in  FIGS.  8 - 12   , in the closed configuration of the device  100 , the pedal  101  is collapsed against the base  102 , reducing the space S between the pedal  101  and the base  102 , such that the device  100  has a minimized profile. In this configuration, the support  110  is in a collapsed position in which the support  110  is parallel to the parallel bodies  106 ,  107  of the pedal  101  and the base  102 . In other words, in the closed configuration of the device  100 , the cord  116  of the closure mechanism  115  is slack such that the pedal  101  and support  110  can pivot, via the hinges  109  and  111 , to collapse and lay flat against the base  102 . Consequently, in this configuration, the elastomeric bands  103  are also substantially slack and collapsed with respect to the base  102 , as further illustrated in  FIGS.  8 - 12   . 
     In accordance with various exemplary embodiments, in the closed configuration of the device  100 , the space S between the pedal  101  and the base  102  is minimized such that a height H S2  of the space S is less than the height H S1  of the space S when the device  100  is in the open configuration. Consequently, in the closed configuration of the device  100 , an overall height of the device  100  is also reduced. In various embodiments, for example, an overall height H 1  of the device  100  in the open configuration (see  FIG.  3   ) ranges from about 3 inches to about 5 inches, while an overall height H 2  (see  FIG.  10   ) of the device in the closed configuration ranges from about 1 inches to about 3 inches. 
     To help keep the device in the closed configuration, various embodiments of the present disclosure may also include a restraint. One exemplary embodiment may include a tie mechanism, such as, for example, a band (see, e.g., band  580  of portable exercise device  500  of  FIG.  21   ) that is tied around the device to secure the collapsed pedal to the base. Another exemplary embodiment may include a pair of components configured to fit together in a tight manner such as in a press-fit or snap fit manner (see, e.g., components  980  and  981  of portable exercise device  900  of  FIGS.  25  and  26   ) and that lock together when the device is in the closed configuration to secure the collapsed pedal to the base (see  FIG.  26   ). In the exemplary embodiment, the elements comprise projection  981  and hole  980  that fit together in a press-fit or snap-fit manner. However, as will be apparent to those of ordinary skill in the art, it is possible that other configurations of objects to be connected in a press-fit or snap-fit manner may be used. For example, nesting objects which fit together in a press-fit or snap-fit manner may be used. Another exemplary embodiment may include a strap, such as, for example, a Velcro® strap that is connected to the pedal and configured to attach, for example, to a loop material on a bottom surface of the base (see, e.g., strap  1080  and material  1081  of portable exercise device  1000  of  FIGS.  28  and  29   ) when the pedal is collapsed against the base (see  FIG.  29   ). Another exemplary embodiment may include a magnet on a top surface of the base (see, e.g., magnet  1181  of portable exercise device  1100  of  FIGS.  30  and  31   ) that is configured to attach to a corresponding magnet on a bottom surface of the pedal (not shown in the view of  FIG.  30   ) when the pedal is collapsed against the base (see  FIG.  31   ). Those of ordinary skill in the art will understand that devices in accordance with the present disclosure may comprise various types, numbers, configurations, and/or combinations of restraint mechanisms to help keep the device in the closed configuration and are not limited in any way to the components illustrated in  FIGS.  21 ,  25 ,  26 , and  28 - 31   . Those of ordinary skill in the art will further understand that devices in accordance with the present disclosure may be used in conjunction with various accessory devices, for example, in which to store the device when the device is locked in the closed configuration. As illustrated in  FIG.  27   , for example, various embodiments of the present disclosure contemplate portable exercise devices that, when locked in the closed configuration, are stored within a sleeve, such as, for example, a cloth or neoprene sleeve (see, e.g., sleeve  1200  of  FIG.  27   ). A storage sleeve may, for example, provide both function and aesthetics. The sleeve may (1) protect the device from damage, (2) contain dirt and other contaminants the device may pick up during use, (3) aid in the carrying of the device, and (4) provide an aesthetic means of transporting and storing the device. 
     Various additional embodiments of the present disclosure contemplate utilizing a single locking mechanism that functions to both (1) lock the device in the open configuration for use, and (2) lock the device in the closed configuration for storage. In one embodiment, such a locking mechanism may function, for example, similar to the conventional locking mechanism utilized by folding tables, in which the support includes a sliding arm that is spring-loaded on a pin. As will be understood by those of ordinary skill in the art, as the sliding arm gets pushed out (i.e., to open the device) and in (i.e., to close the device), the arm may slide back and forth along the pin (i.e., via a slot/track in the center of the arm). And, at either end of the track (i.e., when the device is fully open or fully closed), the arm pops out of the track and locks into place. To change the configuration of the device, the user then depresses the pin to unlock the device and move the pin back into the track. In accordance with various additional exemplary embodiments, as illustrated in  FIGS.  34  and  35   , an exercise device  1400  may include a similar locking mechanism comprising an arm  1417  that is configured to lock into place, in either an open configuration (see  FIG.  34   ) or a closed configuration (see  FIG.  35   ), for example, via notches  1418  in the base  1402  of the device  1400 . In this manner, the arm  1417  functions like a kick stand that may lock into place in either an open or closed configuration. In still further exemplary embodiments, as illustrated in  FIGS.  36 - 42    and described below, exercise devices  1500  and  1600  may each include a locking mechanism  1515 ,  1615  comprising a strap (e.g., a soft goods strap)  1516 ,  1616  that is used in conjunction with a hook (e.g., a G-hook)  1517 ,  1617  to lock the device  1500 ,  1600  into place, in either an open configuration (see  FIGS.  36  and  40   ) or a closed configuration (see  FIGS.  37 - 39    and  FIGS.  41 - 42   ). 
     As described above, those of ordinary skill in the art will understand that the disclosed portable exercise devices, including the pedal and support, may be made of various materials, including, for example, various light weight wood materials, such as, for example, plywood, medium-density fiberboard (MDF), birch wood, and balsam wood. As above, such materials may be relatively light to facilitate carrying, packing, and transporting the device, yet durable enough to withstand repetitive use/motion.  FIGS.  23 - 31  and  36 - 42   , for example, illustrate several exemplary embodiments of portable exercises devices  700 ,  800 ,  900 ,  1000 ,  1100 ,  1500 , and  1600  made from a light weight wood material. 
     Similar to the portable exercise device  100  described above, each of the devices  700 ,  800 ,  900 ,  1000 , and  1100  includes a pedal  701 ,  801 ,  901 ,  1001 ,  1101 ; a base  702 ,  802 ,  902 ,  1002 ,  1102 ; and a collapsible support  710 ,  810 ,  910 ,  1010 ,  1110  connecting the pedal  701 ,  801 ,  901 ,  1001 ,  1101  to the base  702 ,  802 ,  902 ,  1002 ,  1102  (e.g., via hinges); such that the pedal  701 ,  801 ,  901 ,  1001 ,  1101  may be raised and lowered with respect to the base  702 ,  802 ,  902 ,  1002 ,  1102 . Also similar to the portable exercise device  100 , each of the devices  1500  and  1600  includes a pedal  1501 ,  1601  and a base  1502 ,  1602 . In the exemplary embodiments of  FIGS.  36 - 42   , however, each base  1502 ,  1602  comprises of a pair of collapsible supports  1510   a ,  1610   a  and  1510   b ,  1610   b  that are connected to the pedal  1501 ,  1601  via a hinge  1509 ,  1609 . In this manner, when the device  1500 ,  1600  is in the open configuration (see  FIGS.  36  and  40   ), the supports  1510   a ,  1610   a  and  1510   b ,  1610  of the base  1502 ,  1602  form a triangular body that elevates the pedal  1501 ,  1601  with respect to the support surface. And, when the device  1500 ,  1600  is in the closed configuration (see  FIGS.  37 - 39    and  FIGS.  41 - 42   ), the supports  1510   a ,  1610   a  and  1510   b ,  1610  of the base  1502 ,  1602  fold (via the hinge  1509 ,  1609 ) flat against the pedal  1501 ,  1601 . 
     To both simplify and reduce the weight of the devices  700 ,  800 ,  900 ,  1000 ,  1100 ,  1500 ,  1600  in the present embodiments, these components are at least partly made from a wood material. In one embodiment, for example, the pedals  701 ,  801 ,  901 ,  1001 ,  1101  bases  702 ,  802 ,  902 ,  1002 ,  1102  and supports  710 ,  810 ,  910 ,  1010 ,  1110  are each made of plywood, such as, for example, a ¼ inch to a ⅜ inch plywood that is sanded and varnished to a smooth finish. In another embodiment, the pedal  1501  and the supports  1510   a  and  1510   b  are each made of MDF, with the pedal further including a birch top piece  1550 . In yet another embodiment, the pedal  1601  is made of MDF with a birch top piece  1650 , while the supports  1610   a  and  1610   b  are made of aluminum. In various embodiments, for example, the supports  1610   a  and  1610   b  include bent, hollow tubes. Furthermore, as illustrated in  FIG.  38   , in such embodiments, elastomeric bands  1503 ,  1603  of the resistance mechanism may be passed through an MDF support  1547 ,  1647  of the pedal  1501 ,  1601 , which is covered by the birch top piece  1550 ,  1650 , and connected to respective supports  1510   a ,  1610   a  and  1510   b ,  1610   b  (e.g., via holes  1513 ,  1613  (see, e.g.,  FIGS.  36  and  40   ) in the supports  1510   a ,  1610   a  and  1510   b ,  1610   b ). Those of ordinary skill in the art will understand that the wood embodiments depicted in  FIGS.  23 - 31  and  36 - 42    are exemplary only and that any combination of wood/non-wood materials may be used. 
     Those of ordinary skill in the art will further understand that various resistance mechanisms and locking mechanisms, as described above in  FIGS.  1 - 22   , may be used in conjunction with such wood devises. As illustrated in  FIG.  23   , for example, in one exemplary embodiment, similar to the embodiment of  FIG.  22   , the device  700  utilizes a locking mechanism comprising a plastic clamp  717 . As illustrated in  FIG.  33   , in another exemplary embodiment, a device  1300  utilizes a locking mechanism comprising a plastic cleat  1317  that is embedded within a keyhole  1318  cut into a base  1302  of the device  1300 . As will be understood by those of ordinary skill in the art, in such embodiments, to lock the device  1300  in the open configuration, the pedal may be raised and a cord  1316  may be locked within teeth  1312  of the cleat  1317 . In other exemplary embodiments, similar to the embodiment of  FIGS.  13 A and  13 B , the devices  800 ,  900 ,  1000 ,  1100  respectively utilize a cord  816 ,  916 ,  1016 ,  1116  that interconnects directly with the base  802 ,  902 ,  1002 ,  1102  such as, for example, with holes  812 ,  912 ,  1012 ,  1112  and  814 ,  914 ,  1014 ,  1114  or other features of the base  802 ,  902 ,  1002 ,  1102 . For example, the device  800 ,  900 ,  1000 ,  1100  may have two differently sized holes  812 ,  912 ,  1012 ,  1112  and  814 ,  914 ,  1014 ,  1114  that are connected by a small channel  815  (not shown),  915  (see  FIG.  26   ),  1015  (see  FIG.  29   ),  1115  (see  FIG.  31   ). The smaller of the two holes  812 ,  912 ,  1012 ,  1112  is configured to retain a small knot  813 ,  913 ,  1013 ,  1113  in the cord  816 ,  916 ,  1016 ,  1116  to lock the device  800 ,  900 ,  1000 ,  1100  in the open configuration (see  FIGS.  24 ,  25 ,  28 , and  30   ) and the larger of the two holes  814 ,  914 ,  1014 ,  1114  is configured to let the knot  813 ,  913 ,  1013 ,  1113  pass. In this manner, the device  800 ,  900 ,  1000 ,  1100  may be closed by tugging the cord  816 ,  916 ,  1016 ,  1116  through the channel  815 ,  915 ,  1015 ,  1115  to move the cord from the small hole  812 ,  912 ,  1012 ,  1112  to the large hole  814 ,  914 ,  1014 ,  1114 . In still further exemplary embodiments, the devices  1500 ,  1600  utilize a locking mechanism  1515 ,  1615  that includes a strap (e.g., a soft goods strap)  1516 ,  1616  (including two strap portions) and a hook (e.g., a G-hook)  1517 ,  1617 . The strap  1515 ,  1615  connects directly to each of the supports  1510   a ,  1610   a  and  1510   b ,  1610   b  and is adjusted (i.e., to lock the device  1500 ,  1600  in either the open or closed configuration) via the hook  1517 ,  1617 . In the embodiment of  FIGS.  36 - 39   , for example, a respective strap portion  1516   a  and  1516   b  is connected to each support  1510   a  and  1510   b  via a notch  1512  in the base of each support  1510   a  and  1510   b . And, in the embodiment of  FIGS.  40 - 42   , a respective strap portion  1616   a  and  1616   b  is configured to wrap around the base of each support  1610   a  and  1610   b  (i.e., around an aluminum tube forming the base of each support  1610   a  and  1610   b ). Thus, as illustrated in  FIGS.  36  and  40   , when the device  1500 ,  1600  is in the open configuration, the two strap portions  1516   a ,  1616   a  and  1516   b ,  1616   b  are connected via the hook  1517 ,  1617  such that the strap  1516 ,  1616  runs under the triangular body formed by the supports  1510   a ,  1610   a  and  1510   b ,  1610   b . And, as illustrated in  FIGS.  37  and  41   , when the device  1500 ,  1600  is in the closed configuration, the two strap portions  1516   a ,  1616   a  and  1516   b ,  1616   b  are connected via the hook  1517 ,  1617  such that the strap  1516 ,  1616  runs over the birch top piece  1550 ,  1650 . 
     As above, for portability it is also advantageous for devices in accordance with the present disclosure (including the wood devices) to have a low profile when in the closed configuration (i.e., to minimize the packing profile). Accordingly, as illustrated in the embodiments of  FIGS.  25 - 31   , various embodiments further contemplate utilizing components that lock together when the device is in the closed configuration. One embodiment, for example, contemplates utilizing a pair of components  980  and  981  that fit together in a tight manner (e.g., a press-fit or snap fit manner) when the device  900  is in the closed configuration. The components may, for example, include a rubber piece  981  on the support  910  that is configured to imbed within a hole  980  in the pedal  901  when the device  900  is in the closed configuration. Another embodiment contemplates utilizing components  1080  and  1081  that stick together when the device  1000  is in the closed configuration. The components may, for example, include a “hook-type” fastener material  1080  on the pedal  1001  (e.g., a Velcro® strip) that is configured to attach to a “loop-type” fastener material  1081  on the support  1002  (e.g., on the bottom surface of the support  1002 ) when the device  1000  is in the closed configuration. Another embodiment contemplates utilizing components that connect magnetically when the device  1100  is in the closed configuration. The components may, for example, include a magnet  1181  on a top surface of the support  1102  that is configured to connect to a magnet (not shown) on a bottom surface of the pedal  1101  when the device  1100  is in the closed configuration. 
     As illustrated in the embodiments of  FIGS.  36 - 42   , various additional embodiments contemplate utilizing a pedal  1501 ,  1601  and base  1502 ,  1602  that are configured to lay flush when the device  1500 ,  1600  is in the closed configuration. In the embodiment of  FIGS.  36 - 39   , for example, to place the device  1500  into the closed configuration, the wood supports  1510   a  and  1510   b  may rotate (via the hinge  1509 ) up against the pedal  1501  (i.e., such that they lay flat against an underside of the support  1547  of the pedal  1501 ), and the elastomeric bands  1503  are configured to nest internally within the support  1547  of the pedal  1501  (not shown). Similarly, in the embodiment of  FIGS.  40 - 42   , to place the device  1600  into the closed configuration, the aluminum supports  1610   a  and  1610   b  may rotate (via the hinge  1609 ) up against the pedal  1601  (i.e., such that they frame the support  1647  and lay flat against an underside of the top piece  1650  of the pedal  1601 ); and the elastomeric bands  1603  are configured to nest within cutouts  1614  in an underside of the support  1647  of the pedal  1601  (see  FIG.  42   ). 
     Such components and configurations may serve to minimize the packing profile of the device  900 ,  1000 ,  1100 ,  1500 ,  1600  while also helping to secure the pedal  901 ,  1001 ,  1101 ,  1501 ,  1601  to the base  902 ,  1002 ,  1102 ,  1502 ,  1602  during transport. Also, as above, to provide both protection and containment (e.g., of any dirt or contaminants that the device  900 ,  1000 ,  1100 ,  1501 ,  1601  may have picked up during use), the device  900 ,  1000 ,  1100 ,  1501 ,  1601  may also be inserted into a storage sleeve  1200  as illustrated, for example, in  FIG.  27   . 
     As above, those of ordinary skill in the art will understand that the portable exercise devices described above with reference to the wood embodiments of  FIGS.  23 - 31  and  36 - 42    are exemplary only, and that portable exercise devices in accordance with the present disclosure may comprise various types, numbers, configurations, and/or combinations of the above described elements and features without departing from the scope of the present teachings and claims. 
     In accordance with various exemplary embodiments of the present disclosure, an exemplary method for exercising muscles in an ankle, foot, and/or leg of a user  123  using the exercise device  100 , as illustrated in the embodiments of  FIGS.  1 - 13 B , will now be described with reference to  FIGS.  1 - 14   . For use, the exercise device  100  may be placed in an open configuration, as shown in  FIG.  1 - 7 ,  13 A, and  13 B . Alternatively, during travel or when otherwise storing and/or transporting the device  100 , the exercise device  100  may be placed in a closed configuration, as shown in  FIGS.  7 - 12   . Consequently, exemplary methods for exercising in accordance with the present disclosure, contemplate that a configuration of the device  100  may be adjusted from a closed confirmation to an open configuration, wherein, as described above, in the closed configuration, the pedal  101  is collapsed against the base  102 , and, in the open configuration, the pedal  101  is raised into an elevated position with respect to the base  102  to receive a foot  121  of a user  123 . 
     The configuration of the device  100  may be adjusted from the closed configuration to the open configuration by lifting the pedal  101  off the base  102  and into a position substantially parallel to and aligned with the base  102 , such that a space S is formed between the pedal  101  and the base  102 . In various exemplary embodiments, the pedal  101  may be held in the open configuration position (neutral position) via the support  110 , which is positioned between the pedal  101  and the base  102 . As previously noted, the support  110  is connected to each of the pedal  101  and the base  102  via a respective hinge  109  and  111 . The support  110  may, for example, be raised and lowered with respect to the base  102  (i.e., transitioned between an upright and collapsed configuration as described above) by respectively securing and releasing a cord  116  that is attached to the support  110 . In other words, to raise the support  110  and maintain the support  110  in the upright configuration (and thereby raise the pedal  101  and maintain the device  100  in the open configuration), the cord  116  may be pulled taut and secured, for example, within a clamp  117 . And, to lower the support  110  (and thereby lower the pedal  101  and place the device in the closed configuration) the cord  116  may be released from the clamp  117 , such that the cord  116  is slackened to allow the support  110  to collapse against a top surface  145  of the base  102  via the hinges  109  and  111 . 
     When in the open configuration, a foot  121  of the user  123 , for example, a right foot  121  is set on the foot surface  150  of the pedal  101 . Upon initial use of the exercise device  100 , the pedal  101  may receive the user&#39;s  123  foot  121  in a neutral position N relative to a pivot axis P (see  FIGS.  6  and  7   ). As shown for illustrative purposes in  FIGS.  13 A and  13 B , using for example a right foot  121 , the user  123  can rotate the pedal  101  in a first and second opposite directions, F and E respectively, about the pivot axis P against a resistive force Z exerted against the pedal  101  in a direction opposite to the rotating direction (i.e., opposite to the direction F or E). For example, the user  123  can rotate the pedal  101  in the first direction F about the pivot axis P to move a first end (e.g., the toe end portion  104 ) of the pedal  101  toward the base  102 , while a force exerted (e.g., by a resistance mechanism  103 ) against a second end (e.g., the heel end portion  105 ) of the pedal  101  resists the pivoting motion. Likewise, the user  123  can rotate the pedal  101  in the second direction E about the pivot axis P to move the second end (e.g., the heel end portion  105 ) of the pedal  101  toward the base  102 , while a force exerted (e.g., by the resistance mechanism  103 ) against the first end (e.g., the toe end portion  104 ) of the pedal  101  resists the pivoting motion. In this manner, rotating the pedal  101  in the first and second directions may cause a rocking movement of the pedal  101  about the pivot axis P. Thus, as illustrated in  FIG.  13 A , rotating the pedal  101  in the first direction F may comprise depressing a toe end portion  104  of the pedal  101  and, as shown in  FIG.  13 B , rotating the pedal  101  in the second direction E may comprise depressing a heel end portion  105  the pedal  101 . 
     As explained above, in various exemplary embodiments, the amount of force exerted against the pedal  101  may vary with a degree of rotation θ of the pedal  101  about the pivot axis P (see  FIG.  14   ), for example, the amount of force exerted against the pedal  101  may increase with the degree of rotation θ of the pedal  101  about the pivot axis P. In this way, the further away from the neutral position the user  123  rotates the pedal  101 , the more force that is required by the user  123  to maintain the position of the pedal  101 . 
     Although not shown, similarly, the device may be used with a left leg/left foot of the user  123 . For example, in the same manner, the left foot may be set on the foot surface  150  of the pedal  101 . As above, the user  123  can then rotate the pedal  101  in first and second opposite directions F and E about the pivot axis P against a force exerted against the pedal  101  in a direction opposite to the rotating direction (i.e., opposite to the direction F or E). 
     Various exemplary embodiments of the present disclosure, therefore, contemplate rotating the pedal  101  in the first and/or second opposite directions F and E to subject the corresponding foot of a user to both plantar flexion motion (e.g., with reference to  FIG.  13 A , movement of the toes of the foot  121  away from the shin, thereby contracting the calf muscle) and dorsiflexion motion (e.g., with reference to  FIG.  13 B , movement of the toes of the foot  121  toward the shin, thereby stretching the left calf muscle). In this manner, using the exercise devices in accordance with various exemplary embodiments of the present disclosure can exercise both dorsiflexor and plantar flexor muscle groups, providing full flexion and extension of the ankle joint to increase blood circulation in the lower extremities of the body. 
     In various exemplary embodiments of the present disclosure, for example, rotation of the pedal  101  in the direction F may subject the corresponding foot through up to about 75 degrees of plantar flexion (e.g., rotation ranging from about neutral to 75 degrees); and rotation of the pedal  101  in the direction E may subject the corresponding foot through up to about 60 degrees of dorsiflexion (e.g., rotation ranging from about neutral to −60 degrees). 
     To demonstrate the efficacy of the devices, a clinical pilot study was performed using 12 healthy, adult volunteers. In the study, each participant used a similar device to the above device  100  to exercise, while being monitored by ultrasound Doppler using a linear probe. The subjects were seated at a sufficient height to achieve bent knees (90 degrees of flexion), with their right foot engaged with the device. Each subject rested in the seated position until blood flow parameters stabilized, after which time resting blood flow measurements were conducted. Blood vessel diameter measurements were taken using the ultrasound Doppler as visualized on the screen and the diameter was observed to remain constant before and through the exercise. Each participant then commenced with 1 minute of exercise, performing maximum effort right lower limb plantar/dorsiflexion maneuvers at 35 cycles per minute, as indicated by a metronome (i.e., wherein one cycle was defined as going from maximum dorsiflexion to maximum plantar flexion and back to the starting position). Blood flow measurements were then repeated immediately following completion of exercise, and then at 5 minutes, 10 minutes, and 15 minutes following completion of exercise. Post-exercise values for blood flow velocity and blood vessel diameter were then divided by pre-exercise values to calculate the respective ratios of each. The results of the clinical study are illustrated in  FIG.  32   , which plots the average percentage increase in blood flow over time for the participants. As shown in  FIG.  32   , on average, the participants experienced a significant improvement in blood flow velocity through the popliteal vein immediately after use, with the average increase in blood flow velocity at 1 minute being about 143%. The duration of continued increase in blood flow velocity relative to starting levels varied somewhat, but the average increase in blood flow velocity at 5 minutes was about 10%. Although the study specifically measured blood velocity, one of ordinary skill in the art, understanding the relationship between flow, velocity, and area (diameter of the vein) will understand that it is believed a corresponding increase in the volume of blood moving through the veins was realized. 
     Upon completion of an exercise session, exemplary methods in accordance with the present disclosure further contemplate that the configuration of the device  100  may be adjusted back from the open configuration to the closed configuration, for example, for storage, transport, or the like. In various embodiments, for example, the device  100  may be adjusted between the open configuration and the closed configuration by collapsing the pedal  101  against the base  102  to minimize the space S between the pedal  101  and the base  102 . As above, the pedal  101  may be collapsed, for example, by lowering the support  110  with respect to the base  102  (i.e., transitioning the support  110  between the upright and collapsed configurations as described above) by releasing the cord  116  that is attached to the support  110 . 
     It will be appreciated by those ordinarily skilled in the art having the benefit of this disclosure that the present disclosure provides various exemplary devices and methods for exercising muscles in an ankle, foot, and/or leg useful for increasing blood circulation in the lower extremities of the body. Furthermore, those ordinarily skilled in the art will understand that the disclosed exemplary devices and methods for exercising muscles in an ankle, foot, and/or leg may have other benefits and may treat other conditions, including, but not limited to, peripheral vascular disease, such as peripheral artery disease, PAD, and chronic venous insufficiency. 
     Further modifications and alternative embodiments of various aspects of the present disclosure will be apparent to those skilled in the art in view of this description. For example, although the particular examples and embodiments set forth herein contemplate an exercise device that receives one foot at a time, various additional exemplary embodiments in accordance with the present disclosure contemplate an exercise device that receives both feet at once, thereby simultaneously exercising muscles in both ankles, feet and/or legs. 
     Furthermore, the devices and methods may include additional components or steps that were omitted from the drawings for clarity of illustration and/or operation. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the present disclosure. It is to be understood that the various embodiments shown and described herein are to be taken as exemplary. Elements and materials, and arrangements of those elements and materials, may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the present disclosure may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of the description herein. Changes may be made in the elements described herein without departing from the spirit and scope of the present disclosure and following claims, including their equivalents. 
     It is to be understood that the particular examples and embodiments set forth herein are non-limiting, and modifications to structure, dimensions, materials, and methodologies may be made without departing from the scope of the present disclosure. 
     Furthermore, this description&#39;s terminology is not intended to limit the present disclosure. For example, spatially relative terms—such as “beneath”, “below”, “lower”, “above”, “upper”, “bottom”, “right”, “left” and the like—may be used to describe one element&#39;s or feature&#39;s relationship to another element or feature as illustrated in the figures. These spatially relative terms are intended to encompass different positions (i.e., locations) and orientations (i.e., rotational placements) of a device in use or operation in addition to the position and orientation shown in  FIGS.  1 - 12   . 
     For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing quantities, percentages or proportions, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about” if they are not already. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. 
     Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the present disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Moreover, all ranges disclosed herein are to be understood to encompass any and all sub-ranges subsumed therein. 
     It is noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the,” and any singular use of any word, include plural referents unless expressly and unequivocally limited to one referent. As used herein, the term “include” and its grammatical variants are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that can be substituted or added to the listed items. 
     It should be understood that while the present disclosure have been described in detail with respect to various exemplary embodiments thereof, it should not be considered limited to such, as numerous modifications are possible without departing from the broad scope of the appended claims, including the equivalents they encompass.