Abstract:
A power ladder for exercising and fitness is disclosed. Embodiments of the power ladder are lightweight and compact, and fold for easy storage and transport. Embodiments include two flexible plastic side rails and a plurality of rungs connected to the side rails at intervals along the side rails. The rungs connect pivotally and slidably to the rails. The rungs are mounted on telescoping legs so that the rungs may be used in a first position adjacent the ground, in a second position above the ground, and in some embodiments, a third position, mounted higher above the ground than the second position. Using the ladder, persons can train for agility, flexibility and plyometrics, and can thus achieve excellent exercising while having fun. One or more persons or even a team may use the ladder. Larger teams may compete using one ladder or more than one of the ladders.

Description:
PRIORITY CLAIM 
     The present application claims priority to, and the benefit of, U.S. Provisional Appl. No. 61/292,427, Methods and Systems of a Power Ladder, filed on Jan. 5, 2010, under the provisions of 35 U.S.C. §119, the contents of which are hereby incorporated by reference in their entirety. 
    
    
     FIELD 
     The field of the present disclosure is that of exercise devices, and in particular exercises which are used for both speed and agility training and also strength training, with an emphasis on plyometrics. 
     BACKGROUND 
     Regular physical activity, fitness and exercise are important in leading a healthy lifestyle and preventing disease. A recent report from the Department of Health and Human Services (HHS), Office of the Assistant Secretary for Planning Evaluation, details many of the benefits of an active lifestyle, while also listing many of the consequences of leading a sedentary lifestyle. The report is entitled, “Physical Activity Fundamental to Preventing Disease,” and was published on Jun. 20, 2002. This report includes many facts and figures on the health costs of an inactive lifestyle, especially when combined with consequences of an unhealthy diet. 
     As stated in the report, regular physical activity has been shown to reduce morbidity and mortality from many diseases, especially chronic diseases. Such diseases can be prevented or improved through regular physical activity. For example, 14 percent of all deaths in the United States have been attributed to activity patterns and diet, according to the Journal of the American Medical Assn. (JAMA),  Actual Causes of Death in the United States,  270(18):2207-12 (1993), J. M. McGinnis and W. H. Foege. As also stated in the HHS report, 12.6 million Americans have coronary heart disease and 1.1 million people suffer from a heart attack in a given year. About 17 million Americans have diabetes, of which 90-95% is type 2 diabetes, which is associated with obesity and physical activity. Perhaps even more alarming, approximately 16 million people have pre-diabetes. It is estimated that about 50 million people have high blood pressure, according to the American Heart Association, 2002 Heart and Stroke Statistical Update. 
     The HHS report also notes that most adults and many children lead a relatively sedentary lifestyle and are not active enough to achieve the benefits known to accrue to those who are physically active. On a more positive note, persons with a healthier lifestyle live an average of 6 to 9 years longer. JAMA 1999; 282:2012-2018,  Low risk - factor profile and long - term cardiovascular and noncardiovascular mortality and life expectancy  (findings for 5 large cohorts of young adult and middle-aged men and women), J. Stamler, R. Stamler and J. D. Neaton. These people also tend to postpose disability by 9 years, and tend to compress any disability into fewer years at the end of their life. N. Engl. J. Med. 1998; 338:1035-1041,  Aging, health risks, and cumulative disability , A. J. Vita, R. B. Terry, H. B. Hubert, J. F. Fries. 
     As reported elsewhere, up to 55% of Americans do not get enough physical exercise, while about two-thirds of Americans are overweight or obese. Centers for Disease Control and Prevention,  Prevalence of Physical Activity, Including Lifestyle Activities Among Adults—United States,  2000-2001, MMWR 2003; 52(32):764-769, available on line at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5232a2.htm; JAMA 2002; 288:1723-1727 , Prevalence and Trends in Obesity Among US Adults , 1999-2000, K. M. Flegal, M. D. Carroll, C. L. Ogden, C. L. Johnson. 
     It seems clear, then, that more Americans should be exercising regularly and also should participate generally in more healthy lifestyles and with better nutritional practices. One way to encourage regular exercise is to make exercising fun. It would also be beneficial if any equipment used for exercising is both useful and inexpensive. One way to exercise involves equipment generally known as exercise ladders. Exercise ladders generally resemble ladders used for climbing, in the sense that both have long side rails joined by rungs or cross pieces at intervals along the side rails. Exercise ladders are typically made from very thin or flexible materials and are not capable of supporting body weight. Exercise ladders are typically laid on the ground. 
     A person uses an exercise ladder by running or jumping between the rungs to increase both speed and agility. With several ladders laid adjacent one another, teams or sports clubs can run agility drills while introducing an element of competition at the same time. For example, squads or teams can compete in completing a certain exercise or agility drill, with the first team to complete the drill winning the competition. The drills may include such routines as each player running through the ladder one way or both ways; the routines may vary the number of rungs completed or skipped, and so forth. 
     These exercises can be very physically demanding. However, after several exercises, it would be good if there were a variation of the ladder routine available to the competitors. Such variations would help keep the exercise and the competition fresh for the participants. Any such variations should fit easily into an exercise ladder and should be relatively inexpensive in order to keep help keep this equipment within a reasonable price range for all consumers. 
     SUMMARY 
     One embodiment is an exercise ladder for use atop a playing surface. The exercise or power ladder induces two side rails, a plurality of rungs connecting the two side rails at intervals along the side rails, a plurality of legs between the plurality of rungs and the side rails, and a plurality of pivot hinges connecting the plurality of rungs to the plurality of legs, wherein each rung of the plurality of rungs is connected independently to the side rails, and each leg has a first lower position and at least one raised position above the ground. 
     Another embodiment is an exercise ladder for use on a playing surface. The exercise ladder includes two side rails, a plurality of rungs connecting the two side rails at intervals along the side rails, a plurality of telescoping legs between the plurality of rungs and the side rails, and a plurality of pivot hinges connecting the plurality of rungs to the plurality of telescoping legs, wherein each rung of the plurality of rungs is connected independently to the telescoping legs, and wherein each telescoping leg has a first flat position adjacent the ground and at least one raised position above the ground. 
     Another embodiment is an exercise ladder for use on a playing surface. The exercise ladder includes two side rails, a plurality of rungs connected to the two side rails at intervals along the side rails, a plurality of telescoping legs, a plurality of pivot hinges connecting the plurality of telescoping legs to the rungs, and a plurality of spring hinges connecting the plurality of telescoping legs to the side rails, wherein each rung of the plurality of rungs is connected independently to the side rails, and each rung has a first flat position adjacent the playing surface and at least one raised position above the ground. 
     This disclosure includes a number of embodiments, and is intended to be descriptive of any number of embodiments, rather than limiting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  depicts an isometric view of a first embodiment. 
         FIG. 2  depicts a person using a first configuration of the embodiment of  FIG. 1 . 
         FIGS. 3A-3E  depict component parts of an embodiment of a power ladder. 
         FIGS. 4A-4D  depict different positions of the embodiments of  FIGS. 3A-3E . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  depicts a Power Ladder set up for use by a person. Power ladder  10  includes two side rails  12  and a plurality of rungs  14 . Each rung  14  includes a leg  16  on each side for connection to a side rail  12 . In this embodiment, each leg  16  includes a lower leg  17  connected to the side rail  12  and an upper leg  18  which is connected to a rung  14 . The upper leg  18  may contain detents  19   a  for placement in orifices  19   b  of the lower leg  17 . The detents reside within upper leg  18  and may have spring loaded portions which fit into the orifices  19   b . Thus, each rung  14  may be positioned independently and may be in a flat position or in a raised position. In addition, the legs may be designed so there is more than one raised position. For example, in one embodiment, the legs may be raised to a first height of about 6 inches above the ground or side rails  12 , and to a second height of about 9 inches above the ground. Other embodiments may have only a single raised position. Yet other embodiments may have three raised positions. The flat position may be adjacent the ground. For example, in one embodiment, the rung may have a hollow portion adjacent the ground, the hollow portion includes a space sufficient to accommodate the height of the rail adjacent the rung. Thus, in this embodiment, when the rung is in a lowered position, the bottom surface of the rung touches the ground and the portion of the side rail adjacent the rung is captured by the rung. 
     The up or down position of each rung may be adjusted by the person using the power ladder. The power ladder helps people to gain speed and agility as they run drills through the spaces between the rungs. The power ladder also helps people with plyometrics, that is, with strength training With the rungs all set in a down position, a person can optimize foot speed and agility training by being able to change speed and direction as quickly as possible without worrying about stepping sufficiently high to avoid raised rungs, i.e., hurdles. There are also proprioceptive and kinesthetic aspects to power ladder training as one&#39;s mechanoreceptors adjust the body&#39;s awareness in space. As more rungs are raised, more of the exercises are directed toward plyometrics and generating power. However, proprioception is still highly required and developed further because a person has to perceive and jump over the hurdle and land before taking the next step. 
     As one steps through the exercise ladder or power ladder, more muscles and more muscle power are needed to step through the spaces between the raised rungs or hurdles. Muscules then tend to develop in order to generate the force needed to move the body over the hurdle and then step again as the foot comes back in contact with the ground.  FIG. 2  shows a person P using power ladder  10 . The person is performing a two legged hop over a hurdle then transitioning into two successive agility footwork movements followed by more repetitive plyometric movements. 
     As the person varies the position of the rungs, some raised and some lowered, a different rhythm is required for the exercise. A maximum of awareness and agility may be required when every second rung is raised, with the remainder being in a lowered position. A different level of awareness and proprioception is required when all rungs are raised, and the person must step high between each rung to complete the agility drill. Alternatively, the person could require jumping from one space to the next as the person goes through the drill. In short, the variations of exercises possible are virtually unlimited with this exercise or power ladder. 
     Also contributing to the utility of embodiments of the power ladder is the ease with which each rung is raised or lowered, as explained with reference to  FIGS. 3A-3E  and  4 A- 4 C. In one embodiment, each rung  20  is supported on each side by a telescoping leg. As shown in  FIGS. 4A-4C , the telescoping legs may have three positions, e.g., stowed within the rung, extended partially, or extended fully. As shown in  FIGS. 3A-3E , in one embodiment, legs may include a pivot hinge, upper and lower leg portions, and a spring hinge connecting the lower leg portion to the side rail on that side of the power or exercise ladder. The pivot hinge connects the upper leg portion to the rung. 
       FIG. 3A  depicts a rung  20  used in embodiments of the power or exercise ladder. Rung  20  is made from wood, plastic, or other suitable material. The rung is sufficiently long to reach from a rail on one side of the ladder to the rail on the opposite side, as shown in  FIGS. 1-2 . The rung includes a top surface  21 , a bottom surface  22 , a hollow central portion  23  and sides  24 . The hollow central portion  23  has a cross-section generally in a shape of a T, with a wider top portion and a narrower bottom portion. Sides  24  include orifices  25  for accommodating detents or other holders for legs supporting the rungs, the legs and rungs forming hurdles when in a raised position. Each side of the rung  20  also includes a stop  26  for retaining a pivot hinge within the hollow space, as discussed below. Each side may have one stop  26 , as shown, or may have a second stop opposite the first stop for more positive retention. In this embodiment, stop  26  has a hemispherical shape. Other embodiments may have other shapes. 
     A pivot hinge  30 , as shown in  FIG. 3B , connects rung  20  to the legs supporting the rungs. Pivot hinge  30  may be made of a suitable plastic or metal, or other material as desired. The pivot hinge includes an upper portion  31  with a first set of detents  40 . The detents  40  have hollow bodies  41  and may have spring loaded plungers  42 . The detent may also include a flange  43  for retention in place. When one presses on the plunger  42 , the plunger retracts, allowing for one to move the pivot hinge  30  and detents  40  within the hollow  23  of the rung. When the pivot hinge is aligned with the orifices  25 , the detents will pop out and the plungers  42  will retain the pivot hinge in place. Because the orifices  25  and plungers  42  have radial symmetry, the pivot hinge may rotate or at least pivot, allowing the pivot hinge to enter the hollow space. As shown below in  FIG. 4A , the pivot hinge has at least one additional position within the rung. Thus, the pivot hinge will pivot further when the user pushes the pivot hinge, disengaging the detents, and causing the pivot hinge and the legs into a storage position with the rung. Of course, the width of upper portion  31  is less than the distance across the width of the hollow  23  of rung  20 , so that upper portion  31  will fit into the upper part of the hollow and may be slid inwardly and outwardly in the hollow. This movement allows a user to stow the legs and to pull out and extend the legs for use in exercises. 
     Pivot hinge  30  also has a lower portion  33  with a second set of detents  40 . The second set of detents may be the same as the first set or may be different. For example, they may have a shorter body length than the first set. There is also a narrow transition portion  32  between the upper  31  and lower  33  portion of pivot hinge  30 . Upper portion  31  is depicted as having a hollow square cross-section. Other embodiments may have a hollow cylindrical cross section, or other cross section of a suitable shape. 
     The second set of detents  40  in lower portion  33  fit into orifices  54  in ears  53  of upper leg portion  50 , as shown in  FIG. 3C . Upper leg portion  50  includes a hollow, generally cylindrically-shaped body  51 , with orifices  52 . In this embodiment, the body orifices  52  are oriented at about 90 degrees from the ears  53  and the ear orifices  54 . In this embodiment, ears  53  are oriented with the long axis of the power ladder, with the orifices  52  oriented along the axis for the rungs. Upper leg portion  50  is held by the second set of detents  40  in the orifices  54  of ears  53 . 
     As shown in  FIGS. 3C and 3D , upper leg portion  50  has a larger diameter than lower leg portion  60 , which may be contained within upper leg portion  50 . Lower leg portion  60  also has a hollow, generally cylindrically-shaped body  61  and includes a single detent  40 . Detent  40  may be the same as the detents previously shown or may be different. For example, the detent may have a longer or short body length  41 . Detent plunger  42  fits within upper orifice  52  when the leg is stowed or in a partially-extended position, as shown in  FIGS. 4A and 4B . Detent plunger  42  fits within lower orifice  52  when the legs are in a fully extended position, as shown in  FIG. 4C . 
     Lower leg portion  60  may also be equipped with a spring hinge  65 . Spring hinges of many types are available, for example, from H.A. Guden Co., Ronkonkoma, N.Y., USA. Spring hinge  65  includes a first and second legs  61  and  62 , and hinged central spring  63 . Legs  61  and  62  are aligned with detent  42 . Spring hinge  65  acts as a connector to connect lower leg portion  60  to a side rail  12 . The spring hinge  65  helps to space and orient the leg with the side rail  12 . The spring hinge urges the leg, include lower leg portion  60 , away from the side rail and into an upright position. Two top views are also shown in  FIG. 3E . In the left view, side rail  12  is shown in a left-to-right orientation, with lower leg portion  60 . Lower leg portion  60  is attached to side rail  12  with spring hinge  65  using rivet  66 . Spring hinge  65  is also attached to lower leg portion  60  with a rivet (not shown). In other embodiments, the spring hinge may be attached by gluing, with fasteners, or if the parts are metal, by welding or brazing. In addition, an extra length of plastic  68  is shown underneath side rail  12 , which may also be attached to the side rail using the same rivet  66 . This length of plastic is added to lend a little additional stiffness and stability to the exercise or power ladder. Plastic length  68  may be about 1 or 2 inches wide and may be from about 0.030 inches thick to about 0.060 inches thick. Other thicknesses and widths may be used as desired. 
       FIGS. 4A-4D  depict a top or bottom elevation view of the exercise or power ladder. In these views, a one-rung portion  70  of the ladder is sequentially depicted in a stowed position,  FIG. 4A , in a partially raised position  FIG. 4C , and in a fully extended or raised position,  FIG. 4D .  FIG. 4B  depicts a side elevation view of this portion of the ladder. 
     In  FIG. 4A , rung  71  is adjacent a playing surface, such as the ground. Rung  71  includes four orifices  72  for accommodating a plunger from a detent, as discussed. As seen in this figures, the detents from pivot hinges  74  are engaged in the inner orifices  72 . A leg  73  from a left side and a leg  73  from a right side is depicted stored within the hollow space of rung  71 . Each leg  73  along includes a pivot hinge  74 . As discussed, the pivot hinge is mounted slidably within the rung, or within the hollow portion of the rung, because the upper portion of the hollow of the rung is slightly wider than the upper portion of the pivot hinge. Spring hinges  75  are closed, with the legs facing the same direction (inwardly) and the spring at maximum compression. In this view, the additional piece of plastic  76  is depicted under the rung. 
       FIG. 4B  depicts a side view of ladder portion  70 , with the legs still in the stowed position, as depicted in  FIG. 4A . In this side view, legs  73  are seen to fit within the hollow space of rung  71 , and spring hinge  75  is visible from the side. Side stop  26 , as discussed above, helps retain the leg  73  in place within the hollow. Detent plungers  42  are visible, the plungers from each side of pivot hinges  74 , similar to pivot hinges  30  in earlier figures. Note that the cross section of pivot hinges  74  is a little smaller than the hollowed-out portion on the inside of rung  71 . Leg  73  is also seen to be very close to the ground, adjacent the ground, and separated from the ground only by plastic  76  and spring hinge  75 , which forms a part of leg  73 . 
     In  FIG. 4C , the legs  73  are extended partially. Rung  71  is raised to about a 6 inch height, and the legs  73  have now left their stowed positions in rung  71  and are now deployed perpendicularly to rung  71 . Each leg  73  is now seen to include a lower portion  73   a  and an upper portion  73   b .  FIG. 4B  also shows detent  73   c  from the lower leg  73   a  extending through the upper orifice of upper leg  73   b . Pivot hinges  74  are engaged through their detents with the outer orifices of the rung. Spring hinges  75  are now open, with one leg at a right angle to the other leg. Rung  71  now is in position as a low hurdle for exercise purposes. 
     The rungs of the ladder may also be raised to a higher position, as shown in  FIG. 4D . The difference from  FIG. 4C  is that the lower legs  73   a  are now fully extended, and the detents  73   c  now engage the lower orifice of upper legs  73   b . The positions of the pivot hinges  74  relative to the rungs have not changed, and the spring hinges  75  continue to help orient legs  73  at an upright, ninety degree orientation from the side rails (not shown in  FIGS. 4A-4C ). In this position, rung  71  acts as a higher hurdle for exercise purposes, and as noted above, for plyometrics training. 
     Various exercises may help train the body for coordination, proprioception, kinesthesia, and muscular education. Movements done assist with being able to control the bodies center of gravity moving in one direction and quickly firing muscles to decelerate and change to another direction. This can be executed with this ladder. Raising the rungs of the ladder alter the movements by adding in plyometric training Plyometric training is training for an ability of muscles to generate bursts of power. With this design, by raising a rung, individual hurdles may be set up. Therefore exercises and workouts become more efficient and you can utilize less amounts of space. Also the hurdles set within this ladder are adjustable from 6 inches to 9 inches, which requires less equipment. Of course, other embodiments may use higher or lower heights, depending on the person and on the training desired. 
     This type of training may be beneficial to most every person (limiting factor are those with previous injuries or certain musculoskeletal aliments). Coordination may be a factor of re-educating the motor units within a body. As motor units begin to fire, more muscles are recruited leading to an improvement in performance and also decrease potential for injury. Also proprioception is increase in individuals creating a better awareness in space for the body. This can also lead to better performance and decrease in potential for injury. 
     While this disclosure has included several embodiments shown and described in detail, various modifications and improvements thereon will become readily apparent to those skilled in the art. Accordingly, the spirit and scope of the claims is not to be limited by the foregoing examples, but is to be understood in the broadest sense allowable by law. 
     The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) is to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. 
     While embodiments have been disclosed and described in detail, it is understood that various modifications and improvements thereon will become readily apparent to those skilled in the art. Accordingly, the spirit and scope of the present disclosure is not limited by the foregoing examples, but is better understood by the claims below.