Bicycle Simulator Training in Older Adults: A Randomized Controlled Trial
Condition: Accidental Falls
Study type: Interventional

Summary: 
      A Randomized Control Trial will be conducted with Independent old adults (age 70 years old
      and older) who willing to participate in the study. They will be randomly allocated to two
      groups: 1) Stationary bicycle riding that includes perturbation balance training during
      riding; 2) Stationary bicycle riding that does not includes perturbation balance training
      during riding. Balance and Gait assessments will be tested before and after 3 months of
      training (2-3 times a week).
    

Detailed description: 
      Falls and fall-related injuries are common elder health problems. Falls are the leading cause
      of fatal and nonfatal injuries among older adults, reducing mobility and independence, and
      increase the risk of death. Between 30 to 40% of the community-dwelling older persons fall at
      least once a year, usually by falling sideways that is resulting in 95% of hip fractures. In
      the U.S. in 2014, the estimated direct medical costs for fall-related injuries were $31.3
      billion and is expected to reach $67.7 billion by 2030 Age-related changes in the balance
      control system increase the risk of falls. Execute a rapid step, whether voluntary or
      compensatory, is the most important balance strategy to prevent a fall. In voluntary stepping
      test, the foot contact times (i.e., stepping time) and reaction time (initiation phase) were
      able to predict future fall and injury from fall. Studies of the reactive postural control
      have shown that older adults initiate stepping at lower levels of instability, use multiple
      steps, experience leg collisions or fail to recover balance compared to younger adults. The
      Medio-Lateral center of pressure sway range with Eyes Closed is the best single predictor for
      future fall.

      Studies showed that older adults were able to adapt in a reactive manner after participation
      in a Perturbations based balance training (PBBT) that challenged the mechanisms responsible
      for dynamic stability. These studies also showed a reducing in rate of falls and diverse
      risks of falls in older adults (voluntary stepping times, balance control in standing and
      walking, improved function and reduced fear of falls). however, in these studies the training
      devices and programs were designed to participants who able to walk independently the whole
      training sessions, lasting 20-45 minutes each and appropriate only for a small portion of the
      general elderly population. In fact, in 2014 in U.S., the community-dwelling older persons
      that reported a fall were divided equally into three health status: poor-fair, good, very
      good-excellent with 33% rate of fall each subgroup. This fact motivates us to provide
      accessibility PBBT for a wider range of the elderly population, and not for the "strongest"
      older subjects.

      Inspired by the well-known health advantages of cycling and the medio-lateral postural
      control demand during two-wheel bicycle riding, encourage us to conduct a preliminary study
      for feasibility. In this study we found older adults who aged with bicycle riding habits have
      benefits in reactive and predictive aspects of postural control mechanisms (particularly in
      the medio-lateral postural control) while standing and stepping, both related to risk of
      falling in the elderly (see Preliminary result section). Because the special importance of
      the medio-lateral balance control for preventing lateral falls and hip fractures in old age,
      considering our preliminary findings, we hypothesize that following exposure to training
      program that includes unexpected perturbations exercises during cycling will significantly
      improve compensatory and voluntary stepping times as well as the medio-lateral balance
      control in older adults, factors that are associated with falls and fall- related injuries.

      Objectives: firstly, to explore whether training while riding a new bicycle simulator device
      providing unexpected perturbations can reduce risks of falls in standing and walking in
      independent older adults. Secondly, if so, to examine this bicycle simulator device providing
      unexpected perturbations method in a wider range of elderly subjects (i.e., who do not walk
      independently or walk for only short distances or with assisted devices or suffering from
      fear of falling or in pre-walking rehabilitative phases after stroke or other morbidity).

      Methods Study design: A double blinded randomized controlled trial. Participants: Relatively
      healthy Community dwelling older adults that are 70 years or older, independent in daily
      living activities, walking without assistive devices, without morbidity that influence
      balance performance. The study will be approved by the Helsinki committee of Barzilai
      University medical center, Ashkelon, Israel. All subjects will sign an informed consent
      statement.

      Training programs: We will use two identical exercise bicycles, one will remain a stationary
      Bicycle device for the control group, and bicycle simulator device providing unexpected
      perturbations during a bicycle simulator riding for the experimental group. The intervention
      Group will receive 24 bicycle simulator device providing unexpected perturbations sessions,
      twice a week for 12 weeks (about 20 min. each). The subjects will be instructed to "ride on
      the bicycle in your preferred pace and try to stabilize yourself". To prevent injury if loss
      of balance occurred during the cycling, the subject will wear a loose safety harness that can
      arrest the fall. The bicycle simulator device providing unexpected perturbations program will
      have 24 levels of difficulty with increasing levels of perturbations (i.e., increase
      displacement, velocity and accelerations of the translations). The control group will receive
      24 sessions, twice a week for 12 weeks, about 20 minutes' bicycle riding on the stationary
      device, pedaling in subject own preferred pace without perturbations and wearing a loose
      safety harnesses. Since both group will train on two identical exercise bicycles, they will
      be blinded to the allocation to intervention or control group.

      Assessments: 1) Compensatory Step Execution tests during Standing and Walking: The subjects
      will be instructed to react naturally. Ten perturbation levels will be induced through a
      device that provides controlled and unexpected anterior-posterior and medio-lateral platform
      translations during a single belt treadmill in standing and walking. Four directional
      perturbations (right/left/forward/backward) in a random order each level for a total of 40
      perturbation trials. Kinematic analysis: Three-dimensional kinematic data will be collected
      through the optical motion capture, providing kinematic analysis of a motion sequence.
      Sixteen infrared cameras are covered the lab space sample simultaneously, at frequency of 200
      Hz, the location of 35 reflective markers placed on anatomical landmarks of the body and
      another two on the moving platform. The following Balance compensatory kinematics parameters:
      (1) Platform perturbation; (2) First Step initiation time (milliseconds); (3) Foot contact
      time (milliseconds); (4) Compensatory Step execution time (milliseconds); (5) Step swing time
      (milliseconds); (6) Step length (centimeters); (7) End of Compensatory steps time
      (milliseconds); (8) Total distance center of mass made (centimeters); (9) Distance of center
      of mass from leg at the step-beginning point (centimeters); 10) Arms lift initiation times
      (milliseconds); 11) Maximal arms swing amplitude/length (centimeters); 12) Arms swing times
      (milliseconds). Observational analysis: observing each trail video and identifying the
      compensatory reactions (see preliminary results). 2) Voluntary Step Execution Test:
      Participants are instructed to voluntary step as quickly as possible following a
      somatosensory cue, given randomly on one of their feet. A total of 8 trials will be conducted
      in singe task and dual task conditions (while performing the modified Stroop task). Specific
      temporal events were extracted from the step execution data: (a) Reaction Time; (b) Foot
      Contact Time; (c) Preparation Time; (d) Swing Time. 3) Postural Stability: The subjects will
      be instructed to stand barefoot as still as possible on the force platform in a standardized
      stance. Five 30-s quiet-standing trials with eyes open and five trails with eyes blindfolded.
      Evaluation of balance control will be made using both, traditional measure of postural sway
      (e.g. medio-lateral-sway, anterior-posterior -sway, sway velocity, and sway area), and
      calculating the Stabilogram-Diffusion Analysis parameters from center of pressure data. In
      addition, clinical measurements and questionnaires will be conducted as the secondary outcome
      measures: Berg Balance Scale (BBS); 6-minute walk test (6MWT); Medical History form; Late
      Life Function and Disability Instrument (LLFDI); Falls Efficacy Scale-International (FES);
      Mini Mental state examination (MMSE).
    

Intervention name(s): perturbation training
Intervention type(s): Procedure
Intervention description(s): perturbation training during stationary bicycle riding
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment
Keywords: falls; Balance control; Aging; Balance reactions; Perturbation