Repetition Prescription Approaches Delivered Via Videoconferencing
Condition: Health Behavior
Study type: Interventional

Summary: 
      A randomized controlled trial comparing between two approaches of prescribing
      repetition-numbers in resistance training (RT) sessions on psychological, physiological, and
      performance outcomes. Sixty healthy and sedentary adults (age range: 18-45) will be randomly
      allocated to either the "predetermined" or "self-selected" groups. The groups will differ in
      the amount of choice they will be able to make concerning the resistance of each exercise and
      the number of repetitions they complete (see detailed description). Both groups will complete
      two sessions per week composed of body weight and resistance band exercises, lasting 45
      minutes for eight weeks. The sessions will be delivered live by a certified instructor using
      a videoconferencing platform.

      The primary aim of this study is:

      Compare between the "predetermined" and the "self-selected" repetition prescription
      approaches on psychological, physiological, and performance outcomes in a cohort of 60
      healthy and sedentary adults (age range: 18-45) over an eight-week period of live,
      videoconferencing RT sessions.

      The secondary aim is:

      Determine the influence of live, videoconferencing group RT sessions on psychological,
      physiological, and performance outcomes across groups.
    

Detailed description: 
      Background:

      Providing trainees with more choices in exercise sessions is an autonomy supportive process
      which can lead to a more enjoyable experience, greater adherence to the training program and
      preferable performance outcomes. We will compare between two approaches to prescribing
      repetition-numbers in resistance training sessions- the "predetermined" and the
      "self-selected", based on the amount of choice trainees receive while training. Sixty healthy
      and sedentary adults (age range: 18-45) will train bi-weekly for 45 minutes using resistance
      bands in a live, videoconferencing group setting.

      Intervention details:

      The intervention will last eight weeks and include bi-weekly, 45-minute online sessions
      instructed by two alternating experienced instructors. Each session will include an
      introduction and setup (5-minutes), warm-up (5-minutes), body-weight and resistance band
      exercises (30-minutes) and cool down (5-minutes). We will upload the study protocol to an
      external server for more details.

      Both groups will follow the exact same exercise program with one key difference: participants
      in the "predetermined" group will be instructed to complete 10 repetitions per set and
      exercise, while aiming to reach a rating of perceived exertion (RPE) of 7/10 by the 10th
      repetition. This means that participants will need to select and adjust the resistance of
      each exercise (e.g., band's resistance) to achieve this goal. Conversely, in the
      "self-selected" group, participants will choose the initial resistance in view of their
      preferences, and complete as many repetitions as they wish in order to reach the same target
      RPE of 7/10. Note that while the initial resistance, and thus, the number of repetitions is
      expected to differ between group, both are matched for perception of effort.

      Recruitment and procedures:

      Participants will be recruited via social media (i.e., Facebook Inc., Menlo Park, CA, USA).
      Each candidate will be screened for initial eligibility. After screening participants will be
      block-randomized to the "predetermined" of the "self-selected" groups, matched for age and
      gender. Participants will be blind to their allocation (see concealment section). Prior to
      visiting the exercise laboratory at Tel Aviv University for the testing session, participants
      will receive written materials regarding the exercise sessions, testing procedures, and the
      use of the Rating of Perceived Exertion (RPE) scale (0-10), and a video demonstrating the
      implementation of RPE in practice. All participants that are part of a given group will be
      required to complete the first testing session within a maximum of one week before the
      program begins, and the follow up testing session within a maximum of one week after the
      program ends. Practically, one group will begin and end all procedures (i.e., initial
      testing, eight-weeks program, follow up testing) one week before the other group. The order
      of which group will begin first will be randomly decided by a coin flip.

      The initial testing session will include the following steps:

        1. Sign an informed consent form.

        2. Fill out the Basic Regulations in Exercise Questionnaire (BREQ).

        3. Body composition analysis (see outcome measures section).

        4. RPE terminology verification based on the videos and written materials delivered in
           advance.

        5. Performance tests (see outcome measures section).

        6. Practice how to use the resistance band (see below) and set up terminology to be used
           during the sessions (e.g. "open loop", "more tension").

      That same order will be kept on the final tests (excluding the informed consent), which will
      also be conducted at the same place, at the same hour-window, and by the same experimenter.

      Home-based equipment:

      Participants will receive one elastic band (NT loops, purchased from:
      (https://www.ntloop.com/shop/) as they are affordable, accessible and allow exercising in a
      controlled, safe manner. When practicing with an elastic band, changing grip width, or rubber
      stiffness allows the trainee to achieve greater or lesser resistance.

      Videoconferencing platform:

      RT sessions will be delivered using "Zoom video communications" (San-Jose, CA, USA) due to
      its popularity and user-friendly interface. Additionally, a WhatsApp group chat (Facebook
      Inc., Menlo Park, CA, USA) will be created for each group to deliver updates and reminders. A
      technical assistant from the research team will be available during the live broadcast.

      Sample size:

      This sample size is based on our recruitment abilities and resources and based on our
      previous experience with this type of intervention. A sample size of 30 participants per
      group is considered large in exercise science research with both statistically and
      practically significant effects often detected. We also expect for future meta-analyses to
      take place and for this work to be included. Thus, even if this study is currently
      under-powered for small effects, it may add valuable data to the field of exercise science.
    

Intervention name(s): RPE-based load and repetition number selection; Predetermined load and number of repetitions
Intervention type(s): Behavioral; Behavioral
Intervention description(s): Providing trainees with choices regarding the load and the number of repetitions to be performed per set and exercise; Trainees predetermine the load and perform ten repetitions per set and exercise
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Intervention group receives alternative treatment Control group receives traditional treatment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: Physical activity; Exercise adherence; Resistance training; Affective responses; eHealth; Online exercise; Self-selection; Rating of Perceived Exertion