Use of Exercise Snacks to Improve Upper Body Fitness

Study Summary

This study will examine the effects of an upper-body resistance "exercise snack" (ES) protocol on upper-body strength, endurance, and power. Participants will be randomly assigned to one of three groups: a submaximal effort repeated throughout the exercise day ES group, a maximal effort performed once per exercise day ES group, and a control group that continues usual activity (Control: no resistance exercise). Both exercise groups will perform two exercises, push-ups and planks, three days per week. The submaximal repeated effort ES group (SMR\_ES) will perform approximately 33% of the maximal number of push-ups and maintain a plank position for 33% of maximal time, three times per day. The maximal once-per-day effort ES group (MO\_ES) will perform the maximal number of push-ups and maintain a plank position for maximal time, once per day. Therefore, both ES groups (SMR\_ES and MO\_ES) will perform the same weekly volume (repetitions and time) of both exercises across the six-week intervention period. Before and after the six-week intervention period, all participants will undergo testing to assess upper-body performance. Outcome measures will include push-up endurance (maximum repetitions), plank endurance (maximum time), push-up power (assessed using force plates), and maximal push strength (assessed using hand-held dynamometry). Pre- and post-intervention changes in outcomes will be compared among all three groups. If significant changes are identified, additional comparisons will be conducted between the SMR\_ES and Control groups, as well as between the SMR\_ES and MO\_ES groups. The primary aim of this study is to determine whether repeated submaximal efforts performed three times per day, three days per week, increase upper-body endurance, power, and strength compared to a control group performing no resistance exercise. The secondary aim is to determine whether submaximal efforts performed three times per day, three days per week, produce changes in upper

Primary Outcome

Upper-body muscular strength will be assessed using a hand-held dynamometer during a standardized pushing task. Participants will push a barbell upward against an immovable strap connected to a pull dynamometer. Peak force output (Newtons) will be recorded.

Interventions

• BEHAVIORAL Submaximal Repeated Exercise Snack
• BEHAVIORAL Maximal One-Time Exercise Snack