International Journal of Exercise Science 12(6): 691-700, 2019. Bilateral deficit (BLD) occurs when the internal muscular force generated during simultaneous bilateral limb exercise is lower than the sum of internal muscular forces generated during separate right limb and left limb unilateral exercise, while attempting to oppose the same total external load. Numerous BLD studies have evaluated force output differences during exercise; however, no study has determined whether BLD exists when generating power during isotonic upper-body exercise. To address this, we measured and compared power output across unilateral and bilateral isotonic upper-body exercise. Seventeen college male rugby players (age = 21.8 ± 2.1 y) completed 4 randomized, equal volume, upper-body exercise sessions: unilateral exercise using traditional weight training (UWT); unilateral exercise using circuit training (UCT); bilateral exercise using traditional weight training (BWT); and bilateral exercise using circuit training (BCT). Five sets of 5 repetitions of each dumbbell exercise (bench press, bent over row, overhead press, biceps curl, front raise, and bent over raise) were completed using a moderate dumbbell load (40–50% of 1-RM). Linear position transducer units were employed to measure power output. Peak and mean power scores (with the power data of all 6 exercises combined within a given group) were significantly higher in UWT compared with the other 3 protocols (p = .0001). This study involving collegiate rugby players demonstrates the presence of a bilateral power deficit in upper-body isotonic exercise and suggests that traditional unilateral exercise may generate the highest power output during a given resistance exercise session involving similar volumes of work.
Nakachi, Evan; George, James D.; Parcell, Allen; Eggett, Dennis; and Feland, Brent
"Power Output in Rugby Players Comparing Unilateral and Bilateral Isotonic Upper-body Resistance Exercise,"
International Journal of Exercise Science: Vol. 12
6, Pages 691 - 700.
Available at: https://digitalcommons.wku.edu/ijes/vol12/iss6/9