The effects of bilateral versus unilateral strength training on leg power.

Abstract

The purpose of this study was to compare the effects of a bilateral vs. a unilateral leg strengthening program on leg power. Forty-two subjects were randomly assigned into treatment groups. The four treatment groups were C(pretested bilateral), C(non-pretested l2 bilateral). E(pretested unilateral) and E(non-pretested unilateral). l2 Cand Ewere pretested on tests of power (Margaria-Kalamen power test), ll strength (hipsled 1 RM), and speed (40 yard dash). All four groups participated in a six-week treatment phase in which Cand Cutilized l2 bilateral leg strengthening exercies and groups Eand Eused unilateral l2 leg strengthening exercises. A factoral two way ANOVA and Fisher's test of least significant difference illustrated that significant differences occured between group means on the power and strength tests. On the power test, groups Cl , C2, and E2 were found to be significantly higher than E•l (These results lead to the rejection of the hypothesis that all of the treatment group means would be equal.) The strength test showed that groups Cand E2 were equally higher than groups Cand E• Nol zl substantive association could be made between strength and power gains per group. Based on the results of this study, there are significant differences between bilateral and unilateral conditioning groups regarding power performance. Upon closer examination, evidence supports the fact that bilateral strength training is more conducive to power enhancement.