The Effects of Resistance Training on Lower and Upper Body Strength Gains in Young Women

Abstract

It has been reported that hypertrophy gains is greater in upper body compared to lower body, however, there is no consensus that muscular strength gains are greater in upper body than in lower body. Therefore, the aim of the present study was to compare the strength gains between knee extensors and elbow flexors in response to similar resistance training regimens. Fifty five untrained young women (age: 21.6 ± 2.9 years, weight: 58.3 ± 9.0 kg and height: 163.6 ± 7.5 cm (Mean±SD)) participated in the study as volunteers. Resistance training was performed twice a week for 10 weeks. All subjects performed three sets of 8-12 maximum repetitions for leg press, knee flexion, lat pull down and bench press exercises. Unilateral knee extensors and elbow flexors peak torque (PT) were measured before and after the training period by performing two sets of four repetitions at 60°s^-1, on an isokinetic dynamometer. There were significant increases in PT for both elbow flexors (11.74% [8.0, 17.7], p< 0.05) and knee extensors (11.45% [9.2, 15.3], p< 0.05) with no differences between muscle groups p> 0.05). However, there was no correlation between gains in knee extensors and elbow flexors PT. The analysis of knee extensors PT lead to the formation of two clusters groups: 1) High responders (n=10): 28.29 ± 8.74% and 2) Low-responders (n=37): 7.94 ± 5.95%. Both groups had significant increases in knee extensors PT, however, increases in the high responders were higher than in low responders (p< 0.05).These results suggest that upper- and lower body muscles present similar strength gains after similar resistance training regimens in untrained young women, although individual muscle response may vary in upper and lower body muscles.

Keywords: Knee extensors, Elbow flexors, Peak torque