Low- and high-volume strength training induces similar neuromuscular improvements in muscle quality in elderly women

The aim of this study was to compare the effects of low- and high-volume strength training on strength, muscle activation and muscle thickness (MT) of the lower- and upper-body, and on muscle quality (MQ) of the lower-body in older women. Twenty apparently healthy elderly women were randomly assigned into two groups: low-volume (LV, n = 11) and high-volume (HV, n = 9). The LV group performed one-set of each exercise, while the HV group performed three-sets of each exercise, twice weekly for 13 weeks. MQ was measured by echo intensity obtained by ultrasonography (MQ(EI)), strength per unit of muscle mass (MQ(ST)), and strength per unit of muscle mass adjusted with an allometric scale (MQ(AS)). Following training, there was a significant increase (p <= 0.001) in knee extension 1-RM (31.8 +/- 20.5% for LV and 38.3 +/- 7.3% for HV) and in elbow flexion 1-RM (25.1 +/- 9.5% for LV and 26.6 +/- 8.9% for HV) and in isometric maximal strength of the lower-body (p <= 0.05) and upper-body (p = 0.001), with no difference between groups. The maximal electromyographic activation for both groups increased significantly (p = 0.05) in the vastus medialis and biceps brachii, with no difference between groups. All MT measurements of the lower- and upper-body increased similarly in both groups (p <= 0.001). Similar improvements were also observed in MQ(EI) (p = 0.01), MQ(ST), and MQ(AS) (p <= 0.001) for both groups. These results demonstrate that low- and high-volume strength training promote similar increases in neuromuscular adaptations of the lower- and upper-body, and in MQ of the lower-body in elderly women. (C) 2013 Elsevier Inc. All rights reserved.