Strength training with stretch-shortening cycle exercises optimizes neuromuscular economy during functional tasks in elderly women

Aims: Decreased functional capacity during aging is associated with impaired neuromuscular function. The strength training using stretch-shortening cycle exercises (SSC) is an effective way to improve performance during functional tasks. The purpose of the present study was to compare the effects of different types of strength training in the neuromuscular economy (i.e. normalized neuromuscular activity to perform the same pre training load) during functional tests in older women. Methods: Fifty older women (67 ± 5 years) were randomly assigned into an experimental group (EG, n= 33) and control group (CG, n= 17). The training period lasted 6 weeks, in which EG was divided into traditional strength training (TG, n= 17), and rapid strength training (RG, n= 16). Results: Significant increases were observed in the 30. seconds chair-stand test in both training groups, with greater changes observed in the RG compared with TG. Significant increases were also observed in isometric strength in TG (~8%), and RG (~10.1%), as well as in the maximal neuromuscular activity of vastus lateralis and vastus medialis in the TG and RG (P< 0.05). Significant reductions were observed in the rate of rise of electromyographic signal of rectus femoris and vastus medialis in the RG after training (P< 0.05). Conclusion: The strength training including SSC exercises seems to optimize the neuromuscular economy during functional activities in older subjects.