Figure 1. The body (A) and EDL (B), SOL (C) muscle weights were determined in young and old rats after 6 weeks of exercise training. The values are presented as mean ± standard deviation of animals per group (p < 0.05). The groups are young control (YC), old control (OC), single long-duration exercise-trained (OS1; 5 days·weeks–1, 1×30 min/day, OS2; 3 days·weeks–1, 1×30 min·day–1), and multiple short-duration exercise-trained (OM1; 5 days·weeks–1, 3×10 min·day–1, OM2; 3 days/weeks, 3×10 min·day–1). EDL muscle; extensor digitorum longus, SOL muscle; soleus. The symbols * indicates = significantly different from the OC group (p < 0.05).