Objective: This study investigated lower limb muscle activity during aquatic recumbent pedalling exercises (AP) and land recumbent pedalling exercises (LP) from different angles. Methods: The participants were 10 healthy young adult men. Electromyography data of the gluteus medius, rectus femoris, biceps femoris, tibialis anterior (TA), and lateral head of the gastrocnemius (LG) were measured during AP and LP. The top of the rotation locus was set at 0°, and each rotation was divided into 8 sections of 45°. The 8 divided sections were labelled from 0° as Section I to Section VIII. Results: In the 40-rpm recumbent pedalling exercise, TA was significantly higher in sections I, VI, VII, and VIII for AP than LP; LG was significantly higher in sections II and III for AP than LP. In the 60-rpm exercise, RF was significantly higher in section VII for AP than LP; TA was significantly higher in sections V, VI, and VII for AP than LP; LG was significantly lower in sections IV and V for AP than LP. Conclusions: AP exercise at an equivalent intensity showed significantly higher lower limb muscle activity than LP at several angles.
Okagawa et al. (Tue,) studied this question.