Effects of forward tilt of the seat surface on trunk and lower limb muscle activity during one-leg wheelchair propulsion

Abstract

[Purpose] To investigate the effects of forward tilt of the seat surface on the efficiency of wheelchair one-leg propulsion. [Subjects] Subjects were 10 healthy adults (4 men, 6 women; mean age, 27.7 ± 6.1 years; height, 166.8 ± 6.5 cm; weight, 57.9 ± 12.2 kg). [Method] This study investigated the effects of forward tilt of the seat surface (0° or 10°) on the efficiency of one-leg propulsion, based on muscle activity of the rectus abdominis, internal oblique, lumbar erector spinae, lumbar multifidus, hamstring and external oblique muscles when propelling a wheelchair at 1 m/s, and the time taken to travel 10 m using one-leg propulsion at maximum effort. [Result] Time taken to travel 10 m at maximum effort was significantly shorter with forward tilt than without. Muscle activity of all the muscles except the external oblique was significantly lower with forward tilt than without. [Conclusion] Tilting the wheelchair seat forward may be useful during one-leg wheelchair propulsion for individuals with decreased ability to tilt the pelvis forward.