Back and lower limb muscle activities in a prone leg holding exercise

The focus of this study was to investigate the electromyographic (EMG) activity level of two back muscles and two lower limb muscles during a leg holding exercise in strapped (supported) and unstrapped positions. The strapped position is usually used in clinical situations while the unstrapped position is commonly adopted by the patient in the home environment. Muscle activity of the longissimus thoracis, multifidus, gluteus maximus and biceps femoris muscles of 15 healthy young males was recorded by surface electrodes. During the leg holding exercise in the strapped position, normalized EMG activity of longissimus thoracis (64%) and multifidus (71%) were shown to be higher than that of gluteus maximus (39%) and biceps femoris (47%). Similarly, higher activity of longissimus thoracis (66%) and multifidus (67%) than that of gluteus maximus (43%) and biceps femoris (46%) was found in unstrapped position. No significant differences were demonstrated in the activity of the back and lower limb muscles between strapped and unstrapped positions. The present study may suggest that more training effect will be expected for back muscles than for lower limb muscles when using leg holding as a training exercise. The leg holding exercise using hands for stabilization (common in home environment) may be regarded as effective as the exercise stabilized with straps (common in clinical situations).