A study of passive weight-bearing lower limb exercise effects on local muscles and whole body oxidative metabolism: a comparison with simulated XXXX riding, bicycle, and walking exercise.

@entity1 @entity26 @entity1641
BACKGROUND: We have developed an exercise machine prototype for increasing exercise intensity by means of passively exercising lower limb muscles. The purpose of the present study was to compare the passive exercise intensity of our newly-developed machine with the intensities of different types of exercises. We also attempted to measure muscle activity to study how these forms of exercise affected individual parts of the body. METHODS: Subjects were 14 healthy @entity1 with the following demographics: age 30 years, height 171.5 cm, weight 68.3 kg. They performed 4 types of exercise: Passive weight-bearing lower limb exercise (PWLLE), Simulated @entity1641 riding exercise (SHRE), Bicycle exercise, and Walking exercise, as described below at an interval of one week or longer. @entity26 uptake, blood pressure, heart rate, and electromyogram (EMG) were measured or recorded during exercise. At rest prior to exercise and immediately after the end of each exercise intensity, the oxygenated hemoglobin levels of the lower limb muscles were measured by near-infrared spectroscopy to calculate the rate of decline. This rate of decline was obtained immediately after exercise as well as at rest to calculate @entity26 consumption of the lower limb muscles as expressed as a ratio of a post-exercise rate of decline to a resting one. RESULTS: The heart rate and @entity26 uptake observed in PWLLE during maximal intensity were comparable to that of a 20-watt bicycle exercise or 2 km/hr walking exercise. Maximal intensity PWLLE was found to provoke muscle activity comparable to an 80-watt bicycle or 6 km/hr walking exercise. As was the case with the EMG results, during maximal intensity PWLLE, the rectus femoris muscle consumed @entity26 in amounts identical to that of an 80-watt bicycle or a 6 km/hr walking exercise. CONCLUSION: Passive weight-bearing lower limb exercise using our trial machine could provide approximately 3 MET of exercise and the thigh exhibited muscle activity equivalent to that of 80-watt bicycle or 6 km/hr walking exercise. Namely, given the same @entity26 uptake, PWLLE exceeded bicycle or walking exercise in muscle activity, thus PWLLE is believed to strengthen muscle power while reducing the load imposed on the cardiopulmonary system.
