MOBILVibrational-proprioceptive Resistance Exercise Training Versus Neuromuscular Electrical Stimulation Training in Elderly People With Muscle Weakness

Subjects in the LP group train on a custom built, computer controlled, linear electric motor powered leg press device. The so called "swinging" vibrational-proprioceptive mode is used, which means that constant velocity of the pedals (0.3 m/s and 0.2 m/s for concentric and eccentric phase, respectively) are interrupted by short stops (every 8 mm), resulting in short force peaks appearing throughout the movement. Training load is progressively increased throughout the training.

ES training is performed with a custom-built battery-powered stimulator. The subject are seated over the edge of the therapeutic table with the trunk upright and lower legs freely swinging. Two conductive rubber electrodes covered by wet sponge are placed on the anterior thigh on each side of the body. The electrode pairs are connected to the independent channels of the stimulator and the left and the right thigh are stimulated in an alternative manner. Each repetition (i.e. ES evoked muscle contraction) is evoked by a 3.5 s train (60 Hz) of electrical pulses (rectangular, biphasic, width 0.6 ms). Consecutive contractions of the same thigh are separated by 4.5 s off intervals. Maximal tolerable intensity should be used and is monitored during the training sessions. In all the subjects this should induce a tetanic contraction of the stimulated muscles.

This group only perform the same measurements as the intervention groups and lives their live as usual in between.