Low-frequency Electric Stimulation Of The Leg Muscles As A Countermeasure Of The Contractile Properties Decline Under Microgravity Conditions
- Paper number
IAC-07-A1.I.06
- Author
Dr Diliara Khusnutdinova, Institute for Biomedical Problems, Russia
- Year
2007
- Abstract
Effects of electric stimulation of leg muscles on contractile properties have been studied under conditions of dry immersion (DI). Two groups of volunteers, namely the control one (A) composed of 6 subjects and the experimental one (B), composed of 6 subjects were exposed to 7 days DI. In the A group electric stimulation of the leg muscles was applied with the low-frequency regimen, 6 hours per day. In the B group, stimulation was not used. Force-velosites characteristics of the leg muscles were studied using isokinetic dynamometry before and after DI. Force parameters declined in the leg extensors after DI in the range of low velocities, namely, 30 and 90 angular degrees by 12% and 15% correspondingly. The loss of contraction forces in leg flexors at the same time was about 10% in the range of low velocities (30 ang.deg./s) and about 20% in the range of high velocitiy (150 ang.deg./s). In the group B the force characteristics of the leg extensors after DI were not altered significantly, and were changed less significantly namely by 5% in the leg flexors. Thus data obtained point out to the fact that the low-frequency electric stimulation counteracts the negative effects of microgravity on contractile properties of the leg muscles.
- Abstract document