RECOVERY OF ELECTRICAL STIMULATION FORCE AFTER ONE-MINUTE OF MAXIMAL HOPPING AND CYCLING

Abstract

INTRODUCTION Recovery of electrical stimulation force depends on a type of peripheral muscular fatigue. Low frequency force, designated to a low frequency fatigue, may recover in a few hours after the workout, while a recovery of a high frequency force, designated to a high frequency fatigue, ends in a few minutes after the workout (Cooper et aJ., 1988). The aim of the present study was to examine a recovery of electrical stim01ation force at 20 Hz and 100 Hz after one-minute of a 'maximal hopping on a force plate and cycling on a Monark ergometer. Eleven students of physical education (age 22. 9± 3.9 yrs, height 176.1 ± 4.1 cm, mass 71.8 ± 3.7 kg) performed both tests on separate weeks. Relaxed vastus lateralis museie (VL) was electrically stimulated before and 1., 2.,3.,4.,5.,6.,7., and 10. minute after the end of the workout and the isometric knee torque during stimulation was measured. Statistically significant changes to the pre-workout result were tested with a two-way student-test. Post-workout results were afterwards normalised to the preworkout torque. Asterisks denote a statistically significant change according to pre-test state (* -P<0.05, ** -P<0.01, *** -P<0.001). CONCLUSION Each activity in presented form resulted in its distinctive fatigue response: hopping in a high frequency fatigue and cycling in a low frequency fatigue. Even though, the recovery of electrical stimulation torque in the first few minutes seemed to have a similar time course: returning to the preworkout level between the second and the third minute and displaying a potentiation afterwards, which was short at cycling but still rising after 10 minutes at hopping. REFERENCES Cooper, R.G., Edwards, R.H.T., Gibson, H., Stokes. M.J. (1988) Human muscle fatigue: frequency dependence of excitation and force generation. J. Physiology 299: 465 486.