RESUMO
The present study was undertaken in order to investigate effects of short-term, high intensity training on the total number and histochemical properties of fast tibialis anterior, slow soleus muscle fibres and their dominant motor neurons in male rats.<BR>The animals were subjected to 4 meters of sprint-running by the operant conditioning, 12 times a day interposed with 5 minutes rest periods for 14 weeks.<BR>This training had no effect on the total number and enzyme activities of muscle fibres and dominant neurons. However, hypertrophy of FOG and FG fibres in tibialis anterior muscle was caused by the training.<BR>The conclusion, therefore, is that short-term but high intensity training causes selec. tive hypertrophy of fast twitch muscle fibres, but does not have an influence on the histochemical properties of motor units because the training is far a short period of time.
RESUMO
The purpose of this study was to investigate effects of intermittent running trainings with trot and gallop on glycogen consumption patterns of antagonistics (m. gastrocnemius and m. tibialis anterior) in male Wistar strain rats (4 weeks after birth, n=46) . The animals were devided into three groups, control (n=18), trot training (n=14), and gallop training (n=14) . In order to evaluate glycogen consumption patterns, serial sections of the muscles were stained for Myosin ATPase, DPNH-diaphorase, and Periodic acid-Schiff (PAS) reaction.<BR>The results were summarized as follows ;<BR>1) Significant change in fiber distribution occurred on both training groups, where the percentage of FOG fiber increased and there was a concomitant decrease in the FG fiber percentage. On the gallop tiaining group this effect was shown in the deep and peripheral regions of both muscles, but on the trot training group that wasn't shown in the peripheral region of m. tibialis anterior.<BR>2) According to glycogen depletion patterns after transient running exercises, during gallop the participation of m. tibialis anterior was shown a tendency to increase.<BR>3) With the trainings, decrease of glycogen consumption in muscle fiber occurred in deep and peripheral regions of the both muscles on gallop training group and in the m. gastrocnemius on trot training group.<BR>These results suggest that the trainings with different running forms have different effects on the antagonistics.
RESUMO
Wistar strain male albino rats were sacrificed at 1, 3, 5, 7, 9, 11, 13, 15, 17, 19 and 21 days of age, and the histochemical properties of nerve cell and muscle fibre were examined.<BR>We obtained the following differentiation process in the muscle with postnatal growth;<BR>phase I (newborn-7 days) undifferentiated fibre<BR>phase II (7-15 days) FT fibre ST fibre<BR>phase III (after 15 days) FG fibre FOG fibre SO fibre<BR>On the other hand, histochemical differentiation of nerve cell was recognized earlier than that of muscle fibre, and there was no redistribution of soma type with growth.<BR>Therefore, it may be said bhat histochemical differentiation process in the muscle is largely effected by the neuronal influences exerted from the lower motoneurons.
