Abstract:

BACKGROUND: Supercompensation has experienced a long evolutional process, but the supercompensation rule of skeletal muscle after glycogen aerobic energy training is little reported. 
OBJECTIVE: To observe the morphological changes of skeletal muscle, and supercompensation rules of energy substances and metabolic enzymes after different cycles of swimming training under glycogen aerobic energy supply in rats.
METHODS: Totally 132 male Sprague-Dawley rats were randomized into four groups: group A (n=42), one cycle of training, low intensity training once a week; group B (n=42), two cycles of training, medium intensity training twice a week; group C: (n=42), three cycles of training, high-intensity training three times a week; control group (n=6). Firstly training group rats underwent 1-week adaptability swimming, and then 1-week swimming training, 16 minutes once. The rat gastrocnemius was stained to observe morphological changes of the skeletal muscle under light microscope immediately, at 12, 24, 36, 48, 60 and 72 hours after training. The contents of muscle glycogen, creatine kinase, and superoxide dismutase in the gastrocnemius and serum level of creatine kinase were assayed; and the changes in the skeletal muscle injury and supercompensation rules of each index were analyzed.
RESULTS AND CONCLUSION: Compared with the control group, in the group A, the muscle glycogen at 48 hours after training was significantly increased (P < 0.01), the activity of creatine kinase in the serum and tissue was decreased significantly (P < 0.05), and supercompensation occurred at 24-48 hours. The levels of muscle glycogen and superoxide dismutase in the group B were significantly higher than those in the control group (P < 0.01), the activity of creatine kinase in the serum and tissue was significantly lower than that in the control group (P < 0.05), and supercompensation occurred at 48-60 hours. In the group C, the level of muscle glycogen at 60 hours and the level of superoxide dismutase at 48 hours were significantly higher than those in the control group (P < 0.05 or 0.01), and other indexes showed no supercompensation. These results indicate that after aerobic exercise, the medium- and high-intensity training will make damage to the muscle structure, especially the heavy training. In the recovery period after exercise, the skeletal muscle morphology shows the best recovery in the medium-intensity group at 48 hours. Under aerobic energy supply of glycogen, the supercompensation of muscle glycogen and aerobic enzyme activity in the medium-intensity training group is obvious, thereafter, medium-intensity training is suitable for glycogen aerobic energy-based movement, and its supercompensation occurs at 48-60 hours after exercise.

中国组织工程研究杂志出版内容重点：组织构建；骨细胞；软骨细胞；细胞培养；成纤维细胞；血管内皮细胞；骨质疏松；组织工程

Key words: Physical Education and Training, Muscle, Skeletal, Creatine Kinase, Superoxide Dismutase