Researches On The Mechanism, Detecting Indexs And Protective Means Of Exercise-induced Skeletal Muscle Micro-damage

1. Bases of Subject SelectingExercise-induced muscle damage (EIMD) is referred to the micro-damage of skeletal muscle fiber after organism undergoes an unaccustomed high-intensity and/or prolonged exercise. The damage of microstructure in muscle fiber, dysfunction of cell metabolism, changes of blood biochemical indices, electromyogram and the decrease of contraction function were found in EIMD. This kind of damage is characteristic of delay. It often accompanies with delay onset muscle soreness (DOMS).There are many studies on EIMD, but its occurrence mechanisms, examine means and protective measures remain to be explored further. The direct comparative studies on ischemia-reperfusion (I/R) and EIMD of skeletal muscle have not been reported. Researches showed that interleukin-6(IL-6) could be related to exercise-induced muscle damage. But it was undetermined whether IL-6 could be a examine index of EIMD. There are few studies on aspect of CK isoenzyme (CK-MM) reflects the skeletal muscle structure. And the drugs researches about how to prevent and alleviate EIMD and DOMS are still seldom carry out.2. Objectives and MethodsThis study aims to explore mechanism of EIMD further, search for the new indices that evaluate EIMD and protective means. One hundred and eighty-four SD rats were randomly divided into normal control group, middle-intensity exercise group, high-intensity exercise group (EIMD group), I/R group and exercise plus allicin group. Twenty-four athletes were randomly divided into normal control group, combined-antioxidant group and allicin group. To observe the effects of the varied-exercise intensity and allicin on EIMD in soleus and the blood IL-6, CK, CK-MM and T-AOC et al. The similarities and differences were compared between EIMD and I/R injury after a once high-intensity exercise. To comprehend the effects of VC, VE, Se and allicin on DOMS, blood indices after a high-intensity eccentric exercise. Explore the relationship between the skeletal muscle micro-damage and IL-6, CK-MM, CK-MM/CK.3. Main ConclusionsExercise stress might be the course of IL-6 increase after exercise. It is different to reflect the changes of fiber microstructure at this phase. The changes of blood plasma IL-6 indicate it has a closely relationship to EIMD when exercise stress disappear. So IL-6 could be one of indices that examine EMID. Compare to CK, the changes of serum CK-MM and CK-MM/CK ratio accord better to the changes of muscle fiber microstructure. CK-MM and CK-MM/CK ratio should be advised to be the peculiar indices. The muscle fiber structure and blood indices appear the similar changes. It shows that mechanism of EIMD and I/R have common ground, indicates I/R might be one of causes that bring EIMD. The changes of muscle fiber microstructure and blood indices of exercise plus allicin group were smaller than that of the EIMD group. These indicate allicin could alleviate EIMD. The blood T-AOC, SOD in the combined-antioxidant group and allicin group increase obviously, the increased amplitude were lower significantly than the normal control group. The muscle soreness degree alleviate after exercise. All indicate that combined-antioxidant and allicin help to alleviate DOMS and EIMD.