ABSTRACT
Objective To investigate the effect of point Zusanli acupuncture on serum creatine kinase (CK) and creatine kinase isoenzyme (CK-MB) in high-intensity military training soldiers and explore its possible antifatigue mechanism.Methods Sixty healthy soldiers were randomly allocated to groups A and B, 30 each. Group A received acupuncture at point Zusanli and group B, no treatment. After two weeks of treatment, two groups of soldiers separately did 5 km high-intensity running training and fulfilled the requirement of army examination. CK and CK-MB were measured in two groups before and after training and five days after training.Results In the two groups, there were statistically significant differences in serum CK and CK-MB contents between before training and after or five days after training (P<0.05). After or five days after training, there were statistically significant differences in serum CK and CK-MB contents between groups A and B (P<0.05).ConclusionsAcupuncture at point Zusanli can effectively improve bodily antifatigue ability and reduce myocardial and skeletal muscle injury caused by high-intensity exercise in military training soldiers.
ABSTRACT
We examined the effect of running training on regional cardiac myosin isozyme composition in rats. Male Sprague-Dawley strain rats (4 weeks old) were used, and divided into two groups: sedentary control (C) and trained (T) groups. The T group was trained by treadmill running (40 m/min, 1h/day, 5 days/week, for 12 weeks) . At 16 weeks old, their hearts were excised. The left ventricle was separated into the subendocardium (Endo) and subepicardium (Epi) by dissecting the ventricle at the mid-wall. The ventricular myosin isozymes were examined by electrophoresis on pyrophosphate gel under non-dissociating conditions. The results showed the following: 1) The relative heart weight of the T group was significantly higher than the C group. 2) Left ventricular myosin isozyme composition showed a region-specific distribution in the C rats, and the proportion of V3 myosin or β-myosin heavy chain in the Endo was significantly higher than that of the Epi. However, the training had no effect on the cardiac myosin isozyme in either portion. 3) The activity of citrate synthase did not show transmural gradient in the ventricle of C animals. Training had no effect on the activities of either portion. 4) The activity of lactate dehydrogenase (LDH) showed transmural gradient in the ventricle of C rats. Training-induced changes in the activity of LDH were found in both portions, therefore, training abolished the transmural gradient in the activity of LDH, suggesting a corresponding redistribution of the myocardial work load.<BR>These results indicate that running training might induce the redistribution of the myocardial work load, whereas the stimulation apparently has no effect on the regional distribution of cardiac myosin isozyme composition.
ABSTRACT
Physical activity in the growing period has been shown to be effective for increasing bone mass because immature bones are more sensitive than mature adult bones to the stimulation with mechanical stress. However, bone growth is not uniform and changes markedly at puberty. Therefore, the response of bone to exercise may differ according to the growth process. The purpose of the present study was to investigate the process of the bone response to running training, and the relationship between the bone response and serum insulin-like growth factor-I (IGF-I) and IGF binding protein-3 (IGFBP-3) levels in female rats. Thirty-three female Wistar-Imamichi rats 4 weeks of age were divided randomly into control (CON) and running training (RUN) groups for 6 and 12 weeks. Training consisted of running on a flatbed treadmill at 30 m/min for 60 min/day, 5 days/week. The bone mineral content (BMC) and bone mineral density (BMD) in the whole and five parts of the tibia were measured by a dual-energy X-ray absorptiometer (DXA) . Simultaneously, we measured serum concentrations of IGF-I, IGFBP-3, osteocalcin and 17β-estradiol. The whole tibial BMD was significantly higher in the RUN groups than in the age-matched CON groups. When BMD was analyzed at five different studied parts within the same tibia, the increase of BMD. was noted in the proximal and distal cancellous bone in the 6-week RUN group, and in the diaphysial, cortical bone, in the 12-week RUN group. Serum concentrations of osteocalcin, a marker of bone formation, were not altered by training, whereas they decreased with aging. Serum IGF-I levels in the training groups were not changed, but IGFBP-3 levels were increased significantly only in 6-week RUN rats. As a complex between IGFBP-3 and IGF-I may be more improve than free IGF-I in the bone formation, the high levels of IGFBP-3 in the 6-week RUN group may induce an increase in the activity of IGF-I. There was a significant positive relationship between serum IGF-I concentration and BMD of the whole tibia in the 6-week study, and between the IGFBP-3 level and BMD in both the 6 and 12-week studies.<BR>In conclusion, 1) the process of the skeletal response to running training is site-specific within the same bone, and 2) the increment of the IGFBP-3 level with training in the growth period may reflect the increment of tibial BMD through training.
ABSTRACT
To clarify the relationship between cardiac myosin isozyme composition in running-trained rats and the sympathetic nervous system, we examined whether the sympathetic nervous system could contribute to the modulation of cardiac myosin isozyme in running-trained rats, using atenolol, a selective blocker of cardiac β<SUB>1</SUB> adrenegic receptor. Male Wistar strain rats (4 weeks old) were used, and divided into four groups: control sedentary (CS), control trained (CT), atenolol sedentary (AS), and atenolol trained (AT) . The AS and AT groups were treated with atenolol in drinking water (65 mg/kg/day) for 9 weeks. The CT and AT groups were trained by treadmill running (at 30 m/min for 1 h/day, 5 days/week), starting at 7 weeks old, for 6 weeks. At 13 weeks old, the hearts were excised. The left and right ventricular myosin isozymes were examined by electrophoresis on pyrophosphate gel. The results showed the followings: 1) In the CT and the AT groups, the citrate synthase activities of the plantaris muscle were increased by 26% compared with the CS group (p<0.05) . 2) In the CT group, the running training had no effect on the myosin isozyme composition, in both ventricular muscles. 3) In the AS group, the atenolol treatment resulted in a decrease in the proportion of the V1 myosin and in an increase in that of the V3 myosin. Therefore, the proportion of the β-myosin heavy chain (MHC) in both ventricles of the AS group showed a significant increase compared with the CS group (p<0.05) . 4) The AT group showed a marked increase in the proportion of the β-MHC in both ventricles, compared with that of the AS group, especially in the left ventricle (p<0.05) .<BR>From the results presented here, we did not observe any effect of the sympathetic nervous system on cardiac myosin isozyme composition in the running-trained rats.<BR>It is generally accepted that hemodynamic overload results in an increase in the proportion of β-MHC, and in contrast, the stimulation of the sympathetic nervous system induces an increase in α-MHC. Therefore, we speculated that the effect of running training on cardiac myosin isozyme composition was induced by the effects of both the sympathetic nervous system and hemodynamic overload. Consequently, running training had apparently no effect on myosin isozyme composition.
ABSTRACT
The purpose of this study was to investigate the effects of running training on bone formation in rats in relation to the age training started. The first experimental period was set from 6 to 12 weeks (wks) old and the second from 12 to 19 wks old. Sixty-four Wistar strain 6-wk-old male rats were initially divided into a non-exercise (N) and an exercise (E) group. At 12 wks old, each group was subdivided into two groups, providing four groups: non-exercise·non-exercise (NN), non-exercise·exercise (NE), exercise·non-exercise (EN) and exercise·exercise (EE) . Exercise consisted of treadmill running at a speed of 30 m/min, 60 mm day, 5 days wk. The animals were sacrificed before the experiment (6 wks old), post-first experiment (12wks old) and postexperiment (19 wks old), the bilateral tibiae were removed and their lengths, bone mineral content (BMC), bone mineral density (BMD) and bone histomorphometric parameters were measured. The tibial length was significantly shorter in 12-wk-old E than N rats and in 19-wk-old EE than NN. At 19 wks old, the total tibial BMD values were significantly higher in EE than NN, and the BMD values of the proximal and distal tibiae, where the cancellous bone was the main component, had increased markedly, whereas no differences between the diaphyseal BMD of each group were noted. Bone histomorphometry at 12 wks old, considered the immature period, showed that the osteoid surfaces and labeled surfaces tended to be increased by running training, but the bone volume was unchanged. In contrast, at 19 wks old, considered the early mature period, the osteoid surfaces showed a tendency to decrease and labeled surfaces to increase and consequently the bone volume increased albeit not significantly. These results suggest that: 1) running training started in immature rats represses longitudinal tibial growth, 2) the cancellous bone is more sensitive then the cortical bone to this type of training and 3) training of early mature rats increases bone volume by increasing the efficiency of osteoid calcification.
ABSTRACT
Four myosin heavy chain (MHC) isoforms were detected in rat hind-limb fast muscles. MHC isoforms are particularly good candidates for fiber type-specific markers in myofibril proteins. We studied the effect of running or jumping training on MHC isoform composition in 18, 6 month-old female rats. The animals were divided into three groups : sedentary (S; n=6), running (R; n=5) and jumping (J; n=7) at 4 months of age. Animals in group R were trained with treadmill running (30 m/min, 60 min/day and 5 days/wk) for 8 weeks. Animals in group J were trained with vertical jumping (40 cm high, 100 repetitions/day, 5 days/wk) for 8 weeks.<BR>There was no significant difference in body weight among the groups. Muscle weight and muscle weight/body weight for the plantaris were significantly increased in both trained groups, but there was no significant difference in the protein concentration. With regard to MHC isoform composition, there was no significant difference in the compositions of the type I and type ha MHC isoforms. In the type lid MHC isoform, the values for both trained groups were significantly higher than that of group S (p<0.05) . The values for both trained groups in the type lib MHC isoform were lower than that of group S. In particular, there was a significant difference between groups S and J (p<0.05) .<BR>These results indicate that a relative increment of the type lid MHC isoform is a typical adaptation phenomenon of the olantaris muscle in rats riven runninr and iumoinr training.