Summary: | 碩士 === 國立師範大學 === 體育學系 === 86 === Leptin is closely related to body fat regulation and arouses much attention for weight control. However, the previous studies related to aerobic exercise and variables prediction have not commonly conducted. The purpose of this study was to investigate the effects of a 30-minute bicycle exercise on serum leptin levels of male university students. In addition, the body mass index (BMI)、waist to hip ratio(WHR) and percent body fat were measured to predict the leptin levels and determine their relationship. 35 male university students(age 21.77±1.14 yrs) were randomly assigned into experimental (25 subjects) and control(10 subjects) group. After 12 hours of fasting, the experimental subjects performed 30-minute bicycle exercise with intensity of 50-85% HRRmax, while the control subjects did not exercise at the same period of time to adjust the daytime variation of leptin. The blood samples were collected before and after exercise for leptin analysis by RIA-kit assay. All the data were analyzed by paired t-test, one-way ANCOVA, and stepwise regression analysis. The result of this study followed:(1) Leptin levels deceased 0.50±1.24(ng/ml) in experimental group after exercise, but not significantly different between pre-exercise and post-exercise(4.80±7.62 vs. 4.31±6.53,p>.05). In control group, leptin levels also deceased 0.56±1.01(ng/ml) , but not significantly different between pre-test and second-test(4.49±6.67 vs. 3.93±5.70,P>.05). However there was no significantly between two groups(P>.05).(2) There was a significant correlation between serum leptin levels and BMI(r=.832,P<.05), and WHR(r=0628,P<.05), and percent body fat (r=.844,P<.05). The best predict variance for leptin levels is BMI, and the prediction formula is leptin levels(ng/ml)=1.55×BMI-33.09(R2 =.8445,P<.05).Conclusion:There was no effect of 30-minute acute bicycle exercise on leptin levels, and there was a positive correlation between serum leptin levels and BMI, and WHR, and percent body fat.
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