The Effects Of Supplement Of Low Glycemic Index Sports Drinks On Male College Students’ Glucose And Lipid Metabolism During Exercise

Objective:To observe Effect of low glycemic index drink supplement on the immediate sprint time of male college students after exercise in a moderate-intensity exerciseMethods:10 healthy young men are selected to repeat the test three times, for each time the test takes three weeks with each test interval of one week. On the test day the test takers have a standard breakfast (total calories 528.5 kcal, carbohydrates, fats, proteins for energy ratio of 3.4:1.2:1). They will also take in one of the following sports drinks before and during the excise:high glycemic index (HGI, GI=88), low glycemic index beverage (LGI, GI=47) and the same concentration of placebo (PLA).Supplementary amount of sugary drinks 1g/kg body weight, the control group are supplemented with the same amount of placebo which has similar appearance and taste with sugary drinks three times, namely,30 minutes before exercise,20 minutes during exercise, and 40 minutes after exercise. After a drink intake, the test taker will exercise on power bicycles (Monark 839E, Sweden) at a 60% V02max intensity for one hour, ending immediately to 80% V02max intensity sprint to exhaustion and record the sprint times. Respectively, in a quiet, immediately after exercise, one hour after exercise,2 hours after exercise and 24 hours after exercise, venous blood plasma are taken to test the glucose (Glu), insulin (Ins), free fatty acid (FFA), triglycerides (TG), Lipoprotein lipase(LPL), High density lipoprotein(HDL), Low density lipoprotein(LDL).Results:(1) The blood glucose level of athletes who have exercised for one hour after drinking HGI and LGI beverage was significantly higher than those in the control group(P<0.05); what’s more, the immediate blood glucose level of athletes in HGI group is significantly higher than those in the control group (P<0.05); the immediate insulin level of HGI group after exercises were significantly higher than the control group(P<0.05), and the one-hour insulin levels of HGI and LGI group after exercises are significantly higher than the control group (P<0.05); the immediate and two-hour free fatty acid levels of LGI group after exercises are significantly lower than the control group (P<0.05); the immediate triglyceride level of LGI group after exercise is significantly lower than the control group (P<0.05).(2) The two-hour insulin level of athletes who have drunk HGI beverage after exercises is significantly higher than those who have drunk LGI beverage in LGI group (P<0.05).(3) The average sprint time of LGI group is 20.44s longer than HGI group, and 38.78s longer than the control group, and the average sprint time of HGI group is 18.34s longer than the control group, but three kinds of beverage have no significant effects on sprint time.Conclusion:Replenishing LGI sports beverage is able to help maintaining stable blood glucose level during and after exercises and to reduce insulin response during exercises in the moderate-intensity exercises. Replenishing LGI beverage before and during exercises can speed up the fat mobilization, promote the decomposition of triglycerides and improve the utilization of FFA. Replenishing LGI beverage during prolonged exercises can save glycogen and help extending the sprint time.