Comparison Of Energy Metabolism And Training Effect Of SIT Based On Double Under Rope Skipping And Cycle Ergometer

Objective:To compare the cardiovascular response and energy resource of sprint interval training based on double under rope skipping（HIT-RS）and Wingate cycle ergometer（SIC）,and to explore the effects of sprint interval training based on double under rope skipping for 6 weeks on aerobic capacity,anaerobic capacity and body fat,so as to provide a theoretical basis for a new form of sprint interval training based on whole body weight.Method:1、15 male college students from Shanghai university of sports volunteered for this study.Participants completed energy metabolism test of two protocols（based on double under and Wingate cycle ergometer）on separate days with 1 week between trials.The test method of energy metabolism was as follows:4×30s with 4min active recovery（based on Wingate cycle ergometer and double under rope skipping）,and the blood lactic acid concentration was measured at the third minute of the interval.After the last30-second all-out exercise,rest for 1 hour,and blood lactic acid concentration were collected at the 3 minutes,5 minutes,7 minutes and 10 minutes after exercise.Subjects wore K4b² and heart rate band to monitor oxygen uptake and heart rate.The aerobic metabolism(W_aer),lactic(W^[lactate])and alactic anaerobic(W_PCr)energy output was calculated from VO₂ during exercise,net lactate production and the fast component of EPOC.The total energy cost was the sum of the energy supply of the three energy systems.2、38 male college students of the rope skipping team of Shanghai University of Sports were recruited and divided into HIT-RS group（n=20）and SIC group（n=18）.During the whole experiment,the HIT-RS and SIC were respectively carried out sprint interval training based on double under rope skipping and Wingate cycle ergometer for 4×30-second with 4min interval period,3 times a week for 6 weeks.VO_2max,maximum fat oxidation rate（MFO）,Fat_max,Wingate anaerobic capacity and body fat were tested before and after training.Result:1、Energy metabolism and cardiovascular response of two SIT modes（1）Net-VO₂ in SIC was significantly higher than that in HIT-RS（P<0.05）during exercises,and there was no significant difference in VO_2peak,%VO_2max,HR_peakeak and%HR_max between two groups（P>0.05）.（2）W_aer and W^[lactate]in HIT-RS were significantly lower than that in the SIC,while W_PCrCr in HIT-RS was higher than that in the SIC,with no significant difference between the two groups（P>0.05）.The total energy consumption of SIC group was significantly higher than that of HIT-RS（P<0.05）.（3）From the relative value of energy supply,%W_PCr and%W_[lactate]had significant differences between two groups.W_[lactate]was accounting for 52.81-60.69%of the total energy consumption in SIC,while prephosphate（37.48-49.94%）and glycolysis system（31.22-44.69%）were dominant in HIT-RS.2、Training effects of two SIT modes（1）After training,SIC showed a significant improvement in VO_2max and VO_2max/kg compared with that before training（P<0.05）,while there was no significant difference in MFO and Fat_max（P>0.05）;there was no significant difference in aerobic capacity in HIT-RS compared with those before training（P>0.05）,no significant change in MFO and Fat_max（P<0.05）.There were no significant differences between two groups in aerobic capacity（P>0.05）.（2）In terms of anaerobic capacity,the peak power,average power and PD were significantly different from that before training in two groups（P<0.05）.Except for AP（W）and AP（W/kg）,there was no significant difference between two groups（P>0.05）.（3）Body fat rate was significantly lower than that before training in SIC（P<0.05）,and was no significant change after training in HIT-RS（P>0.05）.There was no significant difference in body fat rate between two groups after training（P>0.05）.Conclusion:1、Cardiovascular responses in HIT-RS are similar with those in SIC.According to the exercise intensity standards established by the ACSM,both HIT-RS and SIC are high intensity trainings;2、In energy metabolism,two SIT protocols are mainly dominant by anaerobic system,and the total energy cost of HIT-RS is less than that of SIC.HIT-RS is mainly dominant by phosphate and glycolysis,while the SIC is mainly powered by glycolysis system.3、Sprint interval training based on double under can significantly increase anaerobic capacity,but has no significant effect on VO_2max,maximal fat oxidation rate and body fat.Therefore,sprint interval training based on double under can be widely used as a training method.4、Compared with Wingate cycle ergometer,double under can be trained anytime and anywhere with only one rope which requires less space and equipment.It is possible to cause knee joint injury due to improper posture during rope skipping,so it is necessary to master correct rope skipping posture to avoid knee joint injury.