Effects Of Crossfit Training At Different Intervals On Cardiorespiratory Function, Strength Quality And Body Composition In Male College Students

Purposes: Cross Fit,as a special physical training system,is gradually gaining popularity in China.No matter armed police soldiers,professional athletes,or physical and fitness training enthusiasts began to join Cross Fit training.In Cross Fit physical training program,the effect of training interval time on strength quality,cardiopulmonary function and body composition is not clear.Therefore,the analysis and research on different intervals of Cross Fit is of great significance for the training plan arrangement of Cross Fit trainers with different training objectives.In this study,three different intervals of Cross Fit physical training were used to conduct 8-week Cross Fit training for male college students majoring in physical education in junior years and above as exercise intervention,in order to explore the effects of different intervals of Cross Fit training on cardiopulmonary function,strength quality and body composition.Methods: Male college students majoring in physical education in Nanjing Normal University were selected as the experimental subjects(n=21).The experiment was randomly divided into three groups with seven participants in each group,which were the non-intermittent group,the intermittent 15 s group and the intermittent 30 s group.Except for the difference in interval time,the three groups had the same training movements and number of training groups.The training content adopts 8 movements for 1 round,and each training completes 4 rounds in total.The interval time between each movement and each round is the same,and the three groups are 0s,15 s and 30 s respectively.They trained three times a week for eight weeks.Before and after the experiment,the subjects' maximum oxygen intake,reverse vertical jump height,squat1 RM,bench press 1RM,squat 60 kg,bench press 40 kg,1-minute sit-up,BMI,body fat percentage and the number of groups completed the training program "Cindy" were measured.SPSS 22.0 and Excel were used to analyze and process the experimental data,and paired sample T test was used to explore the intra-group differences of each index in the three groups before and after the experiment.One-way analysis of variance was used to explore the differences between the three groups in the improvement amplitude of each index before and after the experiment.The Tukey method was used for postexperiment analysis,and the difference of improvement of each index before and after the experiment was paled between the three groups.Results: After 8 weeks of Cross Fit exercise intervention,the three groups had significant changes in the maximum oxygen intake(cardiopulmonary function),reverse vertical jump height(explosive power),squat 60 kg,bench press 40 kg,1-minute sit-up(muscle endurance),body fat percentage(body composition)and the number of Cindy completion groups.Compared with the three groups,the height of reverse longitudinal jump in the 30 s interval group increased the most(P<0.05);Squat 60 kg and bench press40 kg in intermittent 15 s group increased the most(P<0.05).Compared with the intermittent 30 s group,the 1-minute sit-ups in the intermittent 15 s group increased significantly(P<0.05),and there was no significant difference between the two groups and the non-intermittent group(P>0.05).The body fat percentage in intermittent 30 s group decreased more than that in non-intermittent 15 s group(P<0.05),and there was no significant difference between the two groups and intermittent 15 s group(P>0.05).The number of Cindy completed groups in the non-intermittent group increased more significantly than that in the intermittent 30 s group(P<0.05),and there was no significant difference between the two groups and the intermittent 15 s group(P >0.05).However,there were no significant differences among the three groups in the maximum oxygen uptake,squat 1Rm,bench press 1Rm and BMI.Conclusion:(1)Cross Fit training can effectively improve cardiorespiratory function,muscle explosive power,muscle endurance and improve body composition.(2)There was no significant difference in the improvement of cardiopulmonary function among the three groups.(3)The intermittent 30 s group can effectively improve the muscle explosive force more than the other two groups.(4)There was no significant difference in maximum strength improvement among the three groups.(5)The intermittent 15 S group was more effective in improving muscle endurance than the other two groups.(6)The body fat rate in the intermittent 30 s group was more effective than that in the non-intermittent group.(7)The non-intermittent group was more effective in increasing the number of completed Cindy groups than the intermittent 30 s group.