| Purpose The 2022 Beijing Winter Paralympics has come to an end.In this Winter Paralympic Games,the Chinese Winter Paralympic alpine skiers performed well.However,at the beginning of preparations for the Winter Paralympic,the Chinese Winter Paralympic Alpine Ski Team faced many challenges.However,at the beginning of preparations for the war,my country’s Winter Paralympic Alpine Ski Team faced many challenges.Among them,the physical reserves of athletes can not well meet the needs of the project,and there is still a big gap in strength and quality compared with competitors from other countries.At the same time,due to the characteristics of athletes with disabilities and the characteristics of the Para-alpine skiing,the technical training time has increased significantly.Especially during the competition season,competition,transfer training and technical training take up a lot of time,and physical training time is greatly reduced.According to the national team’s competition plan,during the 5-month competition(snow)season,systematic physical training can only be carried out in the 2-3 weeks between games.Therefore,how to effectively use training time and improve the efficiency and effect of physical training is the main problem faced by the national team’s physical training.Blood flow restriction training has received attention in recent years.BFR training is thought to promote muscle hypertrophy through a localized hypoxic environment and increased metabolic stress.When combined with aerobic or endurance exercise,it also enhances the expression of angiogenic substances such as vascular endothelial growth factor(VEGF).In addition,hypoxic environments can also promote additional recruitment of type II muscle fibers.Therefore,using the characteristics of blood flow restriction and combining it with traditional training methods should be able to form a deeper training stimulus,thereby improving the training effect and efficiency.MethodsThis paper mainly includes 3 independent intervention experiments,each with a duration of 2weeks.According to the sports team’s annual training plan,they were arranged in different training stages and times,and the effects of blood flow restriction training on maximal muscle strength,muscle performance and strength development rate were verified in turn.6-9 Winter Paralympic alpine skiers in standing class participated in the intervention experiment.The grouping method was to use the lower limb on the dominant side as the control side and the other side as the experimental side.In the study of the effect of blood flow restriction on the maximal muscle strength,athletes first performed 75% 1RM high-intensity strength training,and then performed 4sets of 30% 1RM blood flow restriction exercises under the condition of experimental side blood flow restriction.4 times a week,and compared the changes of maximum torque and muscle fiber recruitment ability before and after the 2-week intervention.In a study of the effects of blood flow restriction on the strength and endurance,athletes completed four weekly sessions of muscular endurance and aerobic training under the condition of blood flow restriction on the experimental side.,and compared the changes of muscle work ability and blood perfusion before and after the2-week intervention.In the study of the effect of blood flow restriction on the explosive force,athletes completed plyometrics 4 times a week under the condition of blood flow restriction on the experimental side,and compared the changes in indicators such as rate of force development(RFD)before and after the 2-week intervention.Results1.Only the absolute and relative value of the maximum torque in knee joint extensors on the experimental side were significantly increased(P<0.01);there were no significant differences in the SEMG(surface electromyography)change rate of the vastus medialis and vastus lateralis between the experimental side and the control side,and only the SEMG change rate of the rectus femoris changed significantly.2.BFR increased significantly absolute and relative the total amount of work(P<0.01)and maximal work(P < 0.05),and the blood perfusion volume(P<0.05)and the blood perfusion volume change rate(P<0.01)were significantly increased by blood flow restriction.3.Only the RFD of experimental side knee extensor was significantly increased,and the absolute RFD in the 20-200 ms time interval was significantly increased(20-120 ms,P<0.05;120-200 ms,P<0.01),in 120-200 ms time interval the relative RFD increased significantly(P<0.05).Conclusions1.As a supplement to maximal muscle strength exercise,2 weeks of combined blood flow restriction training and high-intensity strength training significantly improved the maximum torque of Winter Paralympic alpine skiers,indicating that this intervention is more conducive to the growth of muscle strength.2.Through the 2-week training intervention,the combination of blood flow restriction with local muscle endurance and aerobic training significantly improved the work ability,peak work and blood perfusion volume in the Winter Paralympic alpine skiers,indicating that the intervention program is more conducive to the growth of strength endurance.3.Through a 2-week training intervention,the combination of blood flow restriction and plyometrics significantly improved the rate of force development in the Winter Paralympic alpine skiers in the early stage of muscle contraction(≤200ms),indicating that the intervention program is more conducive to the increase of explosive force. |
