Effects Of Respiration Modes On Biomechanics During Feed-forward Of The Different Altitude Drop Jumps

Objective:Healthy subjects were instructed to breathe in several different ways,performed drop jumps of different heights in sequence after each breathing mode intervention,and collected biomechanical characteristics of the feed forward control stages of each drop jump movement.The effects of breathing modes and differences in biomechanical characteristics during feedforward of the different altitude drop jumps after intervention with different breathing styles were studied.The improvement of athletic ability.basis of experiments and theoretical support were explored.Method:In this study,15 healthy adult men were selected as experimental subjects to perform three 15-minute breathing interventions.After each breathing intervention,three platform height jumping exercises were completed,and the three platform heights were 15cm,30m,45cm,Vicon infrared high-speed camera system,surface electromyography tester,Swiss Kistler three-dimensional force plate were used to collect data on the biomechanical characteristics of the three height drop jumps during feedforward control stages after intervention of various breathing methods.The biomechanical characteristics such as kinematics,muscle activation pattern,and muscle activation timing index of different height drop jumps during feed-forward stages were analyzed.Two-factor repeated measurement analysis of variance was used to compare the differences in biomechanical characteristics of feedforward control stages at three jump depths after intervention with different breathing patterns.The three breathing methods were(1)Calm breathing:the subjects stood naturally,looked ahead,and breathed naturally for 15 minutes in a quiet state.(2)Deep breathing:The subjects performed deep breathing adjustment for 15 minutes according to their breathing rhythm.(3)inner-power and One-finger Zen pranayama(pranayama):Adopted the inner-strength one-finger meditation method to adjusted the breath for 15 minutes.Result:(1)In the kinematics data of 100ms before the first landing of the drop jump action,the differences between the left and right ankle joint angles between calm breathing,deep breathing,and pranayama were statistically significant(P<0.05).The differences in hip joint angles between 15cm,30cm,and 45cm height jump movements were statistically significant(P<0.05).The average hip joint angles of the left and right sides decreased with the increase of the jump height.The interaction effects of breathing patterns and different height jump depths had no statistical significance for each index(P>0.05).In the kinematics data of 100ms before the second landing of the drop jumps,the differences between the angles of the left and right knees and ankles between calm breathing,deep breathing,and pranayama were statistically significant(P<0.05).The differences in left hip joint angle between calm breathing,deep breathing,and pranayama were statistically significant(P<0.05).The differences between the left hip,knee,right hip,and ankle joints at 15cm,30cm,and 45cm height jumps were statistically significant(P<0.05).The interaction effects of breathing patterns and different height drop jumps had no statistical significance for each index(P>0.05).(2)The EMG data of 100ms before the first landing of the drop jumps was collected,only the Vastus medialis iEMG had statistically significant differences between calm breathing,deep breathing,and pranayama(P<0.05),Only the iEMG of the lateral head of the gastrocnemius muscle at 15cm,30cm,and 45cm jump heights was statistically significant(P<0.05),The interaction between breathing patterns and different height drop jumps was not statistically significant in each muscle iEMG value(P>0.05).In the EMG data of 100ms before the second landing of the deep jump,only the left erector spinae iEMG had statistically significant differences in calm breathing,deep breathing,and pranayama(P<0.05),Only the differences between the left and right rectus iEMGs at 15 cm,30 cm,and 45 cm height drop jumps were statistically significant(P<0.05),The interaction between breathing patterns and different height drop jumps had no statistical significance for each muscle iEMG(P>0.05).(3)There was no significant difference in the number of muscle activations between calm breathing,deep breathing,and pranayama 100ms before the first and second landings of the drop jumps(P>0.05)The number of muscle activations at 15cm,30cm and 45cm height drop jumps were statistically significant(P<0.05).There was no statistical significance in the number of muscle activations in the interaction between breathing patterns and different height drop jumps(P>0.05).100ms before the first landing,the percentage of muscle activation in the 15cm,30cm,and 45cm height drop jumps by the pranayama method was greater than the percentage of muscle activations in the calm and deep breaths at the same height.100ms before the second touchdown,when the drop jump height was 15cm,the percentage of muscle activation in all subjects was greater than the percentage of muscle activation at the same height in deep breathing and calm breathing.After pranayama intervention,when jumping deep at 30cm height,the activation percentage of each muscle was equal to that of deep breathing at 30cm height,and greater than that of calm breathing at 30cm height.When the jumping intervention was performed at a height of 45 cm,the percentage of muscle activation was greater than the percentage of muscle activation at the same height in deep breathing,and less than the percentage of muscle activation at the same height after calm breathing intervention.Conclusions:(1)Under the influence of different breathing modes and jumping height,during the feedforward control stage of drop jumps,the angle of lower limb joints changed,and the body adopted ankle strategy and hip strategy to complete the task of drop jumps(2)The electromyographic activity of the biceps femoris and lateral femoris,medial femoris,and rectus femoris muscles during feed-forward control phase of the drop jumps after the intervention of pranayama intervention was more balanced.With the increased of the height of the drop jumps,the medial femoral muscle and lateral femoral muscle myoelectric activity increased simultaneously,reducing the risk of anterior cruciate ligament injury.(3)Enhanced muscle pre-activation mode could improve landing technology.Respiratory training will help posture control and sports injury prevention.