Effect Of Weight Lifting Training In Sitting Posture On Surface Electromyography And Dynamic Balance Of Lower Limbs In Elderly Women

Objective: The purpose of this study was to investigate the effects of weight-bearing calf lifting training in sitting posture on dynamic balance ability of elderly women,and to explore the characteristics of changes in lower limb muscle recruitment before and after weight-bearing calf lifting training in sitting posture,so as to provide theoretical basis for developing training programs suitable for lower limb function in elderly women.Methods: A total of 40 elderly female volunteers were recruited and randomly divided into experimental group and blank group,with 20 cases in each group.The blank group performed daily living activities without intervention.The experimental group carried out the sitting posture heel lifting training with 1/4 body weight.The training prescription of the experimental group was 3 groups of calf lifting training on each side,10 in each group,twice a day,2min rest between each group,continuous training for 2 weeks.Before and after 2weeks of training,the subjects used the surface electromyography system to collect the dynamic EMG signals of the lower extremity muscles when they went down the stairs(the test muscle groups included: Gluteus maximus superior tract,gluteus maximus inferior tract,gluteus medius,tensor fascia lata,medial head of quadriceps,lateral head of quadriceps,medial head of gastrocnemius,lateral head of gastrocnemius,soleus,tibialis anterior muscle)were used to test the stable limit fall risk index using balance test and training system.Excel software was used to establish the database and input the data.IBM SPSS 22.0 statistical software was used for analysis.Basic clinical data and experimental detection index data of the two groups of subjects were analyzed.P < 0.05 was considered statistically significant.Results:(1)The baseline clinical data of the experimental group and the blank group were compared and analyzed.The results showed that there were no statistical differences in age,height and weight among all groups(P >0.05).(2)The stable ultimate fall risk index of the experimental group was significantly higher after training than before training(P <0.05),with statistical significance;In the blank group,there was no significant change in the stable limit fall risk index after no intervention(P >0.05).(3)Integrated Electromyogram(IEMG)values of the experimental group before and after training.The IEMG values of bilateral gluteus medius,bilateral gluteus maximus superior bundle,bilateral gluteus maximus inferior bundle,bilateral tensor fascia lata,lateral head of bilateral quadriceps,medial head of bilateral quadriceps,bilateral tibialis anterior muscle,bilateral soleus muscle,lateral head of bilateral gastrocnemius and medial head of bilateral gastrocnemius were significantly increased compared with before training(P <0.05).The IEMG value of each test muscle group had no change after no intervention in blank group(P >0.05).Compared with blank group,IEMG values of experimental group were significantly changed in bilateral gluteus medius,bilateral medial head of quadriceps,bilateral lateral head of quadriceps,bilateral tibialis anterior,bilateral soleus,bilateral lateral head of gastrocnemius and bilateral medial head of gastrocnemius compared with blank group,with statistical difference(P <0.05).(4)Comparison of Root Mean Square(RMS)before and after training in the experimental group.RMS values of left gluteus medius,bilateral gluteus maximus superior bundle,right gluteus maximus inferior bundle,bilateral tensor fascia lata,lateral head of bilateral quadriceps,medial head of right quadriceps,bilateral tibialis anterior muscle,right soleus muscle,lateral head of bilateral gastrocnemius and medial head of bilateral gastrocnemius were significantly higher than before training,with statistical difference(P <0.05).The RMS value of each muscle group in blank group did not change after no intervention(P >0.05),and there was no statistical significance.Compared with the blank group,the RMS values of the right tensor fascia lata muscle,the lateral head of the right quadriceps muscle,the medial head of the right quadriceps muscle,the soleus muscle,the lateral head of the bilateral gastrocnemius muscle and the medial head of the bilateral gastrocnemius muscle in the experimental group were significantly changed compared with the blank group,with statistical difference(P <0.05).(5)Comparison of the Median Frequency(MF)values before and after training in the experimental group,the MF values of the right tibialis anterior muscle,bilateral soleus muscle,lateral head of bilateral gastrocnemius muscle and medial head of bilateral gastrocnemius muscle were significantly higher than before training,with statistical difference(P <0.05);The MF value of each test muscle group in blank group did not change after no intervention(P >0.05),and there was no statistical significance.Compared with blank group,MF values of right gluteus maximus superior tract,bilateral tibialis anterior muscle and bilateral soleus muscle in experimental group had significant changes compared with blank group,with statistical difference(P <0.05).Conclusions:(1)Weight-bearing calf lifting training in sitting posture can significantly improve the recruitment of soleus,gastrocnemius and tibialis anterior muscles,improve muscle contractility and improve fatigue resistance of muscles;(2)Sitting weight-bearing heel lifting training can enable elderly women to activate lower limb gluteus medius,upper and lower gluteus maximus fasciculus,tensor ofascia lata,lateral head of quadriceps,medial head of quadriceps,soleus and inner and lateral head of gastrocnemius when going down stairs,enhance lower limb motor coordination,improve dynamic balance control ability when going down stairs,maintain normal lower limb hip,knee,ankle exercise strategy;(3)Weight-bearing heel lifting training in sitting posture can significantly improve the stable limit fall risk index of elderly women,effectively improve their homeostatic balance ability and reduce their fall risk.In conclusion,the sitting posture weight-bearing heel lifting training can improve the dynamic balance ability of elderly women and improve the coordination of lower limb function when they go down stairs.Safe and non-invasive,sitting weight-bearing heel lifting training can not only be used as a daily exercise prescription for elderly women and deserves to be promoted and applied,but also can be applied in the field of rehabilitation for patients with dynamic balance dysfunction to provide theoretical basis for rehabilitation treatment programs.