ABSTRACT
Objective:To explore the correlation between sarcopenia and balance in old women. Methods:From September to November, 2017, 224 women aged 60 to 70 were recruited. They were divided into normal group (n = 198) and sarcopenia group (n = 26) according to the results of muscle volume, grip strength and 6-meter walking speed (6MWS), and tested with single foot standing with eyes close (SSEC) and the five times of sit-to-stand (5STS). The correlation of the time of SSEC and 5STS to muscle volume, grip strength and 6MWS were analyzed with Pearson's Correlation Analysis in both groups, respectively. Results:The incidence of simple decrease in muscle volume, grip strength and 6MWS was 20.5%, 14.3% and 2.2%, respectively, and the incidence of sarcopenia was 11.6%. The time of SSEC was shorter in the sarcopenia group than in the normal group (t = 4.072, P < 0.001), and the time of 5STS was longer (t = -5.461, P < 0.001). The time of SSEC correlated with 6MWS in normal group (r = 0.675, P < 0.01), and it correlated with 6MWS (r = 0.492) and grip strength (r = 0.286) in the sarcopenia group (P < 0.001). The time of 5STS correlated with muscle volume (r = 0.258, r = 0.321), grip strength (r = 0.351, r = 0.462) and 6MWS (r = 0.337, r = 0.396) in both groups (P < 0.001). Conclusion:Compared with muscle mass and strength, the muscle activities remain well in the old women in the process of aging. Both static and dynamic balance reduce in the old women with sarcopenia. The static balance mainly relates with muscle activities, while the dynamic balance relates with all the muscle mass, strength and activities.
ABSTRACT
Objective：To investigate the relationship between clinical assessment of pain and muscle activity during walking in patients with severe knee osteoarthritis (OA)．Methods：Eleven patients diagnosed as having severe knee OA (13 knees) were evaluated with electromyography and numerical rating scale (NRS) of pain during walking. Electromyography was recorded from the vastus medialis (VM), semitendinosus (ST), vastus lateralis (VL), and biceps femoris (BF) muscles. Co-contraction indexes (CCIs) for the extensor and flexor muscles of the knee joint were calculated as follows：using the VM and ST data for CCI at the medial aspect of the knee and the VL and BF data for CCI at the lateral aspect. Spearman's rank correlation coefficients between the average individual muscle activities or CCI and pain were calculated.Results：During the terminal stance of walking, NRS significantly correlated with the activation patterns of BF (r ＝－0.61, p＜0.05), the CCI of VL-BF (r ＝－0.582, p＜0.05), and the CCI of VM-ST (r ＝－0.596, p＜0.05)．Conclusion：This study suggests that pain severity is reflected in increasing CCI at the medial and lateral aspects during the terminal stance phase in severe knee OA.
ABSTRACT
This study examined the relationship between riding posture and muscle activities during passive exercise on horseback-riding simulation equipment. The effects of passive training on the prototypes were also determined. Three prototypes with tilted seat (A110, A130, and A140) were developed with an attempt to change the angle between trunk and leg to 110, 130, and 140 degrees, respectively. Twelve female aged 42.7±2.3 years performed passive exercise on the three prototypes and isometric maximal voluntary contraction (MVC) tests. Electromyogram of nine muscles in the trunk and lower limb were recorded. On A110, back muscle showed the largest activity (22%MVC ; p<0.01 ; repeated measures ANOVA). Contrastingly on A140, abdominal muscle and knee extensor showed the largest activity (40%MVC and 26%MVC ; p<0.01). Passive training on the prototypes for 30 minutes/day, 4 times/week, 8 weeks produced enhancement of muscle strength in trunk and hip. Riding posture is an effective factor to control physical effects without increasing the velocity on horseback-riding simulation equipment.