Background/Objective: The aim of this study was to determine whether unilateral manual needling at nonacupoints could result in bilateral strength gain similar to that found in electroacupuncture at specific acupoints.Methods: Fifty healthy male volunteers with an age range of 19-27 years were recruited and randomly allocated into five groups: (1) manual acupuncture and (2) electroacupuncture at two acupoints (ST-36 and ST-39); (3) manual acupuncture and (4) electroacupuncture at two nonacupoints on the tibialis anterior muscle; and (5) control group. The intervention groups received needling in each session on the right leg for 15 minutes in Week 1, 20 minutes in Week 2, and 30 minutes in Weeks 3-8, three sessions per week. The maximal isometric ankle dorsiflexion strength and muscle activation (as determined by twitch interpolation) of both legs were assessed pre, post, 2 weeks post, and 3 weeks post the experimental period.Results: Mixed models (linear) with repeated-measures analysis identified significant strength gains (p < 0.01) after the intervention period in both limbs, while no significant differences were detected between the intervention groups and between the two legs, and no change was found in the control group. A significant improvement in muscle activation (p < 0.01) was also observed in both legs in the intervention groups.Conclusion: It was concluded that both unilateral manual and electric needling caused significant bilateral strength gain, and this effect was not specific to the selected acupoints or electric stimulation. The strength gain was sustained for at least 3 weeks after the 8-week intervention. Copyright (C) 2015, The Society of Chinese Scholars on Exercise Physiology and Fitness. Published by Elsevier (Singapore) Pte Ltd. All rights reserved.

Objective to determine whether voluntary activation of quadriceps femoris is impaired at the later recovery phase of chronic knee injuries. Methods Volunteer participants were recruited from the student population of Tianjin University of Sport. Thirty participants with knee injuries and 30 healthy participants participated in the study. Muscle strength in maximum voluntary contraction (MVC), muscle activation (MA), and the rate of force development (RFD) in isometric knee extension were assessed for both legs using a custom-built dynamometer. Independent Samples T test was used to compare the mean values between the two groups or legs. Results No significance differences were found in the measured variables between the two legs in the healthy comparison group. The MVC and RFD of the right leg in the comparison group were lower than that of the uninjured side in the injuries group (P<0.05, P<0.01). The MA and RFD of the injured side in the injuries group were lower than that of the uninjured side (P<0.05, P<0.01). Conclusion Although the strength was recovered back to the level of the uninjured side, the voluntary activation of quadriceps femoris was still impaired during the later stage of knee injuries which indicated that the neuromuscular control of the knee extensors was not fully recovered and this might be one of the major factors affecting the functional status of the patients. The twitch interpolation method for determining voluntary activities was sensitive to the functional changes in knee extensor.