Kysha Harriell

Comparative Impacts of Tai Chi, Balance Training, and a Specially-Designed Yoga Program on Balance in Older Fallers

OBJECTIVE To compare the effect of a custom-designed yoga program with 2 other balance training programs. DESIGN Randomized controlled trial. SETTING Research laboratory. PARTICIPANTS A group of older adults (N=39; mean age, 74.15 ± 6.99 y) with a history of falling. INTERVENTIONS Three different exercise interventions (Tai Chi, standard balance training, yoga) were given for 12 weeks. MAIN OUTCOME MEASURES Balance performance was examined during pre- and posttest using field tests, including the 8-foot up-and-go test, 1-leg stance, functional reach, and usual and maximal walking speed. The static and dynamic balances were also assessed by postural sway and dynamic posturography, respectively. RESULTS Training produced significant improvements in all field tests (P<.005), but group difference and time × group interaction were not detected. For postural sway, significant decreases in the area of the center of pressure with eyes open (P=.001) and eyes closed (P=.002) were detected after training. For eyes open, maximum medial-lateral velocity significantly decreased for the sample (P=.013). For eyes closed, medial-lateral displacement decreased for Tai Chi (P<.01). For dynamic posturography, significant improvements in overall score (P=.001), time on the test (P=.006), and 2 linear measures in lateral (P=.001) and anterior-posterior (P<.001) directions were seen for the sample. CONCLUSIONS Yoga was as effective as Tai Chi and standard balance training for improving postural stability and may offer an alternative to more traditional programs.

Core muscle function during specific yoga poses

OBJECTIVE To assess the potential use of 11 yoga poses in specific training and rehabilitation programs via examination of the muscle activation patterns in selected trunk and hip muscles. DESIGN Repeated-measures descriptive study. SETTING University laboratory, US. PARTICIPANTS Thirty healthy yoga practitioners with more than 3 months yoga practice experience (mean age±SD, 32.0±12.3 y; 8 M/22 F) participated. INTERVENTIONS Surface electromyographic signals of upper rectus abdominis, lower rectus abdominis, longissimus thoracis, external oblique abdominis and gluteus maximum muscle were recorded in 11 yoga poses: Halfway lift, Forward fold, Downward facing dog, Upward facing dog, High plank, Low plank, Chair, Mountain with arms down, Mountain with arms up, Warrior 1 (both sides). MAIN OUTCOME MEASURES Root mean square values of each muscle during each pose, normalized by the maximal voluntary contraction. RESULTS There were significant main effects of pose (p<.001) and muscle (p<.001), and a significant pose×muscle interaction (p=.001). The post hoc analysis revealed unique patterns for the five muscles of interest for each of the 11 poses (p<.024). CONCLUSIONS Variations in core muscle firing patterns depend on the trunk and pelvic positions during these poses. Training programs can be developed by choosing particular poses to target specific core muscles for addressing low back pain and declines in performance. The High plank, Low plank and Downward facing dog poses are effective for strengthening external oblique abdominis, Chair and Warrior 1 poses for targeting gluteus maximum, and Chair and Halfway lift poses for strengthening longissimus thoracis. And these three muscles could be strengthened by the Upward facing dog pose.

Effect of Whole-Body Periodic Acceleration on Exercise-Induced Muscle Damage After Eccentric Exercise

PURPOSE To examine the effects of whole-body periodic acceleration (pGz) on exercise-induced-muscle-damage (EIMD) -related symptoms induced by unaccustomed eccentric arm exercise. METHODS Seventeen active young men (23.4 ± 4.6 y) made 6 visits to the research facility over a 2-wk period. On day 1, subjects performed a 1-repetition-maximum (1RM) elbow-flexion test and were randomly assigned to the pGz (n = 8) or control group (n = 9). Criterion measurements were taken on day 2, before and immediately after performance of the eccentric-exercise protocol (10 sets, 10 repetitions using 120% 1RM) and after the recovery period. During subsequent sessions (24, 48, 72, and 96 h) these data were collected before pGz or passive recovery. Measurements included isometric strength (maximal voluntary contraction [MVC]), blood markers (creatine kinase, myoglobin, IL-6, TNF-α, TBARS, PGF2α, protein carbonyls, uric acid, and nitrites), soreness, pain, circumference, and range of motion (ROM). RESULTS Significantly higher MVC values were seen for pGz throughout the recovery period. Within-group differences were seen in myoglobin, IL-6, IL-10, protein carbonyls, soreness, pain, circumference, and ROM showing small negative responses and rapid recovery for the pGz condition. CONCLUSION Our results demonstrate that pGz can be an effective tool for the reduction of EIMD and may contribute to the training-adaptation cycle by speeding up the recovery of the body due to its performance-loss-lessening effect.

Acute effects of whole body vibration on balance in persons with and without chronic ankle instability

ABSTRACT Chronic ankle instability (CAI) is a common condition following ankle injury that is associated with compromised balance. Whole body vibration training (WBVT) programmes are linked with improved balance and function in athletic and non-athletic populations and may improve balance in CAI. Twelve healthy and seven CAI participants completed two randomly assigned interventions. Two Power Plate® platforms were attached back to back using a Theraband®. Participants stood on the active plate and inactive plate for WBVT and sham interventions, respectively. Each intervention included vibration of the active plate. Centre of pressure (COP) and the star excursion balance test (SEBT) were measured before and at 3, 15 and 30 min following the interventions. Significant improvements were found in the anterior direction of the SEBT following both interventions in CAI and varying patterns of improvement were observed for COP measurements in all participants. Therefore, WBVT does not appear to acutely improve balance in CAI.