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The aim was to investigate the effects of low-load resistant training combined with vascular occlusion or normobaric hypoxic exposure, on neuromuscular function. In a randomised controlled trial, well-trained athletes took part in a 5-week training of knee flexor/extensor muscles in which low-load resistant exercise (20% of one repetition maximum, 1-RM) was combined with either (1) an occlusion pressure of approximately 230 mmHg (KT, n = 10), (2) hypoxic air to generate an arterial blood oxygen saturation of ~80% (HT, n = 10), or (3) with no additional stimulus (CT, n = 10). Before and after training, participants completed the following tests: 3-s maximal voluntary contraction (MVC₃), 30-s MVC, and an endurance test (maximal number of repetitions at 20% 1-RM, Reps₂₀). Electromyographic activity (root mean square, RMS) was measured during tests and the cross-sectional area (CSA) of the quadriceps and hamstrings was measured pre- and post-training. Relative to CT, KT, and HT showed likely increases in MVC₃ (11.0 ± 11.9 and 15.0 ± 13.1%, mean ± 90% confidence interval), MVC₃₀ (10.2 ± 9.0 and 18.3 ± 17.4%), and Reps₂₀ (28.9 ± 23.7 and 23.3 ± 24.0%). Compared to the CT group, CSA increased in the KT (7.6 ± 5.8) and HT groups (5.3 ± 3.0). KT had a large effect on RMS during MVC₃, compared to CT (effect size 0.8) and HT (effect size 0.8). We suspect hypoxic conditions created within the muscles during vascular occlusion and hypoxic training may play a key role in these performance enhancements.

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Background: Whole body vibration (WBV) training is a regime of training on a vibration platform that provides oscillatory movement to the body. Vibration training may be a potentially useful therapeutic strategy to control diabetes and its complications. This study aimed to evaluate the effect of WBV on glycemic indices and peripheral blood flow in type II diabetic patients.Methods: A parallel group clinical trial was conducted with 1:1 allocation ratio at Khon Kaen University between February and May 2010. The study included diabetic patients receiving diet or oral medication control over the previous year and excluded patients with serious medical and musculoskeletal disorders. Forty type II diabetic patients [14 males, 26 females, 63.2 (7.7) y, mean (SD)] were randomised into two groups (WBV and control) by computer software using a block of four design. The WBV group was given two sets of six one-minute vibration squats, three times per week for twelve weeks. The control group maintained their normal physical activity levels. The primary outcome was the patients glycemic indices.Results: We found no significant difference in glycosylated haemoglobin (HbA1c), fasting blood sugar, insulin level and insulin sensitivity between WBV and control groups. Compared to the control group, WBV training resulted in a substantial reduction in resting diastolic blood pressure -7.1 mmHg (95% CI: -10.9, -3.3, P = 0.001) and peak systolic velocity -7.3 cm.sec -1 (95% CI: -14.7, -0.03, P = 0.049), but made little difference to resting heart rate, systolic blood pressure, end diastolic velocity, and popliteal artery diameter.Conclusion: Whole body vibration improved resting diastolic blood pressure and peak systolic velocity, however, any beneficial effect of WBV on glycemic indices remains unclear.

The purpose of this study was to compare the effect of elastic tape (Kinesio tape) to placebo tape or static stretching on delayed onset muscle soreness. Fifty-one untrained female healthy volunteers were randomly assigned into three groups (n = 17/group), elastic tape, placebo tape and stretching group. Muscle soreness was induced by 4 sets of 25 maximal isokinetic (60°.s) eccentric contractions of dominant quadriceps on an isokinetic dynamometer. Compared with placebo tape, the elastic tape participants had less muscle soreness at 72 h post-exercise (p = 0.01). The elastic tape also increased isometric strength at 72 h post-exercise compared with the placebo (p = 0.03) and stretching group (p = 0.02). However, there was little effect between groups for changes in thigh circumference, jumping, pressure pain threshold, rate of perceived exertion, creatine kinase activity and joint motion. Elastic taping increased muscle strength recovery and reduced muscle soreness after intensive exercise.

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Short-term exercise training in humans attenuates AMP-activated protein kinase (AMPK) activation during subsequent exercise conducted at the same absolute workload. Short-term 5-aminoimidazole-4-carboxyamide-ribonucleoside (AICAR) administration in rats mimics exercise training on skeletal muscle in terms of increasing insulin sensitivity, mitochondrial enzymes, and GLUT4 content, but it is not known whether these adaptations are accompanied by reduced AMPK activation during subsequent exercise. We compared the effect of 10 days of treadmill training (60 min/day) with 10 days of AICAR administration (0.5 mg/g body weight ip) on subsequent AMPK activation during 45 min of treadmill exercise in male Sprague-Dawley rats. Compared with nonexercised control rats, acute exercise significantly (P < 0.05) increased AMPKalpha Thr172 phosphorylation (p-AMPKalpha; 1.6-fold) and ACCbeta Ser218 phosphorylation (p-ACCbeta; 4.9-fold) in the soleus and p-ACCbeta 2.2-fold in the extensor digitorum longus. Ten days of exercise training abolished the increase in soleus p-AMPKalpha and attenuated the increase in p-ACCbeta (nonsignificant 2-fold increase). Ten days of AICAR administration also attenuated the exercise-induced increases in AMPK signaling in the soleus although not as effectively as 10 days of exercise training (nonsignificant 1.3-fold increase in p-AMPKalpha; significant 3-fold increase in p-ACCbeta). The increase in skeletal muscle 2-deoxyglucose uptake during exercise was greater after either 10 days of exercise training or AICAR administration. In conclusion, 10 days of AICAR administration substantially mimics the effect of 10 days training on attenuating skeletal muscle AMPK activation in response to subsequent exercise.

Whole body vibration (WBV) is widely promoted as a means of improving muscle strength, but the evidence of a performance benefit is unclear with some reporting improvements and others finding none. The objective of this study was to analyze the current evidence for the effectiveness of WBV on jump height. We included randomized controlled trials or matched design studies comparing the effect of WBV training on countermovement and squat jump (SJ) height, which were gathered from MEDLINE, Web of Knowledge, Sciencedirect, Proquest, Scopus, Google Scholar, and SPORTDiscus databases. The overall effect of WBV training (from the 15 studies included) compared with having no additional exercise on countermovement jump height yielded a positive standardized mean difference of 0.77 (95% confidence interval, 0.55-0.99). The effect of WBV training on SJ height was 0.68 (0.08-1.11). Vibration exercise consisting of a higher frequency (>30 Hz, 0.86, 0.62-1.10), higher amplitude (>3 mm, 0.84, 0.52-1.17), longer exposure duration (>10 minutes per session, 0.92, 0.48-1.36), longer training period (>12 weeks, 0.87, 0.56-1.19) and among nonathletes (0.96, 0.63-1.30) had greater benefit for jump height improvement than a lower frequency (≤ 30 Hz, 0.56, 0.13-0.99), lower amplitude (≤ 3 mm, 0.66, 0.35-0.98), shorter exposure duration (≤ 10 minutes per session, 0.68, 0.45-0.92), intermediate training period (4-12 weeks, 0.72, 0.35-1.09), shorter training period (<4 weeks, 0.58, -0.08 to -1.23) and in athletes (0.59, 0.31-0.88). The effect of WBV training compared with a standard cardiovascular-type exercise group from 4 studies was 0.63 (0.10-1.15). In conclusion, WBV training produces a moderate-to-large effect on jump height. Vibration training protocols with higher frequencies, higher amplitudes, longer exposures per session, and longer training periods are more likely to enhance muscle power.