Nuttaset Manimmanakorn

Effects of low-load resistance training combined with blood flow restriction or hypoxia on muscle function and performance in netball athletes

OBJECTIVES To investigate the effect of blood flow restriction or normobaric hypoxic exposure combined with low-load resistant exercise (LRE), on muscular strength and endurance. DESIGN A randomised controlled trial. METHODS Well-trained netball players (n=30) took part in a 5 weeks training of knee flexor and extensor muscles in which LRE (20% of one repetition maximum) was combined with (1) an occlusion pressure of approximately 230mmHg around the upper thigh (KT, n=10), (2) hypoxic air to generate blood oxyhaemoglobin levels of approximately 80% (HT, n=10) or (3) with no additional stimulus (CT, n=10). The training was of the same intensity and amount in all groups. One to five days before and after training, participants performed a series of strength and endurance tests of the lower limbs (3-s maximal voluntary contraction [MVC3], area under 30-s force curve [MVC30], number of repetitions at 20% 1RM [Reps201RM]). In addition, the cross-sectional area (CSA) of the quadriceps and hamstrings were measured. RESULTS Relative to CT, KT and HT increased MVC3 (11.0±11.9% and 15.0±13.1%), MVC30 (10.2±9.0% and 18.3±17.4%) and Reps201RM (28.9±23.7% and 23.3±24.0%, mean±90% confidence interval) after training. CSA increased by 6.6±4.5%, 6.1±5.1% and 2.9±2.7% in the KT, HT and CT groups respectively. CONCLUSIONS LRE in conjunction with KT or HT can provide substantial improvements in muscle strength and endurance and may be useful alternatives to traditional training practices.

Long-term effect of whole body vibration training on jump height: meta-analysis.

Abstract Manimmanakorn, N, Hamlin, MJ, Ross, JJ, and Manimmanakorn, A. Long-term effect of whole body vibration training on jump height: meta-analysis. J Strength Cond Res 28(6): 1739–1750, 2014—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.

Effects of elastic taping, non-elastic taping and static stretching on recovery after intensive eccentric exercise

ABSTRACT 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−1) 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.

Effects of Zingiber cassumunar (Plai cream) in the treatment of delayed onset muscle soreness

OBJECTIVE To evaluate the effects of Zingiber cassumunar (Plai cream) in either 7% or 14% concentration on delayed onset muscle soreness (DOMS). METHODS Seventy-five untrained healthy volunteers (28 males and 47 females), performed 4 sets of 25 eccentric repetitions of the dominant quadriceps muscle on an isokinetic dynamometry machine. Participants were then randomized into 3 groups: 14% Plai cream, 7% Plai cream and placebo cream. Two grams of the cream (strips of 5-cm long) were gently rubbed into the quadriceps muscles for 5 min immediately following the exercise and every 8 h thereafter for 7 d in all groups. Muscle soreness, muscle strength, jump height, thigh circumference and creatine kinase were measured before and after eccentric exercise. RESULTS Compared to the placebo cream the 14% Plai cream substantially reduced muscle soreness over the 7 d by -82% (95% CI = -155% to -6%, P = 0.03), but had similar muscle soreness effects to 7% Plai cream (-34%, -96% to 27%, P = 0.2). Compared to the placebo cream the 7% Plai cream resulted in a small non-significant reduction in muscle soreness levels over the following 7 d (-40%, -116% to 36%, P = 0.3). Compared to placebo cream there was little effect of Plai cream (7% or 14%) on muscle strength, jump height, thigh circumference or creatine kinase concentration. CONCLUSION Using 14% Plai cream over a 7-day period substantially reduced muscle soreness symptoms compared to 7% Plai cream or a placebo cream. The authors suggest that the administration of 14% Plai cream is a useful alternative in the management of DOMS. TRIAL REGISTRATION Thai Clinical Trial Registry TCTR20140215001.

Live high-train low altitude training: responders and non-responders

Live High-Train Low Altitude Training: Responders and Non-Responders Objective: Investigate differences between athletes that responded (improved performance) compared to those that did not, after a 20- day “live high-train low” (LHTL) altitude training camp. Methods: Ten elite triathletes completed 20 days of live high (1545-1650 m), train low (300 m) training. The athletes underwent (i), two 800-m swimming time trials at sea-level (1 week prior to and 1 week after the altitude camp) and (ii) two 10-min standardised submaximal cycling tests at altitude on day 1 and day 20 of the altitude camp. Acute mountain sickness (AMS) was also measured during the camp. Based on their 800-m swimming time trial performances, athletes were divided into responders (improved by 3.2 ± 2.2%, mean ± SD, n=6) and non-responders (decreased by 1.8 ± 1.2%, n=4). Results: Compared to non-responders, the responders had lower exercise heart rates (-6.3 ± 7.8%, mean ± 90% CL, and higher oxygen saturations (1.2 ± 1.3%) at the end of the 10-min submaximal test after the camp. Compared to the responders, the non-responders had substantially higher VE and VE/VO2 during the submaximal test on day 1 of the altitude training camp, and a substantially higher RER during the submaximal test on day 20 of the camp. As a result of the altitude training, exercise economy of the non-responders compared to the responders deteriorated (i.e., non-responders required more oxygen per watt). Non-responders were 3.0 times (90% CL=0.5-16.6) more likely to suffer symptoms of acute mountain sickness during first 5 days of altitude compared to responders. Conclusion: Changes in SpO2, heart rate and some respiratory variables during exercise and resting AMS scores may help determine athletes that respond to LHTL altitude training camps from athletes that fail to respond to such training.

Effects of whole body vibration on glycemic indices and peripheral blood flow in type II diabetic patients

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.

Effect of Whole-Body Vibration Therapy on Performance Recovery

PURPOSE To compare whole-body vibration (WBV) with traditional recovery protocols after a high-intensity training bout. METHODS In a randomized crossover study, 16 athletes performed 6 × 30-s Wingate sprints before completing either an active recovery (10 min of cycling and stretching) or WBV for 10 min in a series of exercises on a vibration platform. Muscle hemodynamics (assessed via near-infrared spectroscopy) were measured before and during exercise and into the 10-min recovery period. Blood lactate concentration, vertical jump, quadriceps strength, flexibility, rating of perceived exertion (RPE), muscle soreness, and performance during a single 30-s Wingate test were assessed at baseline and 30 and 60 min postexercise. A subset of participants (n = 6) completed a 3rd identical trial (1 wk later) using a passive 10-min recovery period (sitting). RESULTS There were no clear effects between the recovery protocols for blood lactate concentration, quadriceps strength, jump height, flexibility, RPE, muscle soreness, or single Wingate performance across all measured recovery time points. However, the WBV recovery protocol substantially increased the tissue-oxygenation index compared with the active (11.2% ± 2.4% [mean ± 95% CI], effect size [ES] = 3.1, and -7.3% ± 4.1%, ES = -2.1 for the 10 min postexercise and postrecovery, respectively) and passive recovery conditions (4.1% ± 2.2%, ES = 1.3, 10 min postexercise only). CONCLUSION Although WBV during recovery increased muscle oxygenation, it had little effect in improving subsequent performance compared with a normal active recovery.