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This study investigated the effects of custom-fitted compression garments (CG) worn during recovery over a multi-day training camp in elite judo players (judoka). A single blind, placebo-controlled study was carried out in 11 elite judoka, using a two-way crossover design. Two three-day training camps were completed in CG and placebo conditions in a random order. Changes in performance and physiological markers were compared between conditions. Judoka were assessed before training for (maximal) isometric knee extension and grip strength, countermovement jump performance and bench-press velocity, alongside soreness, limb circumferences, plasma creatine kinase activity (CK) and perceived bruising. Measurements were repeated after 12 h, 36 h and 43 h of training, whereupon judoka rated the effectiveness of each intervention. Knee extension and bench-press performance demonstrated significant familiarization (p < 0.001), and were excluded from subsequent analysis. Jump performance was unaffected by training (p > 0.05). Grip strength declined throughout training (p < 0.001), with peak decrements of - 9.7 % indicating mild muscle damage. Increases in bruising, CK and soreness demonstrated highly variable, if significant (p < 0.001) responses. Although CG were perceived as significantly more effective than placebo for recovery (p = 0.046), no effects were observed for any other outcome (p > 0.05). Compression conferred no statistically significant impact upon recovery markers in elite judoka throughout training. Muscle damage responses were inconsistent in this population. Individual athletes would be advised to monitor habitually-used performance measures while using CG to ascertain whether perceptual benefits translate into enhanced recovery.

A variety of strategies exist to modulate acute physiological responses following resistance exercise aimed at enhancing recovery and/or adaptation processes. To assess the true impact of these strategies, it is important to know the ability of measures to detect meaningful change. We investigated the sensitivity of measures used to quantify acute physiological responses to resistance exercise and constructed a physiological profile to characterise the magnitude of change and time course of this response. Eight males, accustomed to regular resistance exercise, performed experimental sessions during a ‘control week’, void of an exercise stimulus. Participants repeated this sequence of experimental sessions the following week, termed the ‘exercise week’, except they performed a bout of lower-limb resistance exercise following baseline assessments. Assessments were conducted at baseline, 2, 6, 24, 48, 72 and 96 h post-intervention. Based on the signal-to-noise ratio, the most sensitive measures were maximal voluntary isometric contraction, 20m sprint, countermovement jump peak force, rate of force development (100-200ms), muscle soreness, daily analysis of life demands for athletes Part B, limb girth, matrix metalloproteinase-9, interleukin-6, creatine kinase and high sensitivity C-reactive protein with ratios of >1.5. There were clear changes in these measures following resistance exercise, determined via magnitude-based inferences. These findings highlight measures that can detect real changes in acute physiological responses following resistance exercise in trained individuals. Researchers investigating strategies to manipulate acute physiological responses for recovery and/or adaptation can use these measures, as well as recommended sampling points, to be confident that their interventions are making a worthwhile impact.

This investigation determined the efficacy of a tart cherry juice in aiding recovery and reducing muscle damage, inflammation and oxidative stress. Twenty recreational Marathon runners assigned to either consumed cherry juice or placebo for 5 days before, the day of and for 48 h following a Marathon run. Markers of muscle damage (creatine kinase, lactate dehydrogenase, muscle soreness and isometric strength), inflammation [interleukin-6 (IL-6), C-reactive protein (CRP) and uric acid], total antioxidant status (TAS) and oxidative stress [thiobarbituric acid reactive species (TBARS) and protein carbonyls] were examined before and following the race. Isometric strength recovered significantly faster (P=0.024) in the cherry juice group. No other damage indices were significantly different. Inflammation was reduced in the cherry juice group (IL-6, P

Purpose: To determine the relative importance of anthropometric and physiological attributes for performance in the 1000-m, 500-m, and 200-m flatwater kayaking events. Methods: Eighteen competitive male kayakers completed performance trials over the 3 distances and a battery of anthropometric and physiological tests. Results: Performance times (mean ± SD) for 1000 m, 500 m, and 200 m were 262.56 ± 36.44 s, 122.10 ± 5.74 s, and 41.59 ± 2.12 s, respectively. Performance in all 3 events was correlated with a number of physiological parameters; in addition, 500-m and 200-m performance was correlated with upper body dimensions. 1000-m time was predicted by power output at lactate turnpoint expressed as a percentage of maximal aerobic power, work done in a 30-s ergometry test and work done in a 2-min ergometry test (adjusted R2 = 0.71, SEE = 5.72 s); 500-m time was predicted by work done and the fatigue index in a 30-s ergometry test, work done in a 2-min ergometry test, peak isometric and isokinetic function (adjusted R2 = 0.79, SEE = 2.49 s); 200-m time was predicted by chest circumference, humeral breadth, peak power, work done, and the fatigue index in a 30-s ergometry test (adjusted R2 = 0.71, SEE = 0.71 s). Conclusions: A number of physiological variables are correlated with performance in all events. 1000-m, 500-m, and 200-m times were predicted with a standard error of only 2.2%, 2.0%, and 1.7%, respectively.

This study examined the effects of beta-hydroxyl-beta-methylbutyrate (HMB) and alpha-ketoisocaproic acid (KIC) supplementation on signs and symptoms of exercise-induced muscle damage following a single bout of eccentrically biased resistance exercise. Six non-resistance trained male subjects performed an exercise protocol designed to induce muscle damage on two separate occasions, performed on the dominant or non-dominant arm in a counter-balanced crossover design. Subjects were assigned to an HMB/KIC (3 g HMB and 0.3 g alpha-ketoisocaproic acid, daily) or placebo treatment for 14 d prior to exercise in the counter-balanced crossover design. One repetition maximum (1RM), plasma creatine kinase activity (CK), delayed onset muscle soreness (DOMS), limb girth, and range of motion (ROM) were determined pre-exercise, at 1h, 24 h, 48 h, and 72 h post-exercise. DOMS and the percentage changes in 1RM, limb girth, and ROM all changed over the 72 h period (P < 0.05). HMB//IC supplementation attenuated the CK response, the percentage decrement in 1RM, and the percentage increase in limb girth (P < 0.05). In addition, DOMS was reduced at 24 h post-exercise (P < 0.05) in the HMB/KIC treatment. In conclusion, 14 d of HMB and KIC supplementation reduced signs and symptoms of exercise-induced muscle damage in non-resistance trained males following a single bout of eccentrically biased resistance exercise.

This study investigated the effect of differing fluid volumes consumed during exercise, on cycle time-trial (TT) performance conducted under thermoneutral conditions (20 degrees C, 70% RH). Ten minutes after consuming a bolus of 6 ml x kg(-1) body mass (BM) of a 6.4% CHO solution and immediately following a warm-up, 8 male cyclists undertook a 1-h self-paced TT on 4 separate occasions. During a "familiarization" trial, subjects were given three 5-min periods (15-20 min, 30-35 min, and 45-50 min) to consume fluid ad libitum. Thereafter subjects undertook, in random order, trials consuming high (HF), moderate (MF), or low fluid (LF) volumes, where 300, 150, and 40 ml of fluid were consumed at 15, 30, and 45 min of each trial, respectively, and total CHO intake was maintained at 57.6 g. During exercise, power output and heart rate were monitored continuously, whilst stomach fullness was rated every 10 min. Additionally, BM loss and BM loss corrected for fluid intake was calculated during each trial. At 40, 50, and 60 min differences in ratings of stomach fullness were found between trials (LF vs. HF and MF vs. HF). There were however no differences in performance or physiological variables (heart rate or BM loss) between trials. These results indicate that when a pre-exercise CHO bolus is consumed, there is no effect of subsequent consumption of different fluid volumes when trained cyclists undertake a 1-h performance task in a thermoneutral environment.

Concurrent training describes the combination of both endurance and strength stimuli within a coherent paradigm. An attenuation in strength, power, and hypertrophy can result from this model of training, in comparison to that resulting from strength only; a phenomenon termed an ‘interference effect’. Rather than adopt a myopic view of the concurrent training paradigm, whereby the addition of an endurance stimulus is fatal to strength-based training outcomes, it is of interest to better understand the response to a concurrent exercise stimulus and elucidate the response to manipulating training variables. Given this, the objectives of this thesis were to investigate and draw conclusions on the short-term response to a strenuous concurrent stimulus (Chapter 4), in addition to the effect of manipulating the programme variables of exercise sequence (Chapter 5) and endurance exercise intensity (Chapters 6 and 7) on strength and endurance-related outcomes.\ud \ud The findings of this thesis indicate concurrent training stimuli to provide a relatively modest level of muscle damage, potentially owing to the order of the two exercise modes, with this programme variable of intra-session exercise sequence affecting improvements in lower-body dynamic strength during a concurrent training programme. Further, the data do not support the premise of a molecular interference effect amongst an endurance-trained phenotype, nor a role for the variable of endurance exercise intensity to modify the molecular response to concurrent stimuli, regardless of training status, or performance outcomes following a short-term concurrent training programme.\ud \ud With regards to practical applications, while an endurance-resistance exercise order might limit muscle damage, the alternate sequence is beneficial for lower-body strength development. Individuals limited by time, such that they must train concurrently with minimal relief between modes of exercise, should adopt a resistance-endurance exercise order to promote strength adaptation across a training programme. Finally, providing it is work- and duration-matched, endurance exercise intensity can be manipulated without detriment to strength performance, amongst endurance trained athletes.