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Ricardo J.S. Costa, Robert Walters, James L.J. Bilzon and Neil P. Walsh

The purpose of the study was to determine the effects of carbohydrate (CHO) intake, with and without protein (PRO), immediately after prolonged strenuous exercise on circulating bacterially stimulated neutrophil degranulation. Twelve male runners completed 3 feeding interventions, 1 week apart, in randomized order after 2 hr of running at 75% VO2max. The feeding interventions included a placebo solution, a CHO solution equal to 1.2 g CHO~/kg body mass (BM), and a CHO-PRO solution equal to 1.2 g CHO/kg BM and 0.4 g PRO/kg BM (CHO+PRO) immediately postexercise. All solutions were flavor and water-volume equivalent (12 ml/kg BM). Circulating leukocyte counts, bacterially stimulated neutrophil degranulation, plasma insulin, and cortisol were determined from blood samples collected preexercise, immediately postexercise, and every 30 min until 180 min postexercise. The immediate postexercise circulating leukocytosis, neutrophilia, and lymphocytosis (p < .01 vs. preexercise) and the delayed lymphopenia (90 min postexercise, p < .05 vs. preexercise) were similar on all trials. Bacterially stimulated neutrophil degranulation decreased during recovery in control (23% at 180 min, p < .01 vs. preexercise) but remained above preexercise levels with CHO and CHO+PRO. In conclusion, CHO ingestion, with or without PRO, immediately after prolonged strenuous exercise prevented the decrease in bacterially stimulated neutrophil degranulation during recovery.

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Dylan Thompson, Clyde Williams, Stephen J. McGregor, Ceri W. Nicholas, Frank McArdle, Malcolm J. Jackson and Jonathan R. Powell

The aim of the present study was to investigate whether 2 weeks of vitamin C supplementation affects recovery from an unaccustomed bout of exercise. Sixteen male subjects were allocated to either a placebo (P; n = 8) or vitamin C group (VC; n = 8). The VC group consumed 200 mg of ascorbic acid twice a day, whereas the P group consumed identical capsules containing 200 mg of lactose. Subjects performed a prolonged (90-min) intermittent shuttle-running test 14 days after supplementation began. Post-exercise serum creatine kinase activities and myoglobin concentrations were unaffected by supplementation. However, vitamin C supplementation had modest beneficial effects on muscle soreness, muscle function, and plasma concentrations of malondialdehyde. Furthermore, although plasma interleukin-6 increased immediately after exercise in both groups, values in the VC group were lower than in the P group 2 hours after exercise (p < .05). These results suggest that prolonged vitamin C supplementation has some modest beneficial effects on recovery from unaccustomed exercise.

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Rennae Williams Stowe

This review presents a framework for understanding the role of social support in athletic injury prevention and recovery. The stress-injury model is presented, which is the theoretical basis for many studies on psychosocial factors related to injury in sport. In addition, we discuss the definition of social support, types and sources of social support for the athlete, and strategies supporting others can use to show their support. Finally, using social support as a rehabilitation strategy and gender differences will be presented.

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C. Martyn Beaven, Christian Cook, David Gray, Paul Downes, Ian Murphy, Scott Drawer, John R. Ingram, Liam P. Kilduff and Nicholas Gill

Rugby preseason training involves high-volume strength and conditioning training, necessitating effective management of the recovery-stress state to avoid overtraining and maximize adaptive gains.

Purpose:

Compression garments and an electrostimulation device have been proposed to improve recovery by increasing venous blood flow. These devices were assessed using salivary testosterone and cortisol, plasma creatine kinase, and player questionnaires to determine sleep quality, energy level, mood, and enthusiasm.

Methods:

Twenty-five professional rugby players were assigned to 1 of 2 treatments (compression garment or a concurrent combination of electrostimulation and compression) in a crossover design over 2 × 2-wk training blocks.

Results:

Substantial benefits were observed in self-assessed energy levels (effect size [ES] 0.86), and enthusiasm (ES 0.80) as a result of the combined treatment when compared with compression-garment use. The combination treatment had no discernable effect on salivary hormones, with no treatment effect observed. The electrostimulation device did tend to accelerate the return of creatine kinase to baseline levels after 2 preseason rugby games when compared with the compression-garment intervention (ES 0.61; P = .08).

Conclusions:

Electrostimulation elicited psychometric and physiological benefits reflective of an improved recovery-stress state in professional male rugby players when combined with a lower-body compression garment.

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James A. Betts, Keith A. Stokes, Rebecca J. Toone and Clyde Williams

Endocrine responses to repeated exercise have barely been investigated, and no data are available regarding the mediating influence of nutrition. On 3 occasions, participants ran for 90 min at 70% VO2max (R1) before a second exhaustive treadmill run at the same intensity (R2; 91.6 ± 17.9 min). During the intervening 4-hr recovery, participants ingested either 0.8 g sucrose · kg−1 · hr−1 with 0.3 g · kg−1 · hr−1 whey-protein isolate (CHO-PRO), 0.8 g sucrose · kg−1 · hr−1 (CHO), or 1.1 g sucrose · kg−1 · hr−1 (CHO-CHO). The latter 2 solutions therefore matched the former for carbohydrate or for available energy, respectively. Serum growth-hormone concentrations increased from 2 ± 1 μg/L to 17 ± 8 μg/L during R1 considered across all treatments (M ± SD; p ≤ .01). Concentrations were similar immediately after R2 irrespective of whether CHO or CHO-CHO was ingested (19 ± 4 μg/L and 19 ± 5 μg/L, respectively), whereas ingestion of CHO-PRO produced an augmented response (31 ± 4 μg/L; p ≤ .05). Growth-hormone-binding protein concentrations were unaffected by R1 but increased similarly across all treatments during R2 (from 414 ± 202 pmol/L to 577 ± 167 pmol/L; p ≤ .01), as was the case for plasma total testosterone (from 9.3 ± 3.3 nmol/L to 14.7 ± 4.6 nmol/L; p ≤ .01). There was an overall treatment effect for serum cortisol (p ≤ .05), with no specific differences at any given time point but lower concentrations immediately after R2 with CHO-PRO (608 ± 133 nmol/L) than with CHO (796 ± 278 nmol/L) or CHO-CHO (838 ± 134 nmol/L). Ingesting carbohydrate with added whey-protein isolate during short-term recovery from 90 min of treadmill running increases the growth-hormone response to a second exhaustive exercise bout of similar duration.

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Anthea C. Clarke, Judith M. Anson and David B. Pyne

Purpose:

To examine relationships between on-field game movement patterns and changes in markers of neuromuscular fatigue and muscle damage during a 2-d women’s rugby sevens tournament.

Methods:

Female national (mean ± SD n = 12, 22.3 ± 2.5 y, 1.67 ± 0.04 m, 65.8 ± 4.6 kg) and state (n = 10, 24.4 ± 4.3 y, 1.67 ± 0.03 m, 66.1 ± 7.9 kg) representative players completed baseline testing for lower-body neuromuscular function (countermovement-jump [CMJ] test), muscle damage (capillary creatine kinase [CK]), perceived soreness, and perceived recovery. Testing was repeated after games on days 1 and 2 of the tournament. GPS (5-Hz) data were collected throughout the tournament (4−6 games/player).

Results:

National players were involved in greater on-field movements for total time, distance, high-speed running (>5 m/s), and impacts >10 g (effect size [ES] = 0.55−0.97) and displayed a smaller decrement in performance from day 1 to day 2. Despite this, state players had a much greater 4-fold increase (ΔCK = 737 U/L) in CK compared with the 2-fold increase (ΔCK = 502 U/L) in national players (ES = 0.73). Both groups had similar perceived soreness and recovery while CMJ performance was unchanged. High-speed running and impacts >10 g were largely correlated (r = .66−.91) with ΔCK for both groups.

Conclusion:

A 2-day women’s rugby sevens tournament elicits substantial muscle damage; however, there was little change in lower-body neuromuscular function. Modest increases in CK can largely be attributed to high-speed running and impacts >10 g that players typically endure.

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Ida A. Heikura, Trent Stellingwerff, Antti A. Mero, Arja Leena Tuulia Uusitalo and Louise M. Burke

Contemporary nutrition guidelines promote a variety of periodized and time-sensitive recommendations, but current information regarding the knowledge and practice of these strategies among world-class athletes is limited. The aim of this study was to investigate this theme by implementing a questionnaire on dietary periodization practices in national/international level female (n = 27) and male (n = 21) middle- and long-distance runners/race-walkers. The questionnaire aimed to gain information on between and within-day dietary choices, as well as timing of pre- and posttraining meals and practices of training with low or high carbohydrate (CHO) availability. Data are shown as percentage (%) of all athletes, with differences in responses between subgroups (sex or event) shown as Chi-square x2 when p < .05. Nearly two-thirds of all athletes reported that they aim to eat more food on, or after, hard training days. Most athletes said they focus on adequate fueling (96%) and adequate CHO and protein (PRO) recovery (87%) around key sessions. Twenty-six percent of athletes (11% of middle vs 42% of long-distance athletes [x 2 (1, n = 46) = 4.308, p = .038, phi = 0.3])) reported to undertake training in the fasted state, while 11% said they periodically restrict CHO intake, with 30% ingesting CHO during training sessions. Our findings show that elite endurance athletes appear to execute pre- and post-key session nutrition recovery recommendations. However, very few athletes deliberately undertake some contemporary dietary periodization approaches, such as training in the fasted state or periodically restricting CHO intake. This study suggests mismatches between athlete practice and current and developing sports nutrition guidelines.

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Ricardo J.S Costa, Samuel J. Oliver, Stewart J. Laing, Robert Walters, James L.J Bilzon and Neil P. Walsh

The aim of the study was to determine the influence of immediate and 1-hr-delayed carbohydrate (CHO) and protein (PRO) feeding after prolonged exercise on leukocyte trafficking, bacterially stimulated neutrophil degranulation, saliva secretory IgA (S-IgA) responses, and circulating stress hormones. In randomized order, separated by 1 wk, 9 male runners completed 3 feeding interventions after 2 hr of running at 75% VO2max. During control (CON), participants received water (12 ml/kg body mass [BM]) immediately and 1 hr postexercise. During immediate feeding (IF), participants received a CHO-PRO solution equal to 1.2 g CHO/kg BM and 0.4 g PRO/kg BM immediately postexercise and water 1 hr postexercise. During delayed feeding (DF), participants received water immediately postexercise and CHO-PRO solution 1 hr postexercise. Unstimulated saliva and venous blood samples were collected preexercise, immediately postexercise, and every 20 min until 140 min postexercise. No significant interactions were observed for circulating leukocytes and T-lymphocyte subset counts, S-IgA secretion rate, or plasma cortisol, epinephrine, or norepinephrine concentration. Bacterially stimulated neutrophil degranulation decreased during recovery on CON and DF (24% and 31%, respectively, at 140 min; p < .01) but not on IF. Compared with CON, neutrophil degranulation was higher on IF at 100 min postexercise and higher on IF than DF at 80 min and 100 min onward postexercise (p < .05). Ingestion of a CHO-PRO solution immediately after, but not 1 hr after, prolonged strenuous exercise prevented the decrease in neutrophil degranulation but did not alter circulating stress hormone, leukocyte trafficking, or S-IgA responses. Further research should identify the independent effect of different quantities of CHO and PRO ingestion during recovery on neutrophil responses and other aspects of immune function.

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Shona L. Halson

An increase in research investigating recovery strategies has occurred alongside the increase in usage of recovery by elite athletes. Because there is inconsistent evidence regarding the benefits of recovery on performance, it is necessary to examine research design to identify possible strategies that enhance performance in different athlete settings. The purpose of this review is to examine available recovery literature specifically related to the time frame between performance assessments to identify considerations for both research design and practical use of recovery techniques.

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Kelly A. Brock, Lindsey E. Eberman, Richard H. Laird IV, David J. Elmer and Kenneth E. Games

recover from muscle damage. Several treatments have been proposed for EIMD and DOMS and have been investigated for their efficacy in alleviating soreness and improving performance as measured by reduced recovery times. Such treatments include massage, 2 , 4 – 7 compression garments, 1 , 4 , 5 , 8 – 10