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Laura C. Healy, Nikos Ntoumanis, Jet J.C.S. Veldhuijzen van Zanten and Nicola Paine

This investigation sought to clarify mixed results in the literature exploring coach behaviors, basic psychological needs, goal motivation, and well- and ill-being. Regional-level team sport athletes (N = 241) completed questionnaires on the aforementioned variables at the beginning of the season. A subsample (n = 70) provided saliva samples to assess physical ill-being. At the end of the season, athletes (n = 98) reported their goal motivation and attainment. Structural equation modeling demonstrated that coach behaviors were related to needs satisfaction and thwarting, which were related to autonomous and controlled goal motives respectively. Autonomous motives were related to well- and ill-being; controlled motives were only related to ill-being. Over time, only end-of-season autonomous goal motives were related to goal attainment. The findings provide an insight into how coaches can facilitate optimum goal striving and well-being in their athletes.

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Christine Crooks, Martin L. Cross, Clare Wall and Ajmol Ali

Purpose:

This study investigated the effect of bovine colostrum (BC) on mucosal defense in the respiratory tracts of athletes and a nonexercising control group.

Methods:

An athlete cohort (ATH) of 25 (12 male, 13 female) elite swimmers (age 14–23 yr) and a control cohort (CON) of 28 (9M, 19F) students (age 18–27 yr) were randomly allocated in a double-blind manner to receive either 25 g BC (low-protein colostrum powder) or isocaloric placebo (PL) per day for 10 wk. Postprandial saliva samples were analyzed for immunoglobulins (A, G, and M) and osmolality at baseline, after 4 and 10 wk, and 2 wk postsupplementation. Blood samples were analyzed for immunoglobulins and C-reactive protein at baseline, after 5 and 10 wk, and 2 wk postsupplementation. Dietary intake was assessed by self-recorded dietary records. Upper respiratory tract symptoms (URS) and exercise were also self-recorded daily.

Results:

There was no significant time-related effect of the BC supplement on either saliva or plasma immunoglobulin levels for either cohort. After 4 wk supplementation fewer ATH/BC (25%) than ATH/PL participants (61%) reported URS incidents (p = .062). No significant difference occurred in URS reports in the control group.

Conclusion:

There was no measurable effect on immunoglobulin levels of consuming BC, which is in contrast to effects that have been reported previously in marathon runners, indicating that the effect of BC supplementation is not universal in all groups of athletes. Fewer athletes reported URS (although cause unknown) when consuming BC, which may be advantageous for training.

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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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Ryland Morgans, Adam Owen, Dominic Doran, Barry Drust and James P. Morton

Purpose:

To monitor resting salivary secretory immunoglobulin A (SIgA) levels in international soccer players during the short-term training period that precedes international match play.

Methods:

In a repeated-measure design, saliva samples were obtained from 13 outfield soccer players who participated in the training camps preceding 7 games (5 home and 2 away) of the 2014 FIFA World Cup qualifying campaign. Samples were obtained daily for 4 d preceding each game (and analyzed for SIgA using the IPRO oral-fluid-collection system) at match day minus 1 (MD-1), minus 2 (MD-2), minus 3 (MD-3), and minus 4 (MD-4).

Results:

SIgA displayed a progressive decline (P = .01) during the 4-d training period (MD-4, 365 ± 127 μg/mL; MD-3, 348 ± 154 μg/mL; MD-2, 290 ± 138 μg/mL; MD-1, 256 ± 90 μg/mL) such that MD-1 values were significantly lower (P = .01) than both MD-4 and MD-3. The 95% confidence intervals for the differences between MD-1 and MD-4 were –191 to –26 and between MD-1 and MD-3 were –155 to –28.

Conclusions:

Data demonstrate that a short-term soccer-training camp in preparation for international competition induces detectable perturbations to mucosal immunity. Future studies should monitor SIgA (as a practical and noninvasive measure of immunity) alongside internal and external measures of training load in an attempt to strategically individualize training and nutritional strategies that may support optimal preparation for high-level competition.

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Simon Fryer, Tabitha Dickson, Stephen Hillier, Lee Stoner, Carl Scarrott and Nick Draper

Venipuncture is expensive, invasive, and impractical for many sport-science and clinical-based settings. Salivary free cortisol is often cited as a noninvasive practical alternative. However, when cortisol concentrations exceed the corticosteroid-binding globulin (CBG) point of 500 nmol/L, a lack of agreement between salivary and venous blood cortisol has been found. Alternatively, capillary blood may present a minimally invasive, cost-effective, and practical surrogate for determining cortisol concentration.

Purpose:

The aim of this study was to determine whether cortisol concentrations sampled from capillary blood and saliva accurately reflect those found in venous blood across a large range of concentrations after intense exercise.

Methods:

Eleven healthy aerobically trained male subjects were recruited. Capillary, salivary, and venous blood samples were collected before and after (immediately and 5, 10, 15, and 20 min after) a treadmill VO2 max test.

Results:

Capillary and venous concentrations increased at a similar rate after exercise (Cohen d.14–.33), increasing up to 15 min postexercise before a decline was seen. Salivary cortisol values increased at a slower rate than venous and capillary cortisol but continued to increase 15 min postexercise (Cohen d .19–.47 and .09–.72, respectively).

Conclusions:

Capillary cortisol accurately reflects concentrations assayed from venous blood across a range of values below and above the CBG binding point. Capillary sampling provides a minimally invasive, cost-effective, practical surrogate for assessment of hypothalamic-pituitary-gland function.

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Christof A. Leicht, Nicolette C. Bishop, Thomas A.W. Paulson, Katy E. Griggs and Victoria L. Goosey-Tolfrey

Purpose:

Altered autonomic innervation in tetraplegic individuals has been shown to depress certain immune parameters at rest and alter exercise-related salivary immunoglobulin A (sIgA) responses. The purpose of this study was to examine resting sIgA responses as a function of training load and episodes of upper respiratory symptoms (URS) in elite tetraplegic athletes.

Methods:

Resting saliva samples were obtained from 14 tetraplegic athletes at 12 predefined time points over 5 months and analyzed for sIgA. Occurrence of self-reported URS and training load was recorded throughout the study’s duration. Regression analyses were performed to investigate the relationship between sIgA responses and training load. Furthermore, the relationships between sIgA responses and URS occurrence were examined.

Results:

sIgA secretion rate was negatively correlated with training load (P = .04), which only accounted for 8% of the variance. No significant relationships were found between sIgA responses and subsequent URS occurrence. Finally, sIgA responses did not differ between athletes with and without recorded URS during the study period.

Conclusions:

In line with findings in ablebodied athletes, negative relationships between sIgA secretion rate and training load were found in tetraplegic athletes. This may explain some of the higher infection risk in wheelchair athletes with a high training load, which has been previously observed in paraplegic athletes. However, the nonsignificant relationship between sIgA responses and URS occurrence brings into question the use of sIgA as a prognostic tool for the early detection of URS episodes in the studied population.

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Amy B. Cadwallader and Bob Murray

Whenever athletes willfully or accidentally ingest performance-enhancing drugs or other banned substances (such as drugs of abuse), markers of those drugs can be detected in biological samples (e.g., biofluids: urine, saliva, blood); in the case of some drugs, that evidence can be apparent for many weeks following the last exposure to the drug. In addition to the willful use of prohibited drugs, athletes can accidentally ingest banned substances in contaminated dietary supplements or foods and inadvertently fail a drug test that could mean the end of an athletic career and the loss of a good reputation. The proliferation of performance-enhancing drugs and methods has required a corresponding increase in the analytical tools and methods required to identify the presence of banned substances in biofluids. Even though extraordinary steps have been taken by organizations such as the World Anti-Doping Agency to limit the use of prohibited substances and methods by athletes willing to cheat, it is apparent that some athletes continue to avoid detection by using alternative doping regimens or taking advantage of the limitations in testing methodologies. This article reviews the testing standards and analytical techniques underlying the procedures used to identify banned substances in biological samples, setting the stage for future summaries of the testing required to establish the use of steroids, stimulants, diuretics, and other prohibited substances.

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C. Martyn Beaven, Will G. Hopkins, Kier T. Hansen, Matthew R. Wood, John B. Cronin and Timothy E. Lowe

Introduction:

Interest in the use of caffeine as an ergogenic aid has increased since the International Olympic Committee lifted the partial ban on its use. Caffeine has beneficial effects on various aspects of athletic performance, but its effects on training have been neglected.

Purpose:

To investigate the acute effect of caffeine on the exercise-associated increases in testosterone and cortisol in a double-blind crossover study.

Methods:

Twenty-four professional rugby-league players ingested caffeine doses of 0, 200, 400, and 800 mg in random order 1 hr before a resistance-exercise session. Saliva was sampled at the time of caffeine ingestion, at 15-min intervals throughout each session, and 15 and 30 min after the session. Data were log-transformed to estimate percent effects with mixed modeling, and effects were standardized to assess magnitudes.

Results:

Testosterone concentration showed a small increase of 15% (90% confidence limits, ± 19%) during exercise. Caffeine raised this concentration in a dose-dependent manner by a further small 21% (± 24%) at the highest dose. The 800-mg dose also produced a moderate 52% (± 44%) increase in cortisol. The effect of caffeine on the testosterone:cortisol ratio was a small decline (14%; ± 21%).

Conclusion:

Caffeine has some potential to benefit training outcomes via the anabolic effects of the increase in testosterone concentration, but this benefit might be counteracted by the opposing catabolic effects of the increase in cortisol and resultant decline in the testosterone:cortisol ratio.

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Christian Cook, C. Martyn Beaven, Liam P. Kilduff and Scott Drawer

Introduction:

This study aimed to determine whether caffeine ingestion would increase the workload voluntarily chosen by athletes in a limited-sleep state.

Methods:

In a double-blind, crossover study, 16 professional rugby players ingested either a placebo or 4 mg/kg caffeine 1 hr before exercise. Athletes classified themselves into nondeprived (8 hr+) or sleep-deprived states (6 hr or less). Exercise comprised 4 sets of bench press, squats, and bent rows at 85% 1-repetition maximum. Athletes were asked to perform as many repetitions on each set as possible without failure. Saliva was collected before administration of placebo or caffeine and again before and immediately after exercise and assayed for testosterone and cortisol.

Results:

Sleep deprivation produced a very large decrease in total load (p = 1.98 × 10−7). Caffeine ingestion in the nondeprived state resulted in a moderate increase in total load, with a larger effect in the sleep-deprived state, resulting in total load similar to those observed in the nondeprived placebo condition. Eight of the 16 athletes were identified as caffeine responders. Baseline testosterone was higher (p < .05) and cortisol trended lower in non-sleep-deprived athletes. Changes in hormones from predose to preexercise correlated to individual workload responses to caffeine. Testosterone response to exercise increased with caffeine compared with placebo, as did cortisol response.

Conclusions:

Caffeine increased voluntary workload in professional athletes, even more so under conditions of self-reported limited sleep. Caffeine may prove worthwhile when athletes are tired, especially in those identified as responders.

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Katrina D. DuBose and Andrew J. McKune

The relationship between physical activity levels, salivary cortisol, and the metabolic syndrome (MetSyn) score was examined. Twenty-three girls (8.4 ± 0.9 years) had a fasting blood draw, waist circumference and blood pressure measured, and wore an ActiGraph accelerometer for 5 days. Saliva samples were collected to measure cortisol levels. Previously established cut points estimated the minutes spent in moderate, vigorous, and moderate-to-vigorous physical activity. A continuous MetSyn score was created from blood pressure, waist circumference, high-density-lipoprotein (HDL), triglyceride, and glucose values. Correlation analyses examined associations between physical activity, cortisol, the MetSyn score, and its related components. Regression analysis examined the relationship between cortisol, the MetSyn score, and its related components adjusting for physical activity, percent body fat, and sexual maturity. Vigorous physical activity was positively related with 30 min post waking cortisol values. The MetSyn score was not related with cortisol values after controlling for confounders. In contrast, HDL was negatively related with 30 min post waking cortisol. Triglyceride was positively related with 30 min post waking cortisol and area under the curve. The MetSyn score and many of its components were not related to cortisol salivary levels even after adjusting for physical activity, body fat percentage, and sexual maturity.