This investigation assessed the effect of dietary nitrate (NO) supplementation, in the form of beetroot juice (BR), on repeat-sprint performance in normoxia and normobaric hypoxia. 12 male team-sport athletes (age 22.3 ± 2.6 y, VO53.1 ± 8.7 mL.kg.min) completed three exercise trials involving a 10 min submaximal warm-up and 4 sets of cycling repeat-sprint efforts (RSE; 9 × 4 s) at sea level (CON), or at 3000 m simulated altitude following acute supplementation (140 mL) with BR (HYP; 13 mmol NO) or NOdepleted BR placebo (HYP). Peak (PPO) and mean (MPO) power output, plus work decrement were recorded during the RSE task, while oxygen consumption (VO) was measured during the warm-up. There were no significant differences observed between HYPand HYPfor PPO or MPO; however, work decrement was reduced in the first RSE set in HYPcompared with HYP. There was a moderate effect for VOto be lower following BR at the end of the 10 min warm-up (ES = 0.50 ± 0.51). Dietary NOmay not improve repeat-sprint performance in hypoxia but may reduce VOduring submaximal exercise. Therefore, BR supplementation may be more effective for performance improvement during predominantly aerobic exercise.

BACKGROUND: Ageing is associated with a significant reduction in skeletal muscle carnosine which has been linked with a reduction in the buffering capacity of muscle and in theory, may increase the rate of fatigue during exercise. Supplementing beta-alanine has been shown to significantly increase skeletal muscle carnosine. The purpose of this study, therefore, was to examine the effects of ninety days of beta-alanine supplementation on the physical working capacity at the fatigue threshold (PWCFT) in elderly men and women.

METHODS: Using a double-blind placebo controlled design, twenty-six men (n = 9) and women (n = 17) (age +/- SD = 72.8 +/- 11.1 yrs) were randomly assigned to either beta-alanine (BA: 800 mg x 3 per day; n = 12; CarnoSyntrade mark) or Placebo (PL; n = 14) group. Before (pre) and after (post) the supplementation period, participants performed a discontinuous cycle ergometry test to determine the PWCFT.

RESULTS: Significant increases in PWCFT (28.6%) from pre- to post-supplementation were found for the BA treatment group (p<0.05), but no change was observed with PL treatment. These findings suggest that ninety days of BA supplementation may increase physical working capacity by delaying the onset of neuromuscular fatigue in elderly men and women.

CONCLUSION: We suggest that BA supplementation, by improving intracellular pH control, improves muscle endurance in the elderly. This, we believe, could have importance in the prevention of falls, and the maintenance of health and independent living in elderly men and women.

High-intensity interval training has drawn significant interest for its ability to elicit similar training responses with less training volume compared to traditional moderate-intensity protocols. The purpose of this study was to examine the effect of co-ingestion of branched-chain amino acids (BCAA), arginine, and citrulline on 8× 50 m high-intensity interval swim performance in trained young swimmers. This study used a randomized cross-over design. Eight male (age 15.6 ± 1.3 years) and eight female (age 15.6 ± 0.9 years) swimmers completed both amino acids (AA) and placebo (PL) trials. The participants ingested 0.085 g/kg body weight BCAA, 0.05 g/kg body weight arginine and 0.05 g/kg body weight citrulline before the swim test in the AA trial. The average 50 m time was significantly shorter in the AA trial than that in the PL trial. The AA trial was faster than the PL trial in the first, second, and the seventh laps. The AA trial showed significantly higher plasma BCAA concentrations and lower tryptophan/BCAA ratio. The other biochemical parameters and ratings of perceived exertion were similar between the two trials. The results showed that BCAA, arginine, and citrulline, allowed the participants to swim faster in a high-intensity interval protocol in young swimmers.

PURPOSE: The aim of the study was to assess the effect of breathing and physical exercise on pulmonary functions, apnea-hypopnea index (AHI), and quality of life in patients with obstructive sleep apnea syndrome (OSAS).

METHODS: Twenty patients with mild to moderate OSAS were included in the study either as exercise or control group. The control group did not receive any treatment, whereas the exercise group received exercise training. Exercise program consisting of breathing and aerobic exercises was applied for 1.5 h 3 days weekly for 12 weeks. Two groups were assessed through clinical and laboratory measurements after 12 weeks. In the evaluations, bicycle ergometer test was used for exercise capacity, pulmonary function test, maximal inspiratory-expiratory pressure for pulmonary functions, polysomnography for AHI, sleep parameters, Functional Outcomes of Sleep Questionnaire (FOSQ), Short Form-36 (SF-36) for quality of sleep and health-related quality of health, Epworth Sleepiness Scale for daytime sleepiness, and anthropometric measurements for anthropometric characteristics.

RESULTS: In the control group, the outcomes prior to and following 12-weeks follow-up period were found to be similar. In the exercise group, no change was found in the anthropometric and respiratory measurements (P>0.05), whereas significant improvements were found in exercise capacity, AHI, and FOSQ and SF-36 (P<0.05). After the follow-up period, it was shown that improvement in the experimental group did not lead to a statistically significant difference between the two groups (P>0.05).

CONCLUSIONS: Exercise appears not to change anthropometric characteristics and respiratory functions while it improves AHI, health-related quality of life, quality of sleep, and exercise capacity in the patients with mild to moderate OSAS.

BACKGROUND:The aim of this study was to analyze the response of selected components of the immune system in rowers to maximal physical exercise, and to verify if this response could be modulated by supplementation with L-theanine.

METHOD:The double-blind study included 20 members of the Polish Rowing Team. The subjects were randomly assigned to the supplemented group (n = 10), receiving 150 mg of L-theanine extract for 6 weeks, or to the placebo group (n = 10). The participants performed a 2000-m test on a rowing ergometer at the beginning (1st examination) and at the end of the supplementation period (2nd examination). Blood samples were obtained from the antecubital vein before each exercise test, 1 min after completing the test, and after a 24-h recovery. Subpopulations of T regulatory lymphocytes (Tregs) (CD4+/CD25+/CD127-), cytotoxic lymphocytes (CTLs) (CD8+/TCRαβ+), natural killer (NK) cells (CD3-/CD16+/CD56+) and TCRδγ-positive (Tδγ) cells were determined by means of flow cytometry. The levels of interleukin 2 (IL-2), interleukin 4 (IL-4), interleukin 10 (IL-10), interferon gamma (INF-ɤ) and total antioxidant capacity (TAC) were determined with commercially available diagnostic kits.

RESULTS:Supplementation with L-theanine contributed to a significant post-exercise decrease in IL-10 concentration, which was reflected by higher values of IL-2 to IL-10 and IFN-γ to IL-10 ratios. Moreover, a significant post-recovery decrease in CTL count, Treg to NK and Treg to CTL ratios was observed in the supplemented group.

CONCLUSION:Despite the decrease in the number of some cytotoxic cells (CTLs) and an increase in the proportion of Tregs to CTLs, supplementation with LTE seems to exert a beneficial effect on a disrupted Th1/Th2 balance in elite athletes, as shown by the decrease in IL-10 concentration.

PURPOSE:To investigate the effects of supplementation with tart cherry juice (TCJ) on markers of recovery after intermittent exercise under habitual dietary conditions.

METHODS:Using a randomized, single-blind, placebo (PLA)-controlled, independent-groups design, 20 team-sport players (8 male and 12 female; age 26 [4] y, height 175.4 [9.6] cm, body mass 70.2 [12.6] kg) were divided equally into 2 groups and consumed either TCJ or PLA twice per day for 8 consecutive days while following their normal dietary habits. Participants completed an adapted version of the Loughborough Intermittent Shuttle Test (LIST) on day 6 of supplementation. Countermovement jump, 20-m sprint, maximal voluntary isometric contraction, and delayed onset muscle soreness were assessed at baseline and 1, 24, and 48 hours post-LIST. Blood markers of muscle damage (creatine kinase) and inflammation (C-reactive protein) were taken presupplementation, immediately pre-LIST, and 1, 24, and 48 hours post-LIST. Data were analyzed using a repeated-measures analysis of variance.

RESULTS:Countermovement jump, 20-m sprint, and maximal voluntary isometric contraction showed significantly faster recovery with TCJ (P<.05) at 24 and 48 hours post-LIST. A significant interaction effect (P<.05) was observed for muscle soreness; however, Bonferroni post hoc analysis could not identify when the significant differences between TCJ and PLA occurred. There were no significant differences throughout recovery between TCJ and PLA for C-reactive protein and creatine kinase (P<.05).

CONCLUSION:The results suggest that TCJ, in addition to habitual diet, can accelerate recovery after intermittent exercise and therefore extend the efficacy of TCJ in accelerating recovery in team sports.

The effects of vitamin C supplementation on the alterations in the circulating concentrations of cortisol, adrenaline, interleukin-10 (IL-10) and interleukin-1 receptor antagonist (IL-1Ra) which accompany ultramarathon running were measured using immuno-chemiluminescence, radioimmunoassay and ELISA procedures. Forty-five participants in the 1999 Comrades 90 km marathon were divided into equal groups (n = 15) receiving 500 mg/day Vit C (VC-500), 1500 mg/day Vit C (VC-1500) or placebo (P) for 7 days before the race, on the day of the race, and for 2 days following completion. Runners recorded dietary intake before, during and after the race and provided 35 ml blood samples 15 - 18 hrs before the race, immediately post-race, 24 hrs post race and 48 hrs post-race. Twenty-nine runners (VC-1500, n = 12; VC-500, n = 10; P, n = 7) complied with all study requirements. All post-race concentrations were adjusted for plasma volume changes. Analyses of dietary intakes and blood glucose and anti-oxidant status on the day preceding the race and the day of the race did not reveal that carbohydrate intake or plasma vitamins E and A were significant confounders in the study. Mean pre-race concentrations of serum vitamin C in VC-500 and VC-1500 groups (128 +/- 31 and 153 +/- 34 micromol/l) were significantly higher than in the P group (83 +/- 39 micromol/l). Immediate post-race serum cortisol was significantly lower in the VC-1500 group (p < 0.05) than in P and VC-500 groups. When the data from VC-500 and P groups was combined (n = 17), immediate post-race plasma adrenaline, IL-10 and IL-1Ra concentrations were also significantly lower (p < 0.05) in the VC-1500 group. The study demonstrates an attenuation, albeit transient, of both the adrenal stress hormone and anti-inflammatory polypeptide response to prolonged exercise in runners who supplemented with 1500 mg vitamin C per day when compared to < or = 500 mg per day.

OBJECTIVE:Contradictory data between the Insulin-Like Growth Factor System (IGF) system and exercise may be due to alteration in IGF binding proteins. Vitamin D (D) deficiency has been related to muscle weakness and Insulin Like Growth Factor Binding Protein 3 (IGFBP3). A Vit. D and acute exercise merge is proposed to modify the IGF system.

DESIGN:D insufficient and deficient men (39.0±8.6yo with serum D (25OH D) 20.0±7.7ng/mL) did 1h of stretching (ST), aerobic (AB), and resistance (RT) exercises, before and after 28d of 4000IU/d Vit. D3 (D, n=6) or Placebo (P, n=7). ST, a time/attention control visit, interchanged unreceptive movements. AB was moderate intensity treadmill walking. RT rotated moderate strength 50% 1-RM repetitions (15, 10) of squat, bench press, leg press, and lat pull down. Serum Total IGF1 (TIGF1), Insulin Like Growth Factor Binding Protein 1 (IGFBP1), and IGFBP3 were measured before (T1, fasting), immediately after (T2), and 2h post (T3) exercise.

RESULTS:After ST, IGFBP3 was greater in the D group at T2 (2948, 2130ng/mL; p<0.03) and T3 (3087, 2212; p<0.02). During RT, TIGF1 decreased in the Placebo (P) group from T1 to T3 (151.4, 107.3ng/mL; p<0.05), while IGFBP1 increased in the D group from T1 to T3 (26.5, 96.2ng/mL; p<0.05). RT IGFBP3 was greater at T1, T2, and T3 in the D group (2932.5, 2110.7; p<0.03), (3163.9, 2392.5; p<0.04), and (3355.3, 2353.1; p<0.01). In AB, IGFBP3 was greater in the D group at T2 (3128.6, 2226.3.0; p<0.04) and T3 (2949.7, 2135.1; p<0.05).

CONCLUSION:D supplementation amplified IGFBP3 after low or moderate activity which may increase the delivery of IGF1 to tissues. Resistance exercise with D not only increased IGFBP3 and IGFBP1 levels but also conserved TIGF1 levels, possibly shifting the IGF system for enriched muscle well-being.

Vitamin Dsupplementation can affect the strength and power of an athlete, however the effect on endurance performance remains unclear. Twenty-seven recreational male combat athletes with at least 12 months experience within combat sports were recruited (age: 24 ± 4 years, stature: 176 ± 6 cm, weight: 77 ± 14 kg). Participants completed baseline testing for blood haemoglobin and haematocrit, upper and lower body VOand upper and lower body Wingate. Following testing participants were stratified to 50000IU (D1), 80000IU (D2) or 110000IU (D3) of vitamin Dper week. They then completed a 6-week placebo period followed by a 6-week supplementation period. Retesting was carried out after the placebo and supplementation period. There was a significant effect for time for haemoglobin and haematocrit, upper and lower body VOand upper body Wingate power (p<0.01) but no effect for dose of vitamin D given. Performance data was normalised to vitamin D intake and there was a moderate effect size between D1 and D2 for lower body VO(d=0.6), upper body VO(d=0.13) and upper body average power (d=0.75), with a large effect size between D1 and D2 for haemoglobin (d=1.19), haematocrit (d=0.93) and upper body peak power (d=0.95). There was a large effect size for D1 compared to D3 for all variables (d>0.8). Therefore, there is no additional benefit to increasing dose above 500000IU vitamin D per week. Given the endurance adaptations from vitamin D supplementation and the importance of endurance for combat performance, recreational combat athletes should supplement at 50000IU per week for six weeks.

PURPOSE:The objective of this study is to verify the beneficial effects of whey protein (WP) supplementation on health promotion and enhance exercise performance in an aerobic-exercise training protocol.

METHODS:In total, 40 male Institute of Cancer Research mice (4 wk old) were divided into four groups (n = 10 per group): sedentary control with vehicle (SC) or WP supplementation (4.1 g·kg, SC + WP), and exercise training with vehicle (ET) or WP supplementation (4.1 g·kg, ET + WP). Animals in the ET and ET + WP groups underwent swimming endurance training for 6 wk, 5 d·wk. Exercise performance was evaluated by forelimb grip strength and exhaustive swimming time as well as by changes in body composition and biochemical parameters at the end of the experiment.

RESULTS:ET significantly decreased final body and muscle weight and levels of albumin, total protein, blood urea nitrogen, creatinine, total cholesterol, and triacylglycerol. ET significantly increased grip strength; relative weight (%) of liver, heart, and brown adipose tissue (BAT); and levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, creatine kinase, and total bilirubin. WP supplementation significantly decreased final body, muscle, liver, BAT, and kidney weight and relative weight (%) of muscle, liver, and BAT as well as levels of aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and uric acid. In addition, WP supplementation slightly increased endurance time and significantly increased grip strength and levels of albumin and total protein.

CONCLUSION:WP supplementation improved exercise performance, body composition, and biochemical assessments in mice and may be an effective ergogenic aid in aerobic exercise training.

PURPOSE:Postactivation potentiation (PAP) exercise with added whole-body vibration (WBV) has been suggested as a potential way to acutely improve sprint performance. In cycling, there are many competitions and situations where sprinting abilities are important. In the present study we investigated the effect of adding WBV to warm-up procedures on subsequent cycle sprint performance.

METHODS:Eleven well-trained cyclists participated in the study. All cyclists performed a familiarization session before two separate test sessions in randomized order. Each session included a standardized warm-up followed by one of the following preconditioning exercises; 30 s of half-squats without WBV or 30 s of half-squats with WBV at 40 Hz. A 15 s Wingate sprint was performed one minute after the preconditioning exercise.

RESULTS:Performing preconditioning exercise with WBV at 40 Hz resulted in superior peak power output compared to preconditioning exercise without WBV (1413±257 W vs. 1353±213 W, p=0.04) and a tendency towards superior mean power output during a 15 s all-out sprint (850±119 W vs. 828±101 W, p=0.08). Effect sizes showed a moderate practical effect of WBV vs. no WBV on both peak and mean power output.

CONCLUSIONS:In conclusion, preconditioning exercise performed with WBV at 40 Hz seems to have a positive effect on cycling sprint performance in young well-trained cyclists. This suggests that athletes can incorporate body-loaded squats with WBV into preparations to specific sprint training to improve the quality of the sprint training and also in order to improve sprint performance in relevant competitions.

PURPOSE:Postactivation potentiation (PAP) exercise with added whole-body vibration (WBV) has been suggested as a potential way to acutely improve sprint performance. In cycling, there are many competitions and situations where sprinting abilities are important. In the present study we investigated the effect of adding WBV to warm-up procedures on subsequent cycle sprint performance.

METHODS:Eleven well-trained cyclists participated in the study. All cyclists performed a familiarization session before two separate test sessions in randomized order. Each session included a standardized warm-up followed by one of the following preconditioning exercises; 30 s of half-squats without WBV or 30 s of half-squats with WBV at 40 Hz. A 15 s Wingate sprint was performed one minute after the preconditioning exercise.

RESULTS:Performing preconditioning exercise with WBV at 40 Hz resulted in superior peak power output compared to preconditioning exercise without WBV (1413±257 W vs. 1353±213 W, p=0.04) and a tendency towards superior mean power output during a 15 s all-out sprint (850±119 W vs. 828±101 W, p=0.08). Effect sizes showed a moderate practical effect of WBV vs. no WBV on both peak and mean power output.

CONCLUSIONS:In conclusion, preconditioning exercise performed with WBV at 40 Hz seems to have a positive effect on cycling sprint performance in young well-trained cyclists. This suggests that athletes can incorporate body-loaded squats with WBV into preparations to specific sprint training to improve the quality of the sprint training and also in order to improve sprint performance in relevant competitions.