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The effect of probiotic supplementation on performance, inflammatory markers and gastro-intestinal symptoms in elite road cyclists.
Schreiber, C, Tamir, S, Golan, R, Weinstein, A, Weinstein, Y
Journal of the International Society of Sports Nutrition. 2021;(1):36
Abstract
BACKGROUND Elite athletes may suffer from impaired immune function and gastro-intestinal (GI) symptoms, which may affect their health and may impede their performance. These symptoms may be reduced by multi-strain probiotic supplementation. Therefore, the aim of the current study is to examine the effects of probiotic supplementation on aerobic fitness characteristics, inflammatory markers and incidence and severity of GI symptoms in elite cyclists. METHODS Twenty-seven male cyclists, ranked elite or category 1 level competitions, were randomly assigned to a multi-strain probiotic-supplemented group (E, n = 11) or placebo group (C, n = 16). All participants visited the laboratory at the beginning of the study and following 90 d of supplementation/placebo. Prior to testing, all participants completed a GI symptoms questionnaire and underwent physical and medical examination, and anthropometric measurements. Venous blood was drawn for inflammatory markers analysis. The cyclists then underwent maximal oxygen consumption (VO2max) test and time-to-fatigue (TTF) test at 85 % of maximal power, 3 h following the VO2max test. All testing procedures were repeated after 90 d of probiotic / placebo treatment (double blind design). RESULTS Lower incidence of nausea, belching, and vomiting (P < 0.05) at rest, and decreased incidence of GI symptoms during training were found in E group vs. C Group, respectively (∆GI -0.27 ± 0.47 % vs. 0.08 ± 0.29 %, P = 0.03), no significant changes were observed in the incidence of total overall GI symptoms (∆GI -5.6 ± 14.7 % vs. 2.6 ± 11.6 %, P = 0.602) Mean rate of perceived exertion (RPE) values during the TTF were lower in E group (∆RPE: -0.3 ± 0.9 vs. 0.8 ± 1.5, P = 0.04). No significant changes were measured between and within groups in VO2max and TTF values, mean levels of C-reactive protein (CRP), IL-6-and tumor necrosis factor alpha (TNFα) values following treatment. CONCLUSIONS Probiotics supplementation may have beneficial effects on GI symptoms in elite cyclists. Future studies, using higher doses and during different training seasons, might help understanding the effects of probiotic supplementation on elite athletes' health and performance. TRIAL REGISTRATION NIH clinicaltrial.gov #NCT02756221 Registered 25 April 2016.
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Effect of sprint cycling and stretch-shortening cycle exercises on the neuromuscular, immune and stress indicators in young men.
Verbickas, V, Baranauskiene, N, Eimantas, N, Kamandulis, S, Rutkauskas, S, Satkunskiene, D, Sadauskas, S, Brazaitis, M, Skurvydas, A
Journal of physiology and pharmacology : an official journal of the Polish Physiological Society. 2017;(1):125-132
Abstract
Selection of optimal physical load is essential for desired adaptation including health benefits. We hypothesized that neuromuscular, immune and stress indicators will be higher after energy demanding sprint interval exercise (SIE) than to mechanically demanding stretch-shortening cycle exercise (SSE). The main aim of this study was to assess and compare the kinetics of blood brain-derived neurotrophic factor (BDNF), norepinephrine (NE) and cortisol (as stress indicators) and proinflammatory (IL-6) and anti-inflammatory (IL-10) cytokines within 24 hours after metabolically demanding SIE and after muscle damage inducing SSE. Twenty healthy physically active young men randomly assigned to two equal groups to complete 12 bouts of 5 s stationary cycling sprints every 3 min (SIE) or 200 drop-jumps with 30 s interval between each jump (SSE), respectively. Quadriceps muscle maximal voluntary contraction torque and voluntary activation and soreness were measured and blood samples collected before and 2 min, 1 hour, 12 hours and 24 hours after the SIE and SSE. The BDNF, cortisol, IL-6 and NE levels increased more at 2 min after SIE than SSE (P < 0.05); however, the IL-10 level did not differ between SIE and SSE. BDNF and cortisol levels were decreased at 24 h after both SIE and especially after SSE. The higher was the initial BDNF level, the greater was its decrease at 24 h after both type of exercise. Before exercise BDNF level correlated closely with the change in central fatigue (decrease in voluntary activation) after both SIE and SSE. We thus conclude that both metabolically demanding SIE and muscle damage inflicting SSE induced long-lasting decrease in circulating BDNF which may not promote brain health. The level of circulating BDNF, but not cortisol, IL-6, IL-10 or NE, was associated with changes in central motor fatigue.
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Impact of intensified training and carbohydrate supplementation on immunity and markers of overreaching in highly trained cyclists.
Svendsen, IS, Killer, SC, Carter, JM, Randell, RK, Jeukendrup, AE, Gleeson, M
European journal of applied physiology. 2016;(5):867-77
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Abstract
PURPOSE To determine effects of intensified training (IT) and carbohydrate supplementation on overreaching and immunity. METHODS In a randomized, double-blind, crossover design, 13 male cyclists (age 25 ± 6 years, VO2max 72 ± 5 ml/kg/min) completed two 8-day periods of IT. On one occasion, participants ingested 2 % carbohydrate (L-CHO) beverages before, during and after training sessions. On the second occasion, 6 % carbohydrate (H-CHO) solutions were ingested before, during and after training, with the addition of 20 g of protein in the post-exercise beverage. Blood samples were collected before and immediately after incremental exercise to fatigue on days 1 and 9. RESULTS In both trials, IT resulted in decreased peak power (375 ± 37 vs. 391 ± 37 W, P < 0.001), maximal heart rate (179 ± 8 vs. 190 ± 10 bpm, P < 0.001) and haematocrit (39 ± 2 vs. 42 ± 2 %, P < 0.001), and increased plasma volume (P < 0.001). Resting plasma cortisol increased while plasma ACTH decreased following IT (P < 0.05), with no between-trial differences. Following IT, antigen-stimulated whole blood culture production of IL-1α was higher in L-CHO than H-CHO (0.70 (95 % CI 0.52-0.95) pg/ml versus 0.33 (0.24-0.45) pg/ml, P < 0.01), as was production of IL-1β (9.3 (95 % CI 7-10.4) pg/ml versus 6.0 (5.0-7.8) pg/ml, P < 0.05). Circulating total leukocytes (P < 0.05) and neutrophils (P < 0.01) at rest increased following IT, as did neutrophil:lymphocyte ratio and percentage CD4+ lymphocytes (P < 0.05), with no between-trial differences. CONCLUSION IT resulted in symptoms consistent with overreaching, although immunological changes were modest. Higher carbohydrate intake was not able to alleviate physiological/immunological disturbances.
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Influence of gender, menstrual phase, and oral contraceptive use on immunological changes in response to prolonged cycling.
Timmons, BW, Hamadeh, MJ, Devries, MC, Tarnopolsky, MA
Journal of applied physiology (Bethesda, Md. : 1985). 2005;(3):979-85
Abstract
This study determined the influence of gender, menstrual phase (MP), and oral contraceptive (OC) use on immunological changes in response to endurance exercise. Twelve women and 11 men similar in age, aerobic power, and activity level cycled for 90 min at 65% maximal aerobic power. Women were OC users (n = 6) or nonusers (NOC) and cycled during the follicular (Fol) and the luteal (Lut) phases. Venous blood was collected before and after exercise to determine leukocyte counts, IL-6 concentrations, and cortisol. Higher resting levels of neutrophils (approximately 1.5-fold) and cortisol (approximately 2.5-fold) were found in OC vs. NOC and men. Exercise-induced immune cell count and IL-6 changes were similar between men and NOC, except for an approximately 38% greater lymphocyte response in NOC vs. men (P = 0.07). Neutrophil, monocyte, and lymphocyte responses to exercise during Lut in OC were greater than during Fol and also greater than the responses in men (P < or = 0.003). Changes in immune cell counts were consistently greater during Lut in OC vs. NOC, regardless of MP, but only neutrophil responses reached statistical significance (P = 0.01). The exercise-induced change in IL-6 was approximately 80% greater in NOC vs. OC during Fol (P = 0.06), but it was similar between these groups during Lut. Cortisol changes with exercise were not different between groups or MP. These results highlight the necessity to control for gender, and in particular OC use, when designing studies evaluating exercise and immunology.