-
1.
The impact of a competitive event and the efficacy of a lactic acid bacteria-fermented soymilk extract on the gut microbiota and urinary metabolites of endurance athletes: An open-label pilot study.
Fukuchi, M, Sugita, M, Banjo, M, Yonekura, K, Sasuga, Y
PloS one. 2022;(1):e0262906
Abstract
Diet and exercise can alter the gut microbiota, but recent studies have assessed the impact of athletic competition on gut microbiota and host metabolites. We designed an open-label pilot study to investigate the effects of both official competition and a multi-strain lactic acid bacteria-fermented soymilk extract (LEX) on the gut microbiota in Japanese college endurance athletes. The analysis of fecal 16S rRNA metagenome and urinary metabolites was used to identify changes in gut microbiota composition and host metabolism. When the fecal microbiota were investigated before and after a race without using of a supplement (pre-observation period), there was an increase in the phylum Firmicutes and decrease in Bacteroidetes. However, no changes in these phyla were seen before and after a race in those who consumed LEX. Before and after LEX ingestion, changes in urinary metabolites included a significant reduction in yeast and fungal markers, neurotransmitters, and mitochondrial metabolites including the TCA cycle. There were several correlations between urinary metabolites and the composition of fecal microbiota. For example, the level of tricarballylic acid was positively correlated with the composition ratio of phylum Firmicutes (Pearson's r = 0.66; p < 0.01). The bacterial species Parabacteroides distasonis was also found to correlate moderately with several urinary metabolites. These findings suggest two possibilities. First, endurance athletes experience significant fluctuations in gut microbiota after a single competition. Second, LEX ingestion may improve yeast and fungal overgrowth in the gastrointestinal tract and enhancing mitochondrial metabolic function.
-
2.
A 1-week diet break improves muscle endurance during an intermittent dieting regime in adult athletes: A pre-specified secondary analysis of the ICECAP trial.
Peos, JJ, Helms, ER, Fournier, PA, Krieger, J, Sainsbury, A
PloS one. 2021;(2):e0247292
Abstract
Athletes undergoing energy restriction for weight/fat reduction sometimes apply 'diet breaks' involving increased energy intake, but there is little empirical evidence of effects on outcomes. Twenty-six resistance-trained athletes (11/26 or 42% female) who had completed 12 weeks of intermittent energy restriction participated in this study. Participants had a mean (SD) age of 29.3 (6.4) years, a weight of 72.7 (15.9) kg, and a body fat percentage of 21.3 (7.5) %. During the 1-week diet break, energy intake was increased (by means of increased carbohydrate intake) to predicted weight maintenance requirements. While the 1-week diet break had no significant effect on fat mass, it led to small but significant increases in mean body weight (0.6 kg, P<0.001), fat-free mass (0.7 kg, P<0.001) and in resting energy expenditure, from a mean (and 95% confidence interval) of 7000 (6420 to 7580) kJ/day to 7200 (6620 to 7780) kJ/day (P = 0.026). Overall, muscle endurance in the legs (but not arms) improved after the diet break, including significant increases in the work completed by the quadriceps and hamstrings in a maximum-effort 25-repetition set, with values increasing from 2530 (2170 to 2890) J to 2660 (2310 to 3010) J (P = 0.018) and from 1280 (1130 to 1430) J to 1380 (1220 to 1540) J (P = 0.018) following the diet break, respectively. However, muscle strength did not change. Participants reported significantly lower sensations of hunger (P = 0.017), prospective consumption (P = 0.020) and irritability (P = 0.041) after the diet break, and significantly higher sensations of fullness (P = 0.002), satisfaction (P = 0.002), and alertness (P = 0.003). In summary, a 1-week diet break improved muscle endurance in the legs and increased mental alertness, and reduced appetite and irritability. With this considered, it may be wise for athletes to coordinate diet breaks with training sessions that require muscle endurance of the legs and/or mental focus, as well as in the latter parts of a weight loss phase when increases in appetite might threaten dietary adherence. Trial registration: Australian New Zealand Clinical Trials Registry Reference Number: ACTRN12618000638235 anzctr.org.au.
-
3.
RaceRunning training improves stamina and promotes skeletal muscle hypertrophy in young individuals with cerebral palsy.
Hjalmarsson, E, Fernandez-Gonzalo, R, Lidbeck, C, Palmcrantz, A, Jia, A, Kvist, O, Pontén, E, von Walden, F
BMC musculoskeletal disorders. 2020;(1):193
Abstract
BACKGROUND Individuals with cerebral palsy (CP) are less physically active, spend more time sedentary and have lower cardiorespiratory endurance as compared to typically developed individuals. RaceRunning enables high-intensity exercise in individuals with CP with limited or no walking ability, using a three-wheeled running bike with a saddle and a chest plate for support, but no pedals. Training adaptations using this type of exercise are unknown. METHODS Fifteen adolescents/young adults (mean age 16, range 9-29, 7 females/8 males) with CP completed 12 weeks, two sessions/week, of RaceRunning training. Measurements of cardiorespiratory endurance (6-min RaceRunning test (6-MRT), average and maximum heart rate, rate of perceived exertion using the Borg scale (Borg-RPE)), skeletal muscle thickness (ultrasound) of the thigh (vastus lateralis and intermedius muscles) and lower leg (medial gastrocnemius muscle) and passive range of motion (pROM) of hip, knee and ankle were collected before and after the training period. RESULTS Cardiorespiratory endurance increased on average 34% (6-MRT distance; pre 576 ± 320 m vs. post 723 ± 368 m, p < 0.001). Average and maximum heart rate and Borg-RPE during the 6-MRT did not differ pre vs. post training. Thickness of the medial gastrocnemius muscle increased 9% in response to training (p < 0.05) on the more-affected side. Passive hip flexion increased (p < 0.05) on the less-affected side and ankle dorsiflexion decreased (p < 0.05) on the more affected side after 12 weeks of RaceRunning training. CONCLUSIONS These results support the efficacy of RaceRunning as a powerful and effective training modality in individuals with CP, promoting both cardiorespiratory and peripheral adaptations.
-
4.
Pre-Exercise Glucose Ingestion May Improve Endurance Capacity in East Asian Student Athletes with Lower Blood Glucose Response.
Koma, R, Terasawa, N
Journal of nutritional science and vitaminology. 2020;(2):150-157
Abstract
The main purpose of this study was to investigate the influence of pre-exercise glucose ingestion after a 2.5-h fast on the endurance capacity and blood glucose response in East Asian athletes who is expected to have genetically low insulin response. A total of 8 Japanese student athletes ingested 1.5 g/kg body mass of glucose (G trial) or 0.5 g/kg body mass of artificial sweetener dissolved in water (P trial) 30 min before exercise test after consuming a standardized breakfast. The exercise test comprised 40 min cycling exercise at 50% maximal oxygen uptake (VO2max), immediately followed by cycling to exhaustion at 70% VO2max. Before analyzing the data, we grouped the subjects into two groups depending on whether they showed rapid increase in blood glucose at the onset of exercise (increase rate in LOW group is <20% and HIGH group is ≥20%) to evaluate subject's insulin response to glucose feeding. No subjects developed rebound hypoglycemia (<70 mg/dL) in the G trial of both group. Significantly higher blood glucose during exercise was recognized only in the G trial of LOW group. Although no significant difference was observed between the two trials of both group, cycling time to exhaustion in the LOW group tended to increase because of glucose ingestion. These results suggest that pre-exercise ingestion of glucose in East Asian student athletes does not induce rebound hypoglycemia regardless of difference in individual insulin responses. Furthermore, individuals with low insulin responses seem to improve endurance performance with glucose ingestion before exercise.
-
5.
[The efficiency of branched chain aminoacids (BCAA) in the nutrition of combat sport athletes].
Trushina, EN, Vybornov, VD, Riger, NA, Mustafina, OK, Solntsevа, TN, Timonin, AN, Zilova, IS, Radzhabkadiev, RM
Voprosy pitaniia. 2019;(4):48-56
Abstract
Balanced nutrition of athletes involves the usage of both ordinary products and complexes of functional food ingredients that contribute to improving the performance of athletes, strengthening the immune system. One of the main components of specialized foods that are widely used in sports' nutrition and food supplements are branched chain aminoacids (BCAA): valine, leucine, isoleucine. The aim of the work was to study the effect of the BCAA intake on the parameters of body composition and the immune status of combat sport athletes during the training period. Material and methods. The object of the study was 20 athletes (masters of sports and candidates for masters of sports in combat sports: sambo, judo) at the age of 17-18 years. Athletes were distributed into 2 groups. Athletes of the main group (n=10) for 4 weeks in addition to the main diet were supplemented with BCAA at a dosage of 5 g per day. The athletes of the control group (n=10) received the main diet without BCAA inclusion. Examination of athletes of both groups was carried out at the beginning of the research and after 4 weeks of the observation period. The actual nutrition of athletes and daily energy consumption have been studied, body composition, the quantitative composition of subpopulations of peripheral blood lymphocytes, cytokine profile and hematological parameters have been determined. Results and discussion. As a result of a comprehensive survey of athletes, the positive effect of BCAA intake on the phase angle value (7.35±0.28 vs 6.41±0.32 at the beginning of the study, p<0.05) and muscle mass (25.1±0.8 vs 23.4±0.6 kg, p<0.10) has been demonstrated. In the control group these parameters did not change statistically significantly (7.05±0.25 vs 6.78±0.42 and 24.1±1.7 vs 23.8±1.5 kg). The athletes of the main group showed an increase in erythrocyte hemoglobin content (30.0±0.3 vs 29.0±0.2 pg, p<0.05). The relative content of basophilic leukocytes in athletes of the main group decreased by the end of the observation period - from 0.69±0.05 to 0.54±0.05% (p<0.05), that indicated an increase of immune resistance. The biomarker of the immunotropic effect of BCAA was the suppression of IL-4 production (1.6±0.1 to 1.3±0.1 pg/ml, p<0.05) synthesized by Th2 lymphocytes, with switching response to cellular immunity. Conclusion. The results of this study provide evidence of the effectiveness of BCAA usage in sports' nutrition for maintaining sport performance, immunity, and the adaptive potential of combat sport athletes.
-
6.
Dynamics of the power-duration relationship during prolonged endurance exercise and influence of carbohydrate ingestion.
Clark, IE, Vanhatalo, A, Thompson, C, Joseph, C, Black, MI, Blackwell, JR, Wylie, LJ, Tan, R, Bailey, SJ, Wilkins, BW, et al
Journal of applied physiology (Bethesda, Md. : 1985). 2019;(3):726-736
Abstract
We tested the hypotheses that the parameters of the power-duration relationship, estimated as the end-test power (EP) and work done above EP (WEP) during a 3-min all-out exercise test (3MT), would be reduced progressively after 40 min, 80 min, and 2 h of heavy-intensity cycling and that carbohydrate (CHO) ingestion would attenuate the reduction in EP and WEP. Sixteen participants completed a 3MT without prior exercise (control), immediately after 40 min, 80 min, and 2 h of heavy-intensity exercise while consuming a placebo beverage, and also after 2 h of heavy-intensity exercise while consuming a CHO supplement (60 g/h CHO). There was no difference in EP measured without prior exercise (260 ± 37 W) compared with EP after 40 min (268 ± 39 W) or 80 min (260 ± 40 W) of heavy-intensity exercise; however, after 2 h EP was 9% lower compared with control (236 ± 47 W; P < 0.05). There was no difference in WEP measured without prior exercise (17.9 ± 3.3 kJ) compared with after 40 min of heavy-intensity exercise (16.1 ± 3.3 kJ), but WEP was lower (P < 0.05) than control after 80 min (14.7 ± 2.9 kJ) and 2 h (13.8 ± 2.7 kJ). Compared with placebo, CHO ingestion negated the reduction of EP following 2 h of heavy-intensity exercise (254 ± 49 W) but had no effect on WEP (13.5 ± 3.4 kJ). These results reveal a different time course for the deterioration of EP and WEP during prolonged endurance exercise and indicate that EP is sensitive to CHO availability.NEW & NOTEWORTHY The parameters of the power-duration relationship [critical power (CP) and the curvature constant (W')] have typically been considered to be static. Here we report the time course for reductions in CP and W', as estimated with the 3-min all-out cycle test, during 2 h of heavy-intensity exercise. We also show that carbohydrate ingestion during exercise preserves CP, but not W', without altering muscle glycogen depletion. These results provide new mechanistic and practical insight into the power-duration curve and its relationship to exercise-related fatigue development.
-
7.
Comparison of metabolic adaptations between endurance- and sprint-trained athletes after an exhaustive exercise in two different calf muscles using a multi-slice 31 P-MR spectroscopic sequence.
Moll, K, Gussew, A, Nisser, M, Derlien, S, Krämer, M, Reichenbach, JR
NMR in biomedicine. 2018;(4):e3889
Abstract
Measurements of exercise-induced metabolic changes, such as oxygen consumption, carbon dioxide exhalation or lactate concentration, are important indicators for assessing the current performance level of athletes in training science. With exercise-limiting metabolic processes occurring in loaded muscles, 31 P-MRS represents a particularly powerful modality to identify and analyze corresponding training-induced alterations. Against this background, the current study aimed to analyze metabolic adaptations after an exhaustive exercise in two calf muscles (m. soleus - SOL - and m. gastrocnemius medialis - GM) of sprinters and endurance athletes by using localized dynamic 31 P-MRS. In addition, the respiratory parameters VO2 and VCO2 , as well as blood lactate concentrations, were monitored simultaneously to assess the effects of local metabolic adjustments in the loaded muscles on global physiological parameters. Besides noting obvious differences between the SOL and the GM muscles, we were also able to identify distinct physiological strategies in dealing with the exhaustive exercise by recruiting two athlete groups with opposing metabolic profiles. Endurance athletes tended to use the aerobic pathway in the metabolism of glucose, whereas sprinters produced a significantly higher peak concentration of lactate. These global findings go along with locally measured differences, especially in the main performer GM, with sprinters revealing a higher degree of acidification at the end of exercise (pH 6.29 ± 0.20 vs. 6.57 ± 0.21). Endurance athletes were able to partially recover their PCr stores during the exhaustive exercise and seemed to distribute their metabolic activity more consistently over both investigated muscles. In contrast, sprinters mainly stressed Type II muscle fibers, which corresponds more to their training orientation preferring the glycolytic energy supply pathway. In conclusion, we were able to analyze the relation between specific local metabolic processes in loaded muscles and typical global adaptation parameters, conventionally used to monitor the training status of athletes, in two cohorts with different sports orientations.
-
8.
Two-week inhalation of budesonide increases muscle Na,K ATPase content but not endurance in response to terbutaline in men.
Hostrup, M, Jessen, S, Onslev, J, Clausen, T, Porsbjerg, C
Scandinavian journal of medicine & science in sports. 2017;(7):684-691
Abstract
While chronic systemic administration of glucocorticoids increases muscle Na+ ,K+ ATPase content, such effect is unexplored after therapeutic inhalation. We investigated the effect of therapeutic inhalation of the glucocorticoid budesonide on Na+ ,K+ ATPase content of skeletal muscle in men. Ten healthy trained subjects, aged 23 ± 4 years (mean ± 95% CI), participated in the study. Before and after 2 weeks of daily inhalation of budesonide (1.6 mg/day), a biopsy was taken from the vastus lateralis muscle for measurement of Na+ ,K+ ATPase content and blood samples were drawn for determination of plasma budesonide, cortisol, and K+ . Subjects' performance during cycling to fatigue at 90% of incremental peak power output (iPPO) was measured in response to 4 mg inhaled terbutaline to maximally stimulate Na+ ,K+ ATPase activity. Plasma concentrations of budesonide rose to 5.0 ± 1.6 nM with the intervention, whereas no changes were observed in plasma cortisol. Muscle Na+ ,K+ ATPase content increased (P ≤ 0.01) by 46 ± 34 pmol/(g wet wt) (17% increase) with the intervention. Cycling performance at 90% of iPPO did not change (P = 0.21) with the intervention (203 vs 214 s) in response to terbutaline. The present observations show that therapeutic inhalation of glucocorticoids increases muscle Na+ ,K+ ATPase content, but does not enhance high-intensity cycling endurance in response to terbutaline.
-
9.
Assessment of pN-GAL as a marker of renal function in elite cyclists during professional competitions.
Andreazzoli, A, Fossati, C, Spaccamiglio, A, Salvo, R, Quaranta, F, Minganti, C, Di Luigi, L, Borrione, P
Journal of biological regulators and homeostatic agents. 2017;(3):829-835
Abstract
Glomerular filtration rate (GFR) has been shown to be lower than physiological values during exercise with a strong negative correlation with exercise intensity. Among new markers of renal function, neutrophil gelatinase-associated lipocalin (NGAL) seems to be very promising. It is an early, sensitive and specific marker of acute kidney injury (AKI) with two isoforms: plasma NGAL (pNGAL) and urinary NGAL (uNGAL). The aim of the present study was to assess acute variations in NGAL plasma levels after performing high endurance physical exercise in a group of professional cyclists during the two major European professional cycling competitions (Giro D’Italia and Tour de France). Eighteen professional cyclistis were recruited for the study. A blood sample was collected during rest (after 8 hours fasting) and immediately after the competition (mountain stages) in order to assess the effect of very intense exercise on kidney function by measuring the variations of pNGAL. We also assessed plasma levels of creatinine, creatine-kinase (CK), LDH, transaminases and electrolytes. The results showed that Creatinine, CK and electrolytes levels remained almost stable between rest and post-competition. The levels of transaminases and NGAL showed a mild increase between rest and post-competition, with a significant difference between the two values only for transaminases (p=0.005). However, post-competition values of all investigated variables remained within the physiological range. The results of the present study suggest that even if NGAL values mildly rose after competition, no kidney injury occurred in these highly trained athletes during mountain stages of professional competitions. Other studies in literature confirmed that high endurance physical exercise seems not to cause renal injury in elite athletes. This is probably due to adaptive mechanisms of renal function and to the adaptation to physical stress gained with training.
-
10.
UX007 for the treatment of long chain-fatty acid oxidation disorders: Safety and efficacy in children and adults following 24weeks of treatment.
Vockley, J, Burton, B, Berry, GT, Longo, N, Phillips, J, Sanchez-Valle, A, Tanpaiboon, P, Grunewald, S, Murphy, E, Humphrey, R, et al
Molecular genetics and metabolism. 2017;(4):370-377
Abstract
BACKGROUND Long-chain fatty acid oxidation disorders (LC-FAOD) lead to accumulation of high concentrations of potentially toxic fatty acid intermediates. Newborn screening and early intervention have reduced mortality, but most patients continue to experience frequent hospitalizations and significant morbidity despite treatment. The deficient energy state can cause serious liver, muscle, and heart disease, and may be associated with an increased risk of sudden death. Triheptanoin is a medium odd-chain fatty acid. Anaplerotic metabolites of triheptanoin have the potential to replace deficient tricarboxylic acid (TCA) cycle intermediates, resulting in net glucose production as a novel energy source for the treatment of LC-FAOD. STUDY DESIGN A single-arm, open-label, multicenter Phase 2 safety and efficacy study evaluated patients with severe LC-FAOD evidenced by ongoing related musculoskeletal, cardiac, and/or hepatic events despite treatment. After a four-week run-in on current regimen, investigational triheptanoin (UX007) was titrated to a target dose of 25-35% of total daily caloric intake. Patients were evaluated on several age/condition-eligible endpoints, including submaximal exercise tests to assess muscle function/endurance (12-minute walk test; 12MWT) and exercise tolerance (cycle ergometry), and health related quality of life (HR-QoL). Results through 24weeks of treatment are presented; total study duration is 78weeks. RESULTS Twenty-nine patients (0.8 to 58years) were enrolled; most qualified based on severe musculoskeletal disease. Twenty-five patients (86%) completed the 24-week treatment period. At Week 18, eligible patients (n=8) demonstrated a 28% increase (LS mean=+181.9 meters; p=0.087) from baseline (673.4meters) in 12MWT distance. At Week 24, eligible patients (n=7) showed a 60% increase in watts generated (LS mean=+409.3W; p=0.149) over baseline (744.6W) for the exercise tolerance test. Improvements in exercise tests were supported by significant improvements from baseline in the adult (n=5) self-reported SF-12v2 physical component summary score (LS mean=+8.9; p<0.001). No difference from baseline was seen in pediatric parent-reported (n=5) scores (SF-10) at Week 24. Eighteen patients (62%) had treatment-related adverse events, predominantly gastrointestinal (55%), mild-to-moderate in severity, similar to that seen with prior treatment with medium chain triglyceride (MCT) oil. One patient experienced a treatment-related serious adverse event of gastroenteritis. One patient discontinued from study due to diarrhea of moderate severity; the majority of patients (25/29; 86%) elected to continue treatment in the extension period. CONCLUSIONS In patients with severe LC-FAOD, UX007 interim study results demonstrated improved exercise endurance and tolerance, and were associated with positive changes in self-reported HR-QoL.