The Effect of Alginate Encapsulated Plant-Based Carbohydrate and Protein Supplementation on Recovery and Subsequent Performance in Athletes.

The main purpose of this study was to investigate the effect of a novel alginate-encapsulated carbohydrate-protein (CHO-PRO ratio 2:1) supplement (ALG) on cycling performance. The ALG, designed to control the release of nutrients, was compared to an isocaloric carbohydrate-only control (CON). Alginate encapsulation of CHOs has the potential to reduce the risk of carious lesions. METHODS: In a randomised cross-over clinical trial, 14 men completed a preliminary test over 2 experimental days separated by ~6 days. An experimental day consisted of an exercise bout (EX1) of cycling until exhaustion at W~73%, followed by 5 h of recovery and a subsequent time-to-exhaustion (TTE) performance test at W~65%. Subjects ingested either ALG (0.8 g CHO/kg/hr + 0.4 g PRO/kg/hr) or CON (1.2 g CHO/kg/hr) during the first 2 h of recovery. RESULTS: Participants cycled on average 75.2 ± 5.9 min during EX1. Levels of plasma branched-chain amino acids decreased significantly after EX1, and increased significantly with the intake of ALG during the recovery period. During recovery, a significantly higher plasma insulin and glucose response was observed after intake of CON compared to ALG. Intake of ALG increased plasma glucagon, free fatty acids, and glycerol significantly. No differences were found in the TTE between the supplements (p = 0.13) nor in the pH of the subjects' saliva. CONCLUSIONS: During the ALG supplement, plasma amino acids remained elevated during the recovery. Despite the 1/3 less CHO intake with ALG compared to CON, the TTE performance was similar after intake of either supplement.

Effects of In-Exercise Carbohydrate Supplementation on Prolonged High-Intensity Exercise Performance in Oral Contraceptive Users.

PURPOSE: To examine the impact of oral contraceptive (OC) phases on performance, physiological, and subjective responses to prolonged, intensive exercise when carbohydrate (CHO) stores are reduced. METHODS: Ten well-trained female cyclists using monophasic OC completed 4 identical trials (>150 min) under conditions of in-trial 60-g·h-1 CHO supplementation (CHO+) or placebo (CHO-) during the sugar- (SUG) and active-pill (ACT) phases of their OC cycle. Each trial comprised two 400-kcal time trials (TT) separated by 1 hour of submaximal cycling at first ventilatory threshold. RESULTS: Change in completion time from TT1 to TT2 was minimized in CHO+ compared with CHO- (4.06 [2.55] vs 6.08 [5.33] min; P = .019, effect size = -0.36). An interaction effect of OC and CHO was observed for time to complete TT (P = .006), mean TT power (P = .002), mean TT heart rate (P = .002), and posttrial emotional balance (P = .020) and negative emotional state (P = .033). In ACT, mean TT power and heart rate were higher in CHO+ when compared with CHO-, resulting in faster TTs in CHO+ and improved posttrial emotional well-being. When CHO was not supplemented, TT power and heart rate were higher in SUG when compared with ACT, resulting in faster TTs in SUG and improved posttrial emotional balance. CONCLUSION: CHO depletion during ACT negatively influenced TT performance and emotional well-being when compared with SUG. Irrespective of OC pill phase, CHO supplementation should be prioritized to sustain performance and improve postexercise recovery-stress balance.

Dietary Supplementation with Lauric Acid Improves Aerobic Endurance in Sedentary Mice via Enhancing Fat Mobilization and Glyconeogenesis.

BACKGROUND: Lauric acid (LA), a major, natural, medium-chain fatty acid, is considered an efficient energy substrate for intense exercise and in patients with long-chain fatty acid ß-oxidation disorders. However, few studies have focused on the role of LA in exercise performance and related glucolipid metabolism in vivo. OBJECTIVES: We aimed to investigate the effect of dietary supplementation with LA on exercise performance and related metabolic mechanisms. METHODS: Male C57BL/6N mice (14 wk old) were fed a basal diet or a diet containing 1% LA, and a series of exercise tests, including a high-speed treadmill test, aerobic endurance exercises, a 4-limb hanging test, and acute aerobic exercises, were performed. RESULTS: Dietary supplementation with 1.0% LA accelerated the recovery from fatigue after explosive exercise (P < 0.05) and improved aerobic endurance and muscle strength in sedentary mice (P = 0.039). Lauric acid intake not only changed muscle fatty acid profiles, including increases in C12:0 and n-6/n-3 PUFAs (P < 0.001) and reductions in C18:0, C20:4n-6, C22:6n-3, and n-3 PUFAs (P < 0.05) but also enhanced fat mobilization from adipose tissue and fatty acid oxidation in the liver, at least partly via the AMP-activated protein kinase-acetyl CoA carboxylase pathway (P < 0.05). Likewise, LA supplementation promoted liver glyconeogenesis and conserved muscular glycogen during acute aerobic exercise (P < 0.05), which was accompanied by an increase in the mitochondrial DNA copy number and Krebs cycle activity in skeletal muscle (P < 0.05). CONCLUSIONS: Dietary supplemental LA serves as an efficient energy substrate for sedentary mice to improve aerobic exercise endurance and muscle strength through regulation of glucolipid metabolism. These findings imply that LA supplementation might be a promising nutritional strategy to improve aerobic exercise performance in sedentary people.

Effect of isolated and combined ingestion of caffeine and citrulline malate on resistance exercise and jumping performance: a randomized double-blind placebo-controlled crossover study.

PURPOSE: The aim of this study was to explore the isolated and combined effects of caffeine and citrulline malate (CitMal) on jumping performance, muscular strength, muscular endurance, and pain perception in resistance-trained participants. METHODS: Using a randomized and double-blind study design, 35 resistance-trained males (n = 18) and females (n = 17) completed four testing sessions following the ingestion of isolated caffeine (5 mg/kg), isolated CitMal (12 g), combined doses of caffeine and CitMal, and placebo. Supplements were ingested 60 min before performing a countermovement jump (CMJ) test (outcomes included jump height, rate of force development, peak force, and peak power), one-repetition maximum (1RM) squat and bench press, and repetitions to muscular failure in the squat and bench press with 60% of 1RM. Pain perception was evaluated following the repetitions to failure tests. The study was registered at ISRCTN (registration number: ISRCTN11694009). RESULTS: Compared to the placebo condition, isolated caffeine ingestion and co-ingestion of caffeine and CitMal significantly enhanced strength in 1RM bench press (Cohen's d: 0.05-0.06; 2.5-2.7%), muscular endurance in the squat (d: 0.46-0.58; 18.6-18.7%) and bench press (d: 0.48-0.64; 9.3-9.5%). However, there was no significant difference between isolated caffeine ingestion and caffeine co-ingested with CitMal, and isolated CitMal supplementation did not have an ergogenic effect in any outcome. No main effect of condition was found in the analysis for CMJ-derived variables, 1RM squat and pain perception. CONCLUSION: Caffeine ingestion appears to be ergogenic for muscular strength and muscular endurance, while adding CitMal does not seem to further enhance these effects.

Effects of calcium supplementation to resuscitation fluids in endurance horses: A randomized, blinded, clinical trial.

BACKGROUND: The addition of calcium to resuscitation fluids is a common practice in horses, but studies evaluating the effects of calcium supplementation are limited. In healthy horses, decreases in heart rate and changes in serum electrolyte concentrations have been reported. HYPOTHESIS: Calcium gluconate administration at a rate of 0.4 mg/kg/min to eliminated endurance horses with metabolic problems will affect heart rate, gastrointestinal sounds, and serum electrolyte concentrations. ANIMALS: Endurance horses eliminated from the Tevis Cup 100-mile (160 km) endurance ride for metabolic problems and requiring IV fluid therapy were eligible. METHODS: Sixteen horses were randomly assigned to receive 0.4 mg/kg/min of calcium (23% calcium gluconate solution) over 1 hour diluted in 10 L of a non-calcium containing isotonic crystalloid (CAL group) or 10 L of a non-calcium containing isotonic crystalloid (CON group). Staff members administering the fluids were blinded to treatment group. Blood samples were collected and physical examinations performed before and after treatment. Heart rates were recorded every 15 min during fluid administration. Data were compared using 2-way analysis of variance (ANOVA) with repeated measures for continuous variables and Fisher's exact test for categorical variables. RESULTS: Calcium was associated with lower heart rates 45 min after starting the infusion (P = .002). Gastrointestinal sounds were less likely to improve in the calcium group compared with the control group (P = .005). An increase in plasma phosphorus concentration (P = .03) was associated with calcium administration. CONCLUSIONS: Intravenous calcium supplementation to endurance horses eliminated from competition after development of metabolic problems may decrease heart rate but impairs improvement in gastrointestinal sounds.

The Effect of Acute Pre-Workout Supplement Ingestion on Basketball-Specific Performance of Well-Trained Athletes.

A pre-workout supplement's (PWS; 200 mg caffeine, 3.3 g creatine monohydrate, 3.2 g ß-alanine, 6 g citrulline malate and 5 g branched chained amino acid (BCAA) per dose) acute effects on the alactic (jumping, sprinting, agility), lactic (Running-Based Anaerobic Sprint Test, RAST) and aerobic performance (Yo-Yo Intermittent Recovery Test Level 1, Yo-Yo IRL1 VO2max) of well-trained basketball players was investigated in this double-blind placebo-controlled study. Thirty players (age 18-31 years, height 166-195 cm, weight 70.2-116.7 kg, body fat 10.6-26.4%) were allocated to pre-workout (PWS, n = 15) or placebo (PL, n = 15) groups. Half of the participants in each group performed the evaluations without PWS or PL, while the rest consumed PWS or PL 30 min before the assessments (1st trial) and vice versa (2nd trial). Significant improvements in counter-movement jump (CMJ) (PWS: 4.3 ± 2.1%; PL: 1.2 ± 1.0%), agility (PWS: -2.9 ± 1.8%; PL: 1.8 ± 1.7%), RAST average (PWS: 18.3 ± 9.1%; PL: -2.2 ± 2.0%), minimum power (PWS: 13.7 ± 8.9%; PL: -7.5 ± 5.9%), and fatigue index (PWS: -25.0 ± 0.9%; PL: -4.6 ± 0.6%) were observed in the PWS group vs. the PL group (p < 0.05). No differences were found regarding sprinting, aerobic performance, and blood lactate concentrations. Thus, although players' alactic and lactic anaerobic performance could be improved, peak power, sprinting and aerobic performance are not.

Study of anti-fatigue activity of polysaccharide from fruiting bodies of Armillaria gallica.

Fatigue is a common physiological response that is closely related to energy metabolism. Polysaccharides, as excellent dietary supplements, have been proven to have a variety of pharmacological activities. In this study, A 23.007 kDa polysaccharide from Armillaria gallica (AGP) was purified and performed structural characterization, including analysis of homogeneity, molecular weight and monosaccharide composition. Methylation analysis is used to analyze the glycosidic bond composition of AGP. The mouse model of acute fatigue was used to evaluate the anti-fatigue effect of AGP. AGP-treatment improved exercise endurance in mice and reduced fatigue symptoms caused by acute exercise. AGP regulated the levels of adenosine triphosphate, lactic acid, blood urea nitrogen and lactate dehydrogenase, muscle glycogen and liver glycogen of acute fatigue mice. AGP affected the composition of intestinal microbiota, the changes of some intestinal microorganisms are correlated with fatigue and oxidative stress indicators. Meanwhile, AGP reduced oxidative stress levels, increased antioxidant enzyme activity and regulated the AMP-dependent protein kinase/nuclear factor erythroid 2-related factor 2 signaling pathway. AGP exerted an anti-fatigue effect through modulation of oxidative stress, which is related to intestinal microbiota.

Phosphate Loading Does not Improve 30-km Cycling Time-Trial Performance in Trained Cyclists.

Phosphate is integral to numerous metabolic processes, several of which strongly predict exercise performance (i.e., cardiac function, oxygen transport, and oxidative metabolism). Evidence regarding phosphate loading is limited and equivocal, at least partly because studies have examined sodium phosphate supplements of varied molar mass (e.g., mono/di/tribasic, dodecahydrate), thus delivering highly variable absolute quantities of phosphate. Within a randomized cross-over design and in a single-blind manner, 16 well-trained cyclists (age 38 ± 16 years, mass 74.3 ± 10.8 kg, training 340 ± 171 min/week; mean ± SD) ingested either 3.5 g/day of dibasic sodium phosphate (Na2HPO4: 24.7 mmol/day phosphate; 49.4 mmol/day sodium) or a sodium chloride placebo (NaCl: 49.4 mmol/day sodium and chloride) for 4 days prior to each of two 30-km time trials, separated by a washout interval of 14 days. There was no evidence of any ergogenic benefit associated with phosphate loading. Time to complete the 30-km time trial did not differ following ingestion of sodium phosphate and sodium chloride (3,059 ± 531 s vs. 2,995 ± 467 s). Accordingly, neither absolute mean power output (221 ± 48 W vs. 226 ± 48 W) nor relative mean power output (3.02 ± 0.78 W/kg vs. 3.08 ± 0.71 W/kg) differed meaningfully between the respective intervention and placebo conditions. Measures of cardiovascular strain and ratings of perceived exertion were very closely matched between treatments (i.e., average heart rate 161 ± 11 beats per minute vs. 159 ± 12 beats per minute; Δ2 beats per minute; and ratings of perceived exertion 18 [14-20] units vs. 17 [14-20] units). In conclusion, supplementing with relatively high absolute doses of phosphate (i.e., >10 mmol daily for 4 days) exerted no ergogenic effects on trained cyclists completing 30-km time trials.

Creatine supplementation and endurance performance: surges and sprints to win the race.

Creatine supplementation is an effective ergogenic aid to augment resistance training and improve intense, short duration, intermittent performance. The effects on endurance performance are less known. The purpose of this brief narrative review is to discuss the potential mechanisms of how creatine can affect endurance performance, defined as large muscle mass activities that are cyclical in nature and are >~3 min in duration, and to highlight specific nuances within the literature. Mechanistically, creatine supplementation elevates skeletal muscle phosphocreatine (PCr) stores facilitating a greater capacity to rapidly resynthesize ATP and buffer hydrogen ion accumulation. When co-ingested with carbohydrates, creatine enhances glycogen resynthesis and content, an important fuel to support high-intensity aerobic exercise. In addition, creatine lowers inflammation and oxidative stress and has the potential to increase mitochondrial biogenesis. In contrast, creatine supplementation increases body mass, which may offset the potential positive effects, particularly in weight-bearing activities. Overall, creatine supplementation increases time to exhaustion during high-intensity endurance activities, likely due to increasing anaerobic work capacity. In terms of time trial performances, results are mixed; however, creatine supplementation appears to be more effective at improving performances that require multiple surges in intensity and/or during end spurts, which are often key race-defining moments. Given creatines ability to enhance anaerobic work capacity and performance through repeated surges in intensity, creatine supplementation may be beneficial for sports, such as cross-country skiing, mountain biking, cycling, triathlon, and for short-duration events where end-spurts are critical for performance, such as rowing, kayaking, and track cycling.

Similar performance after intake of carbohydrate plus whey protein and carbohydrate only in the early phase after non-exhaustive cycling.

AIM: The aim of the present study was to compare performance 5 h after a 90-min endurance training session when either carbohydrate only or carbohydrate with added whey hydrolysate or whey isolate was ingested during the first 2 h of the recovery period. METHODS: Thirteen highly trained competitive male cyclists completed three exercise and diet interventions (double-blinded, randomized, crossover design) separated by 1 week. The 90-min morning session (EX1) included a 60 min time-trial (TT60 ). Immediately and 1 h after exercise, participants ingested either (1) 1.2 g carbohydrate∙kg-1 ∙h-1 (CHO), (2) 0.8 g carbohydrate∙kg-1 ∙h-1 + 0.4 g isolate whey protein∙kg-1 ∙h-1 (ISO) or (3) 0.8 g carbohydrate∙kg-1 ∙h-1 + 0.4 g hydrolysate whey protein∙kg-1 ∙h-1 (HYD). Additional intakes were identical between interventions. After 5 h of recovery, participants completed a time-trial performance (TTP ) during which a specific amount of work was performed. Blood and urine were collected throughout the day. RESULTS: TTP did not differ significantly between dietary interventions (CHO: 43:54 ± 1:36, ISO: 46:55 ± 2:32, HYD: 44:31 ± 2:01 min). Nitrogen balance during CHO was lower than ISO (p < 0.0001) and HYD (p < 0.0001), with no difference between ISO and HYD (p = 0.317). In recovery, the area under the curve for blood glucose was higher in CHO compared to ISO and HYD. HR, VO2 , RER, glucose, and lactate during EX2 were similar between interventions. CONCLUSION: Performance did not differ after 5 h of recovery whether carbohydrate only or isocaloric carbohydrate plus protein was ingested during the first 2 h. Correspondingly, participants were not in negative nitrogen balance in any dietary intervention.

Development of an Instrument to Evaluate the Intake of Liquids, Food and Supplements in Endurance Competitions: Nutritional Intake Questionnaire for Endurance Competitions-NIQEC.

BACKGROUND: In the last few years endurance sports have experienced a great increase in the number of competitions and participants. Dietary-nutritional planning is key for performing well during such competitions. To date, there is no questionnaire expressly developed to be able to analyze the consumption of liquids, foods, and supplements, as well as gastrointestinal problems in these events. This study describes the development of the Nutritional Intake Questionnaire for Endurance Competitions (NIQEC). METHODS: The study was composed in the following phases: (1) Bibliographic search for the most important nutrients, (2) focus groups (17 dietitian-nutritionists and 15 experienced athletes) and generation of items, (3) Delphi surveys, and (4) cognitive interviews. RESULTS: After an initial shaping of the questionnaire with the items that emerged in the focus groups, their relevance was evaluated by means of the Delphi survey, which showed more than 80% approval for most items. Finally, the cognitive interviews indicated that the questionnaire was simple and complete for its purpose. The final NIQEC (n = 50 items) was divided in 5 sections: Demographic data; sports data; consumption of liquids, food and supplements before, during, and after the competition; gastrointestinal complaints, and dietary-nutritional planning for the competition. CONCLUSIONS: The NICEQ is a useful tool that allows collecting information from participants on sociodemographic factors and gastrointestinal complaints, and estimating the intake of liquid, food, and supplements, for endurance competitions.

The Long Way to Establish the Ergogenic Effect of Caffeine on Strength Performance: An Overview Review.

This overview review aimed to describe the evolution of the characteristics of the research on caffeine effects on strength. A total of 189 experimental studies with 3459 participants were included. The median sample size was 15 participants, with an over-representation of men vs. women (79.4 vs. 20.6%). Studies on young participants and elders were scarce (4.2%). Most studies tested a single dose of caffeine (87.3%), while 72.0% used doses adjusted to body mass. Single-dose studies ranged from 1.7 to 7 mg/kg (4.8 ± 1.4 mg/kg), while dose-response studies ranged from 1 to 12 mg/kg. Caffeine was mixed with other substances in 27.0% of studies, although only 10.1% of studies analyzed the caffeine interaction with these substances. Capsules (51.9%) and beverages (41.3%) were the most common forms of caffeine administration. Similar proportions of studies focused on upper (24.9%) or lower body strength 37.6% (37.6% both). Participants' daily intake of caffeine was reported in 68.3% of studies. Overall, the pattern in the study of caffeine's effects on strength performance has been carried out with experiments including 11-15 adults, using a single and moderate dose of caffeine adjusted to participants' body mass in the form of a capsule.

Effects of protein-carbohydrate vs. carbohydrate alone supplementation on immune inflammation markers in endurance athletes: a randomized controlled trial.

PURPOSE: The impact of ingesting carbohydrates alone or combined with proteins to support exercise immune adaptation in endurance athletes is scarcely investigated. The present study compares the effect of ingesting a combined protein-carbohydrate supplement vs. a carbohydrate-only supplement post-workout on immune inflammation markers following a 10 week periodized endurance training program in well-trained athletes. METHODS: Twenty-five men completed the study after being randomly assigned to one of the following intervention groups: combined protein-carbohydrate (PRO-CHO n = 12, 31 ± 9 years, [Formula: see text]O2peak 61.0 ± 5.6 ml.kg-1.min-1) or non-protein isoenergetic carbohydrate (CHO, n = 13, 33 ± 8 years, [Formula: see text]O2peak 60.6 ± 6.9 ml.kg-1.min-1). Treatment consisted of ingesting 24 g of assigned supplement, mixed with 250 ml of orange juice, once a day for 10 weeks immediately post-workout (or before breakfast on non-training days). Measurements were conducted pre- and post-intervention on total leukocytes, leukocyte subsets (i.e., neutrophils, eosinophils, basophils, monocytes, and lymphocytes), and platelets. The inflammatory status was assessed by the neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio (PLR), and the systemic-immune inflammation index (SII). RESULTS: Post-intervention, significant increases were observed for CHO group only for the three inflammatory markers: NLR (p = 0.050, d = 0.58), PLR (p = 0.041, d = 0.60), and SII (p = 0.004, d = 0.81) but not for PRO-CHO (p > 0.05). CONCLUSION: Ingesting a post-workout protein-carbohydrate combined beverage promoted a more favourable immune status than carbohydrate-only ingestion by attenuating cellular inflammation over a 10 week training period in endurance male athletes. TRIAL REGISTRATION: The study was registered in ClinicalTrials.gov with the following ID: NCT02954367. The study was registered by 3 November 2016.

Physical clinical care and artificial-intelligence-guided core resistance training improve endurance and patient-reported outcomes in subjects with lower back pain.

BACKGROUND: Low back pain is an extremely prevalent issue with an extensive impact, ranging from decreased quality of life to lost years of productivity. Many interventions have been developed to alleviate chronic lower back pain, yet it remains a widespread problem. The objective of this study was to examine the role of artificial intelligence guided resistance training relative to clinical variables in subjects experiencing lower back pain. METHODS: 69 out of 108 enrolled and 92 accrued subjects completed the 8-week intervention. Subjects were randomized into four groups (Control, Training, Clinical, or Combined). The Training cohort received supervised artificial-intelligence-guided core-focused resistance training while the Clinical group received clinical care. The Combined group received both clinical care and artificial-intelligence-guided training and the Control group received no treatment. Participants were evaluated using functional testing and patient-reported outcomes at baseline, 4 weeks, and 8 weeks. FINDINGS: In the clinical tests, the Clinical and Combined cohorts showed increased total time for isometric extensor endurance and the Clinical cohort increased total distance traveled in the 6-min walk test at 8 weeks. The Training, Clinical, and Combined groups showed improvements in Patient-reported outcomes after 8 weeks. Most of the significant improvements were only seen at the 8-week evaluation for both the clinical evaluations and Patient-reported outcomes. The Control group did not show significant improvements in any outcome measures. INTERPRETATION: The present data indicate that core-focused interventions, including artificial-intelligence-guided moderate-resistance exercise, can increase objective functional outcomes and patient satisfaction using Patient-reported outcomes in individuals with lower back pain.

Synergistic Effect of Rhodiola rosea and Caffeine Supplementation on the Improvement of Muscle Strength and Muscular Endurance: A Pilot Study for Rats, Resistance Exercise-Untrained and -Trained Volunteers.

Multi-level studies have shown that Rhodiola rosea (RHO) and Caffeine (CAF) have the potential to be nutritional supplements to enhance physical performance in resistance exercise-untrained and -trained subjects. This study examined the synergistic effects of RHO (262.7 mg/kg for rats and 2.4 g for volunteers) and CAF (19.7 mg/kg for rats and 3 mg/kg for volunteers) supplementation on improving physical performance in rats, resistance exercise-untrained volunteers and resistance exercise-trained volunteers. Rats and volunteers were randomly grouped into placebo, CAF, RHO and CAF+RHO and administered accordingly with the nutrients during the training procedure, and pre- and post-measures were collected. We found that RHO+CAF was effective in improving forelimb grip strength (13.75%), erythropoietin (23.85%), dopamine (12.65%) and oxygen consumption rate (9.29%) in the rat model. Furthermore, the current results also indicated that the combination of RHO+CAF significantly increased the bench press one-repetition maximum (1RM) (16.59%), deep squat 1RM (15.75%), maximum voluntary isometric contraction (MVIC) (14.72%) and maximum repetitions of 60% 1RM bench press (22.15%) in resistance exercise-untrained volunteers. Additionally, despite the excellent base level of the resistance exercise-trained volunteers, their deep squat 1RM and MVIC increased substantially through the synergistic effect of RHO and CAF. In conclusion, combined supplementation of RHO+CAF is more beneficial in improving the resistance exercise performance for both resistance exercise-untrained and -trained volunteers. The present results provide practical evidence that the synergies of RHO and CAF could serve as potential supplementary for individuals, especially resistance exercise-trained subjects, to ameliorate their physical performances effectively and safely.

Effect of Acute Ketone Monoester Ingestion on Cardiorespiratory Responses to Exercise and the Influence of Blood Acidosis.

PURPOSE: This study aimed to examine the effect of KE ingestion on exercise cardiac output ( Q˙ ) and the influence of blood acidosis. We hypothesized that KE versus placebo ingestion would increase Q ˙, and coingestion of the pH buffer bicarbonate would mitigate this effect. METHODS: In a randomized, double-blind, crossover manner, 15 endurance-trained adults (peak oxygen uptake (V̇O 2peak ), 60 ± 9 mL·kg -1 ·min -1 ) ingested either 0.2 g·kg -1 sodium bicarbonate or a salt placebo 60 min before exercise, and 0.6 g·kg -1 KE or a ketone-free placebo 30 min before exercise. Supplementation yielded three experimental conditions: basal ketone bodies and neutral pH (CON), hyperketonemia and blood acidosis (KE), and hyperketonemia and neutral pH (KE + BIC). Exercise involved 30 min of cycling at ventilatory threshold intensity, followed by determinations of V̇O 2peak and peak Q ˙. RESULTS: Blood [ß-hydroxybutyrate], a ketone body, was higher in KE (3.5 ± 0.1 mM) and KE + BIC (4.4 ± 0.2) versus CON (0.1 ± 0.0, P < 0.0001). Blood pH was lower in KE versus CON (7.30 ± 0.01 vs 7.34 ± 0.01, P < 0.001) and KE + BIC (7.35 ± 0.01, P < 0.001). Q ˙ during submaximal exercise was not different between conditions (CON: 18.2 ± 3.6, KE: 17.7 ± 3.7, KE + BIC: 18.1 ± 3.5 L·min -1 ; P = 0.4). HR was higher in KE (153 ± 9 bpm) and KE + BIC (154 ± 9) versus CON (150 ± 9, P < 0.02). V̇O 2peak ( P = 0.2) and peak Q ˙ ( P = 0.3) were not different between conditions, but peak workload was lower in KE (359 ± 61 W) and KE + BIC (363 ± 63) versus CON (375 ± 64, P < 0.02). CONCLUSIONS: KE ingestion did not increase Q ˙ during submaximal exercise despite a modest elevation of HR. This response occurred independent of blood acidosis and was associated with a lower workload at V̇O 2peak .

Whole-Body Electromyostimulation Impacts Physiological Responses During Aerobic Running: A Randomized Trial.

Objective: The aim of the current study was to evaluate the physiological and metabolic responses to running with whole-body electromyostimulation (wbEMS) compared to running without electromyostimulation (control, CG). Methods: Twenty healthy participants (9 male/11 female, age 42 ±7 years) conducted an incremental step test with respiratory gas analysis until exhaustion. Trials were conducted as wbEMS and CG in a random order. As outcome measures, (A) objective total exhaustion, (B) athletic responses (max. time and velocity) and (C) physiological and metabolic responses (V'O2/ kg, V'E, EE, RER, lactate) were compared. (D) The impact on the skeletal muscle was assessed prior, 48 h & 72 h after trial. Results: During both trials, participants (A) ran until total exhaustion. Nonetheless, (B) time and velocity till exhaustion as well as (C) RER prior to the first lactate threshold and V'E were reduced with wbEMS. All other correlates did not differ significantly between wbEMS and CG. Following 48 h and 72 h after the trial with wbEMS, (D) the impact on the skeletal muscle was 7- to 9-fold higher compared to baseline values. Values differed significantly to those after running without wbEMS. Conclusion: With the additional stimulation during voluntary activation, wbEMS induces earlier fatigue and a shift in energy metabolism toward fat utilization. Even during aerobic endurance tasks, a great impact on the skeletal muscle indicated by the rise in CK could be observed which promotes wbEMS as an alternative training stimulus that is easy-to-apply and effective during endurance training.

Acute effects of concurrent muscle power and sport-specific endurance exercises on markers of immunological stress response and measures of muscular fitness in highly trained youth male athletes.

PURPOSE: To examine the acute effects of concurrent muscle power and sport-specific endurance exercises order on immunological stress responses, muscular-fitness, and rating-of-perceived-exertion (RPE) in highly trained youth male judo athletes. METHODS: Twenty male participants randomly performed two concurrent training (CT) sessions; power-endurance and endurance-power. Measures of immune response (e.g., white blood cells), muscular-fitness (i.e., counter-movement-jump [CMJ]), RPE, blood-lactate, and -glucose were taken at different time-point (i.e., pre, mid, post, and post6h). RESULTS: There were significant time*order interactions for white blood cells, lymphocytes, granulocytes, granulocyte-lymphocyte-ratio, and systemic-inflammation-index. Power-endurance resulted in significantly larger pre-to-post increases in white blood cells and lymphocytes while endurance-power resulted in significantly larger pre-to-post increases in the granulocyte-lymphocyte-ratio and systemic-inflammation-index. Likewise, significantly larger pre-to-post6h white blood cells and granulocytes increases were observed following power-endurance compared to endurance-power. Moreover, there was a significant time*order interaction for blood-glucose and -lactate. Following endurance-power, blood-lactate and -glucose increased from pre-to-mid but not from pre-to-post. Meanwhile, in power-endurance blood-lactate and -glucose increased from pre-to-post but not from pre-to-mid. A significant time*order interaction was observed for CMJ-force with larger pre-to-post decreases in endurance-power compared to power-endurance. Further, CMJ-power showed larger pre-to-mid performance decreases following power-endurance, compared to endurance-power. Regarding RPE, significant time*order interactions were noted with larger pre-to-mid values following endurance-power and larger pre-to-post values following power-endurance. CONCLUSION: CT induced acute and delayed order-dependent immune cell count alterations in highly trained youth male judo athletes. In general, power-endurance induced higher acute and delayed immunological stress responses compared to endurance-power. CMJ-force and RPE fluctuated during both CT sessions but went back to baseline 6 h post-exercise.

Acute Supplementation with Beta-Alanine Improves Performance in Aerobic-Anaerobic Transition Zones in Endurance Athletes.

To determine the acute effect of low and high-dose BA trials on maximal aerobic speed (MAS) in endurance athletes. We hypothesized that high doses of BA have a greater effect than low doses, both compared to baseline.Twelve male endurance athletes volunteered for the study (age = 21.8 ± 2.37 years, weight = 69.8 ± 4.36 kg, height = 174 ± 5.45 cm, maximal oxygen uptake = 59.6 ± 3.77 mLO2·kg-1·min-1). The experimental design applied was randomized cross-over, double-blind. Treatment included three 6-minute run tests (6-MRT), the first as a baseline, then randomized 6-MRT with low (30 mg·kg-1) and high (45 mg·kg-1) dose BA trials. The 6-MRTs were separated by 72 hours. The main variable of the study was the distance (m) performed in the 6-MRT. Differences between tests were established through ANOVA and Tukey's multiple comparison tests (p < 0.05).The analysis showed significant differences between baseline and both doses (p < 0.001). No significant differences were observed between low and high-dose BA trials (p > 0.05).Both 30 and 45 mg·kg-1 of BA increased physical performance at maximal aerobic speed in endurance athletes. The acute intake formats described in the present investigation may be helpful for endurance athletes training and competing in aerobic-anaerobic transition zones.

L-menthol administration facilitates breathing comfort during exhaustive endurance running and improves running capacity in well-trained runners: A randomized crossover study.

ABSTRACTThis study aimed to clarify the contribution of L-menthol administration to endurande exercise capacity. Thirteen male runners (age, 35.8 ± 7.8 years; peak oxygen uptake, 62.7 ± 6.8 mL kg-1 min-1) ran on treadmills at fixed intensities of their anaerobic thresholds to exhaustion. All participants underwent three trials-water ingestion (W-IG), L-menthol mouth rinsing (M-MR), and L-menthol ingestion (M-IG)- in a random order every 5 min while running. Breathing comfort (BC) was measured immediately after fluid intake. Dyspnea threshold against external inspiratory resistance was examined before and after the running test. The running time with M-IG (1683.9 ± 520.3 s) was longer than that with W-IG (1410.2 ± 465.9 s, effect size [ES] = 0.55). BC with M-IG (2.00 ± 0.74) was higher than that with W-IG (0.42 ± 0.79) at exhaustion (ES > 2.00). The dyspnea threshold after running decreased to 19.2 ± 7.6 cm H2O L-1 s-1 with W-IG, whereas that with M-MR (26.2 ± 6.5 cm H2O L-1 s-1) and M-IG (29.2 ± 2.8 cm H2O L-1 s-1) remained high (p for interaction < 0.001). M-IG facilitated BC during running, improved endurance capacity, and prevented decreases in the dyspnea threshold against external inspiratory resistance after exhaustive running.HighlightsL-menthol ingestion facilitated breathing comfort during high intensity endurance running and improved exhaustive endurance running capacity.Even after exhaustion, L-menthol solution relieved dyspnea sensitivity against external inspiratory resistance.L-menthol ingestion might help athletes improve their endurance running capacity.