Acute ingestion of acetaminophen improves cognitive and repeated high intensity short-term maximal performance in well-trained female athletes: a randomized placebo-controlled trial.

This study examined the effect of acute acetaminophen (ACTP) ingestion on physical performance during the 5 m shuttle run test (5mSRT), attention, mood states, and the perception of perceived exertion (RPE), pain (PP), recovery (PRS), and delayed onset of muscle soreness (DOMS) in well-trained female athletes. In a randomized, placebo-controlled, double-blind, crossover trial, fifteen well-trained female athletes (age 21 ± 2 years, height 165 ± 6 cm, body mass 62 ± 5 kg) swallowed either 1.5 g of ACTP or 1.5 g of placebo. The profile of mood states (POMS) and digit cancellation (DCT) were assessed 45 min postingestion, and 5mSRT was performed 60 min postingestion. The RPE and PP were determined immediately after each 30-s repetition of the 5mSRT, and the PRS and DOMS were recorded at 5 min and 24 h post-5mSRT. For the 5mSRT, ACTP ingestion improved the greatest distance (+ 10.88%, p < 0.001), total distance (+ 11.33%, p = 0.0007) and fatigue index (+ 21.43%, p = 0.0003) compared to PLA. Likewise, the DCT score was better on the ACTP (p = 0.0007) than on the PLA. RPE, PP, PRS, and DOMS scores were improved after ACTP ingestion (p < 0.01 for all comparisons) compared to PLA. POMS scores were enhanced with ACTP ingestion compared to PLA (p < 0.01). In conclusion, this study indicates that acute acetaminophen ingestion can improve repeated high intensity short-term maximal performance, attention, mood states, and perceptions of exertion, pain, recovery, and muscle soreness in well-trained female athletes, suggesting potential benefits for their overall athletic performance and mood state.

Acute ingestion of Ibuprofen does not influence the release of IL-6 or improve self-paced exercise in the heat despite altering cortical activity.

The present study tested the hypothesis that ingesting 800 mg Ibuprofen prior to self-paced cycling at a fixed rating of perceived exertion (RPE) improves performance by attenuating the release of Interleukin (IL)-6 and its signalling molecules, whilst simultaneously modulating cortical activity and cerebral oxygenation to the brain. Eight healthy, recreationally active males ingested 800 mg Ibuprofen or a placebo ~ 1 h prior to performing fixed RPE cycling for 60 min in 35 °C and 60% relative humidity at an intensity of hard to very hard (RPE = 16) with intermittent maximal (RPE = 20) sprints every 10 min. Power output (PO), core and mean skin temperatures (Tc, Tsk), respectively, and heart rate (HR) were measured continuously. Electroencephalography (EEG) recordings at the frontal (Fz), motor (Cz) and Parietal (Pz) areas (90 s) were collected every 5 min. IL-6, soluble glycoprotein receptor (sgp130) and IL-6 receptor (R) were collected at pre-, 30 min and immediately post-exercise. Mean PO, HR, Tc and Tsk, and RPE were not different between trials (P ≥ 0.33). At end-exercise, the change in IL-6, sgp130 and sIL-6R was not different between trials (P ≥ 0.12). The increase in α and ß activity did not differ in any cortices between trials (P ≥ 0.07); however, there was a significant reduction in α/ß activity in the Ibuprofen compared to placebo trials at all sites (P ≤ 0.05). Ingesting a maximal, over-the-counter dose of Ibuprofen prior to exercise in the heat does not attenuate the release of IL-6, nor improve performance, but may influence cortical activity evidenced by a greater reduction in α/ß activity.

Trehalose Improved 20-min Cycling Time-Trial Performance After 100-min Cycling in Amateur Cyclists.

Carbohydrate (CHO) supplementation during endurance exercise can improve performance. However, it is unclear whether low glycemic index (GI) CHO leads to differential ergogenic and metabolic effects compared with a standard high GI CHO. This study investigated the ergogenic and metabolic effects of CHO supplementation with distinct GIs, namely, (a) trehalose (30 g/hr), (b) isomaltulose (30 g/hr), (c) maltodextrin (60 g/hr), and (d) placebo (water). In this double-blind, crossover, counterbalanced, placebo-controlled study, 13 male cyclists cycled a total of 100 min at varied exercise intensity (i.e., 10-min stages at 1.5, 2.0, and 2.5 W/kg; repeated three times plus two 5-min stages at 1.0 W/kg before and after the protocol), followed by a 20-min time trial on four separated occasions. Blood glucose and lactate (every 20 min), heart rate, and ratings of perceived exertion were collected throughout, and muscle biopsies were taken before and immediately after exercise. The results showed that trehalose improved time-trial performance compared with placebo (total work done 302 ± 39 vs. 287 ± 48 kJ; p = .01), with no other differences between sessions (all p ≥ .07). Throughout the 100-min protocol, blood glucose was higher with maltodextrin compared with the other supplements at all time points (all p < .05). Heart rate, ratings of perceived exertion, muscle glycogen content, blood glucose, and lactate were not different between conditions when considering the 20-min time trial (all p > .05). Trehalose supplementation throughout endurance exercise improved cycling performance and appears to be an appropriate CHO source for exercise tasks up to 2 hr. No ergogenic superiority between the different types of CHO was established.

Short-term effects of Lumacaftor/Ivacaftor (Orkambi™) on exertional symptoms, exercise performance, and ventilatory responses in adults with cystic fibrosis.

RATIONALE: Lumacaftor/ivacaftor (LUM/IVA) modestly improves lung function following 1 month of treatment but it is unknown if this translates into improvements in exercise endurance and exertional symptoms. METHODS: Adult CF participants completed a symptom-limited constant load cycling test with simultaneous assessments of dyspnea and leg discomfort ratings pre- and 1 month post-initiation of LUM/IVA. RESULTS: Endurance time, exertional dyspnea and leg discomfort ratings at submaximal exercise did not change significantly. There was a significant inverse correlation between changes in leg discomfort and endurance time (r = - 0.88; p = 0.009) following 1-month of LUM/IVA. CONCLUSIONS: Overall, 1-month of LUM/IVA did not increase endurance time or modify exertional dyspnea or leg discomfort ratings. However, individuals who experienced a reduction in leg discomfort following LUM/IVA had an improvement in endurance time. Future studies with a larger sample size are needed to verify these findings and to assess the long-term effects of LUM/IVA on exercise outcomes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02821130. Registered July 1, 2016.

Self-selected fluid volume and flavor strength does not alter fluid intake, body mass loss, or physiological strain during moderate-intensity exercise in the heat.

INTRODUCTION: The purpose of this study was to determine the effects of ad libitum flavor and fluid intake on changes in body mass (BM) and physiological strain during moderate intensity exercise in the heat. METHODS: Ten subjects (24±3yrs, 7M/3F) performed 60 min of treadmill walking at 1.3 m/s and 7% grade in an environmental chamber set to 33 °C and 10% relative humidity while carrying a 22.7 kg pack on two different occasions. Subjects consumed either plain water or water plus flavor (Infuze), ad libitum, at each visit. Pre and post exercise, fluid consumption (change in fluid reservoir weight) and BM (nude) were measured. During exercise, heart rate (HR), systolic blood pressure (SBP), rate of perceived exertion (RPE), oxygen consumption (VO2), respiratory exchange ratio (RER), core temperature (TC), and physiological strain index (PSI) were recorded every 15 min during exercise. RESULTS: No significant differences were observed for fluid consumption between fluid conditions (512 ± 97.2 mL water vs. 414.3 ± 62.5 mL Infuze). Despite a significant decrease from baseline, there were no significant differences in overall change of BM (Δ -1.18 vs. -0.64 Kg) or percent body weight loss for water and Infuze conditions, respectively (1.58 ± 0.6 and 0.79 ± 0.2%). Furthermore, there were no significant differences in HR (144 ± 6 vs. 143 ± 8 bpm), SBP (157 ± 5 vs. 155 ± 5 mmHg), RPE, VO2 (27.4 ± 0.9 vs. 28.1 ± 1.2 ml/Kg/min), RER, TC (38.1 ± 0.1 vs. 37.0 ± 0.1 °C), and peak PSI (5.4 ± 0.4 vs. 5.7 ± 0.8) between conditions. CONCLUSIONS: Offering individuals the choice to actively manipulate flavor strength did not significantly influence ad libitum fluid consumption, fluid loss, or physiological strain during 60 min of moderate intensity exercise in the heat.

Effect of Humic Acids from Lowland Peat on Endurance of Rats in Forced Swim Test in Relation to Serum Lactate and Corticosterone.

The study substantiated the possibility of using peat humic acids for improving endurance during extreme physical exertion. The mature outbred Wistar rats weighing 200-250 g (n=40) were subjected to forced swim test until complete exhaustion. The humic acids (1%) were administered intragastrically (0.5 ml/100 g body weight) 30 min prior to the test. Chronic administration of peat humic acids for 5 days increased physical capacity and endurance of rats in exhaustive forced swim test without the changes in serum lactate and corticosterone.

Oral taurine improves critical power and severe-intensity exercise tolerance.

This study investigated the effects of acute oral taurine ingestion on: (1) the power-time relationship using the 3-min all-out test (3MAOT); (2) time to exhaustion (TTE) 5% > critical power (CP) and (3) the estimated time to complete (Tlim) a range of fixed target intensities. Twelve males completed a baseline 3MAOT test on a cycle ergometer. Following this, a double-blind, randomised cross-over design was followed, where participants were allocated to one of four conditions, separated by 72 h: TTE + taurine; TTE + placebo; 3MAOT + taurine; 3MAOT + placebo. Taurine was provided at 50 mg kg-1, whilst the placebo was 3 mg kg-1 maltodextrin. CP was higher (P < 0.05) in taurine (212 ± 36 W) than baseline (197 ± 40 W) and placebo (193 ± 35 W). Work end power was not affected by supplement (P > 0.05), yet TTE 5% > CP increased (P < 0.05) by 1.7 min after taurine (17.7 min) compared to placebo (16.0 min) and there were higher (P < 0.001) estimated Tlim across all work targets. Acute supplementation of 50 mg kg-1 of taurine improved CP and estimated performance at a range of severe work intensities. Oral taurine can be taken prior to exercise to enhance endurance performance.

Eicosapentaenoic Acid-Rich Fish Oil Supplementation Inhibits the Decrease in Concentric Work Output and Muscle Swelling of the Elbow Flexors.

OBJECTIVE: The aim of this study was to test the hypothesis that 8-week eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) supplementation improves peripheral muscle performance by concentric contractions (CONs) of elbow flexors in humans. METHODS: Sixteen healthy men were randomly administered with EPA and DHA supplement (EPA, n = 8) or placebo (PL, n = 8) by a double-blind method. The EPA group was administered EPA-rich fish oil, containing 600 mg EPA and 260 mg DHA per day for 8 weeks. The subjects performed 5 sets of 6 maximal CONs of elbow flexors. The work output and peak torque were assessed during exercise. Changes in the maximal voluntary isometric contraction torque, range of motion (ROM), upper arm circumference, muscle fatigue by rating of perceived exertion, transverse relaxation time, cross-sectional area (CSA), and lactate in blood were also assessed before, immediately after, and 1 day after exercise. RESULTS: The work output during CONs in the EPA group was greater than that in the placebo group at the fifth set (EPA group; 94.0 ± 11.7%, placebo group; 82.5 ± 11.7%, p < 0.05). In addition, ROM in the EPA group was significantly greater than that in the placebo group immediately after exercise (p < 0.05). The increase of CSA in the EPA group was significantly smaller than that in the placebo group immediately after exercise (p < 0.05). CONCLUSIONS: The present study suggests that the reduction of muscle work output caused by 30 CONs can be attenuated by an 8-week EPA and DHA supplementation. In addition, EPA and DHA supplementation can cause inhibition for reduction of ROM and increase of CSA after CONs.

Capsaicin supplementation increases time to exhaustion in high-intensity intermittent exercise without modifying metabolic responses in physically active men.

PURPOSE: The purpose of this study was to investigate the acute effect of capsaicin supplementation on performance and physiological responses during high-intensity intermittent exercise (HIIE). METHOD: Thirteen physically active men (age = 24.4 ± 4.0 years; height = 176.4 ± 6.9 cm; body mass = 78.7 ± 13.8 kg; running training per week = 3.9 ± 0.9 h) performed an incremental running test to determine peak oxygen uptake ([Formula: see text]) and the speed associated with [Formula: see text] (s[Formula: see text]). Thereafter, subjects completed two randomized, double-blind HIIE (15s:15 s at 120% s[Formula: see text]) trials 45-min after consuming capsaicin (12 mg) or an isocaloric placebo. Time to exhaustion, blood lactate concentration, oxygen consumption during and 20 min post-exercise, energy expenditure, time spent above 90% of [Formula: see text], and the rate of perceived exertion were evaluated. RESULTS: There was no difference between capsaicin and placebo for any variable except time to exhaustion [capsaicin: 1530 ± 515 s (102 efforts) vs placebo: 1342 ± 446 s (89 efforts); p < 0.001]. CONCLUSION: In conclusion, capsaicin supplementation increased time to exhaustion in high-intensity intermittent exercise without modifying the metabolic response of exercise or the rate of perceived exertion in physically active men. Capsaicin could be used to increase the training load during specific exercise training sessions.

The Effect of 1600 µg Inhaled Salbutamol Administration on 30 m Sprint Performance Pre and Post a Yo-Yo Intermittent Running Test in Football Players.

The purpose of the study was to investigate the effect of inhaling 1600 µg of salbutamol (SAL) on 30 m sprint before and after the Yo-Yo Intermittent Recovery test. In a randomised cross over single blind study 13 male non-asthmatic, football players volunteered (mean ± SD; age 18.1 ± 0.9 years; weight 69.5 ± 8.3 kg; height 1.78 ± 0.07 m). Participants completed two visits and were randomly assigned to either (SAL) or (PLA) treatment and performed a set of three sprints of 30 m before and after the Yo-Yo Intermittent Recovery Test (Yo-Yo IRT). Best sprint and mean sprint were analysed in addition to the distance covered during the Yo-Yo IRT; rating of perceived exertion and heart rate were collected at the end of each level completed. Repeated measures ANOVA were performed to investigate changes in performance between groups. Following the inhalation of supra-therapeutic salbutamol dose (1600 µg) neither 30 m sprint time (PLA 4.43 ± 0.14 s; SAL 4.44 ± 0.15 s, p = 0.76) nor distance covered in the Yo-Yo IRT test reported significant variation between PLA conditions (1660 ± 217 m) and SAL (1610 ± 229 m, p = 0.16). Moreover, lactate values, heart rate and RPE did not differ significantly between groups. The inhalation of 1600 µg salbutamol does not enhance 30 m sprint performance in non-fatigued and fatigue conditions. Our findings suggest when football players acutely inhale double the permitted dose of salbutamol, as indicated in the World Anti-Doping Agency List of Prohibited Substances and Methods, they will not experience improvements in sprint or endurance performance.

Effect of nicotine on repeated bouts of anaerobic exercise in nicotine naïve individuals.

PURPOSE: Nicotine is a psychostimulant that is reported to be commonly supplemented by athletes. The purpose of the current study was to determine the effects of a rapidly absorbed form of nicotine on repeated bouts of anaerobic exercise, perception of exertion and a range of cardiovascular variables while monitoring side effect profiles. METHODS: Sixteen healthy, nicotine naïve male athletes (24.1 ± 5.3 years, 179.0 ± 8.8 cm, 81.7 ± 13.5 kg, BMI 25.5 ± 3.0, Body fat% 13.2 ± 5.1%) completed two repeated 30 s Wingate tests with 3 min rest between bouts following consumption of either a 5-mg oral-dispersible nicotine strip (NIC) or a flavour-matched placebo (PLA) in a randomised, double-blind, cross-over design. Before the Wingate test, resting heart rate and blood pressure were also measured prior to and following PLA and NIC ingestion. RESULTS: Peak and average power output were significantly greater following NIC administration compared to PLA (P < 0.01). Similarly, significant increases were also seen in heart rate and blood pressure following NIC administration compared to PLA (P < 0.01). No significant effect on pre-exercise side effect score, reaction time, rate of perceived exertion or post exercise blood lactate levels were observed (P > 0.05). CONCLUSIONS: It was concluded that oral-dispersible nicotine strips increase repeated anaerobic performance, possibly through strong sympathetic stimulation, as evident by significant elevation of cardiovascular parameters.

Acute Capsaicin Supplementation Improves 1,500-m Running Time-Trial Performance and Rate of Perceived Exertion in Physically Active Adults.

de Freitas, MC, Cholewa, JM, Gobbo, LA, de Oliveira, JVNS, Lira, FS, and Rossi, FE. Acute capsaicin supplementation improves 1,500-m running time-trial performance and rate of perceived exertion in physically active adults. J Strength Cond Res 32(2): 572-577, 2018-The purpose of this study was to investigate the acute effect of capsaicin supplementation on performance, rate of perceived exertion (RPE), and blood lactate concentrations during short-duration running in physically active adults. Ten physically active men (age = 23.5 ± 1.9 years, mass = 78.3 ± 12.4 kg, and height = 177.9 ± 5.9 cm) completed 2 randomized, double-blind trials: Capsaicin condition (12 mg) or a placebo condition. Forty-five minutes after supplement consumption, the participants performed a 1,500-m running time trial. Time (in seconds) was recorded. Blood lactate concentration was analyzed at rest, immediately after exercise, after 5, 10, and 30 minutes during recovery and the RPE was collected after exercise. The time was significantly (t = 3.316, p = 0.009) lower in the capsaicin (371.6 ± 40.8 seconds) compared with placebo (376.7 ± 39 seconds). Rate of perceived exertion was significantly (t = 2.753, p = 0.022) less in the capsaicin (18.0 ± 1.9) compared with the placebo (18.8 ± 1.3). Lactate increased across time for both conditions without significant differences between (p > 0.05). In summary, acute capsaicin supplementation improves middle distance running (1,500 m) performance and reduced RPE in physically active adults.

Acute Capsaicin Supplementation Improves Resistance Training Performance in Trained Men.

Conrado de Freitas, M, Cholewa, JM, Freire, RV, Carmo, BA, Bottan, J, Bratfich, M, Della Bandeira, MP, Gonçalves, DC, Caperuto, EC, Lira, FS, and Rossi, FE. Acute capsaicin supplementation improves resistance training performance in trained men. J Strength Cond Res 32(8): 2227-2232, 2018-The purpose of this study was to investigate the acute effect of capsaicin supplementation on performance, rate of perceived exertion (RPE), and blood lactate concentrations during resistance exercise in healthy trained young men. Ten resistance-trained men (age = 22.7 ± 4.0 years, mass = 82.3 ± 9.6 kg, and height = 175 ± 0.1 cm) completed 2 randomized, double-blind trials: capsaicin condition (12 mg) or a placebo condition. Forty-five minutes after supplement consumption, subjects performed 4 sets until movement failure in the squat exercise at 70% of 1 repetition maximum with 90 seconds of rest interval between sets. The total mass lifted (total repetitions × mass lifted) was calculated. The RPE was recorded after the last set. Blood lactate was analyzed after each set of exercise, immediately postexercise, and after 3, 5, and at 30 minutes during recovery. The number of repetitions in each set decreased significantly after all sets compared with set-1 and after set-3 and set-4 in relation to set-2 (p < 0.001); however, total mass lifted was higher in capsaicin compared with placebo (3,919.4 ± 1,227.4 kg vs. 3,179.6 ± 942.4 kg, p = 0.002). Blood lactate increased significantly after each set (p < 0.001); however, there were no differences between conditions. Rate of perceived exertion was significantly less for the capsaicin condition than placebo (17.2 ± 1.0 vs. 18.3 ± 1.7, p = 0.048). In summary, acute capsaicin supplementation improves lower-body resistance training performance in trained young men.

Resveratrol improves exercise performance and skeletal muscle oxidative capacity in heart failure.

We investigated whether treatment of mice with established pressure overload-induced heart failure (HF) with the naturally occurring polyphenol resveratrol could improve functional symptoms of clinical HF such as fatigue and exercise intolerance. C57Bl/6N mice were subjected to either sham or transverse aortic constriction surgery to induce HF. Three weeks postsurgery, a cohort of mice with established HF (%ejection fraction <45) was administered resveratrol (~450 mg·kg-1·day-1) or vehicle for 2 wk. Although the percent ejection fraction was similar between both groups of HF mice, those mice treated with resveratrol had increased total physical activity levels and exercise capacity. Resveratrol treatment was associated with altered gut microbiota composition, increased skeletal muscle insulin sensitivity, a switch toward greater whole body glucose utilization, and increased basal metabolic rates. Although muscle mass and strength were not different between groups, mice with HF had significant declines in basal and ADP-stimulated O2 consumption in isolated skeletal muscle fibers compared with sham mice, which was completely normalized by resveratrol treatment. Overall, resveratrol treatment of mice with established HF enhances exercise performance, which is associated with alterations in whole body and skeletal muscle energy metabolism. Thus, our preclinical data suggest that resveratrol supplementation may effectively improve fatigue and exercise intolerance in HF patients.NEW & NOTEWORTHY Resveratrol treatment of mice with heart failure leads to enhanced exercise performance that is associated with altered gut microbiota composition, increased whole body glucose utilization, and enhanced skeletal muscle metabolism and function. Together, these preclinical data suggest that resveratrol supplementation may effectively improve fatigue and exercise intolerance in heart failure via these mechanisms.

Low-carbohydrate diet induces metabolic depression: a possible mechanism to conserve glycogen.

Long-term studies have found that low-carbohydrate diets are more effective for weight loss than calorie-restricted diets in the short term but equally or only marginally more effective in the long term. Low-carbohydrate diets have been linked to reduced glycogen stores and increased feelings of fatigue. We propose that reduced physical activity in response to lowered glycogen explains the diminishing weight loss advantage of low-carbohydrate compared with low-calorie diets over longer time periods. We explored this possibility by feeding adult Drosophila melanogaster a standard or a low-carbohydrate diet for 9 days and measured changes in metabolic rate, glycogen stores, activity, and body mass. We hypothesized that a low-carbohydrate diet would cause a reduction in glycogen stores, which recover over time, a reduction in physical activity, and an increase in resting metabolic rate. The low-carbohydrate diet reduced glycogen stores, which recovered over time. Activity was unaffected by diet, but metabolic rate was reduced, in the low-carbohydrate group. We conclude that metabolic depression could explain the decreased effectiveness of low-carbohydrate diets over time and recommend further investigation of long-term metabolic effects of dietary interventions and a greater focus on physiological plasticity within the study of human nutrition.

Lithium ameliorates sleep deprivation-induced mania-like behavior, hypothalamic-pituitary-adrenal (HPA) axis alterations, oxidative stress and elevations of cytokine concentrations in the brain and serum of mice.

OBJECTIVES: The goal of the present study was to investigate the effects of lithium administration on behavior, oxidative stress parameters and cytokine levels in the periphery and brain of mice subjected to an animal model of mania induced by paradoxical sleep deprivation (PSD). METHODS: Male C57 mice were treated with saline or lithium for 7 days. The sleep deprivation protocol started on the 5th day during for the last 36 hours of the treatment period. Immediately after the sleep deprivation protocol, animals locomotor activity was evaluated and serum and brain samples was extracted to evaluation of corticosterone and adrenocorticotropic hormone circulating levels, oxidative stress parameters and citokynes levels. RESULTS: The results showed that PSD induced hyperactivity in mice, which is considered a mania-like behavior. PSD increased lipid peroxidation and oxidative damage to DNA, as well as causing alterations to antioxidant enzymes in the frontal cortex, hippocampus and serum of mice. In addition, PSD increased the levels of cytokines in the brains of mice. Treatment with lithium prevented the mania-like behavior, oxidative damage and cytokine alterations induced by PSD. CONCLUSIONS: Improving our understanding of oxidative damage in biomolecules, antioxidant mechanisms and the inflammatory system - alterations presented in the animal models of mania - is important in helping us to improve our knowledge concerning the pathophysiology of BD, and the mechanisms of action employed by mood stabilizers.

Oral L-menthol reduces thermal sensation, increases work-rate and extends time to exhaustion, in the heat at a fixed rating of perceived exertion.

PURPOSE: The study investigated the effect of a non-thermal cooling agent, L-menthol, on exercise at a fixed subjective rating of perceived exertion (RPE) in a hot environment. METHOD: Eight male participants completed two trials at an exercise intensity between 'hard' and 'very hard', equating to 16 on the RPE scale at ~35 °C. Participants were instructed to continually adjust their power output to maintain an RPE of 16 throughout the exercise trial, stopping once power output had fallen by 30%. In a randomized crossover design, either L-menthol or placebo mouthwash was administered prior to exercise and at 10 min intervals. Power output, [Formula: see text]O2, heart rate, core and skin temperature was monitored, alongside thermal sensation and thermal comfort. Isokinetic peak power sprints were conducted prior to and immediately after the fixed RPE trial. RESULTS: Exercise time was greater (23:23 ± 3:36 vs. 21:44 ± 2:32 min; P = 0.049) and average power output increased (173 ± 24 vs. 167 ± 24 W; P = 0.044) in the L-menthol condition. Peak isokinetic sprint power declined from pre-post trial in the L-menthol l (9.0%; P = 0.015) but not in the placebo condition (3.4%; P = 0.275). Thermal sensation was lower in the L-menthol condition (P = 0.036), despite no changes in skin or core temperature (P > 0.05). CONCLUSION: These results indicate that a non-thermal cooling mouth rinse lowered thermal sensation, resulting in an elevated work rate, which extended exercise time in the heat at a fixed RPE.

Effects of Energy Drinks on Economy and Cardiovascular Measures.

Peveler, WW, Sanders, GJ, Marczinski, CA, and Holmer, B. Effects of energy drinks on economy and cardiovascular measures. J Strength Cond Res 31(4): 882-887, 2017-The use of energy drinks among athletes has risen greatly. Caffeine and taurine are the 2 primary performance enhancing ingredients found in energy drinks. The number of emergency department visits involving energy drinks doubled over the past 5 years. Reviews of the health complications have highlighted adverse cardiovascular events. The literature reveals that caffeine is known to moderately increase blood pressure (BP) and heart rate (HR). The purpose of this study was to determine the effect of 3 different energy drinks on cardiovascular and performance measures. Fifteen recreational runners completed 5 trials. The first trial consisted of a graded exercise protocol. The 4 remaining trials consisted of 15-minute economy trials at a treadmill speed consistent with 70% of subject's V[Combining Dot Above]O2max. An hour before subjects ingested 1 of the 3 energy drinks or a placebo. HR, BP, V[Combining Dot Above]O2, and rating of perceived exertion (RPE) were recorded during the 15-minute trial. Mean values for dependent measures were compared using repeated-measures analysis of variance. Fifteen-minute systolic BP readings were significantly lower in the placebo trials (156.93 ± 15.50) in relation to the 3 energy drink trials (163.87 ± 13.30, 166.47 ± 13.71, and 165.00 ± 15.23). There were no significant differences in diastolic BP and HR. There were no significant differences found in V[Combining Dot Above]O2 or RPE measures. Ingestion of energy drinks demonstrated no change in V[Combining Dot Above]O2 or RPE during the economy trials. The findings show no performance benefits under the conditions of this study. However, there does appear to be a significant increase in systolic BP.

In Vitro Antioxidant Activity and In Vivo Anti-Fatigue Effect of Sea Horse (Hippocampus) Peptides.

This study investigated changes the in vitro antioxidant activity of Hippocampus polypeptides during enzymatic hydrolysis, including the effects of enzyme species, enzyme concentration, material-liquid ratio, hydrolysis time, pH, and temperature of the reaction system. Its in vivo anti-fatigue activity was also studied. Hippocampus peptide prepared by papain digestion exhibited the highest 1,1-diphenyl-2-picryl-hydrazyl free radical scavenging rate (71.89% ± 1.50%) and strong hydroxyl radical scavenging rate (75.53% ± 0.98%), compared to those prepared by five other commonly used enzymes (i.e., trypsin, neutral protease, compound protease, flavorzyme, and alkaline protease). Additionally, maximum antioxidant activity of Hippocampus polypeptide prepared by papain digestion was reached after hydrolysis for 40 min at pH 6.0 and 60 °C of the reaction system by using 2000 U/g enzyme and a material-liquid ratio of 1:15. Moreover, compared with the control group, Hippocampus peptide prolonged the swimming time by 33%-40%, stabilized the blood glucose concentration, increased liver glycogen levels, and decreased blood lactate levels and blood urea nitrogen levels in mice (p < 0.01). In conclusion, these results indicated that Hippocampus polypeptide prepared by papain digestion under optimal conditions exhibited high degrees of antioxidant and anti-fatigue activity.

Guasha improves the rating of perceived exertion scale score and reduces heart rate variability in male weightlifters: a randomized controlled trial.

OBJECTIVE: To evaluate the effects of Guasha therapy on the rating of perceived exertion (RPE) scale score, and heart rate variability (HRV). METHODS: A randomized controlled trial of Guasha (skin scraping) was compared with a sham scraping group and control group. Sixteen sessions within an 8-week period were completed. Sixty-five male weightlifters who had undergone normal weightlifting training for a mean of 5 years before study commencement were recruited. The RPE scale score of "snatch", "clean and jerk" maneuvers (85% of one-repetition maximum), and HRV were measured before and after the intervention. RESULTS: The RPE scale score for snatch, clean and jerk were reduced significantly after intervention in the Guasha group and sham group. However, there was a significant difference in the low frequency (LF) domain and LF/high frequency (HF) ratio (P < 0.05): the LF domain decreased, and the LF/HF ratio decreased. CONCLUSION: Guasha could be used to reduce the RPE scale score, and increase the response to HRV. Guasha could be considered as an alternative to some types of recovery from sports training.