Effects of Preferred vs. Nonpreferred Music on Resistance Exercise Performance.

ABSTRACT: Ballmann, CG, McCullum, MJ, Rogers, RR, Marshall, MR , and Williams, TD. Effects of preferred vs. nonpreferred music on resistance exercise performance. J Strength Cond Res 35(6): 1650-1655, 2021-The purpose of this study was to examine the effects of listening to preferred vs. nonpreferred music on resistance exercise performance. Twelve resistance-trained college-aged males (age = 20.5 ± 1.24 years, height = 183.9 ± 6.8 cm, and body mass = 97.0 ± 18.2 kg) were recruited for this study. In a within-groups counterbalanced study design, subjects either listened to preferred or nonpreferred music during a bench press exercise test. Subjects completed as many repetitions as possible at 75% of their 1 repetition maximum with maximum explosive intent. Power and velocity of the barbell movement was measured for the first 3 repetitions using a linear position transducer. Motivation was measured using a visual analog scale immediately after exercise. Each exercise trial was separated by a 48-hour washout period. Results indicate that listening to preferred music increased overall bench press repetitions completed (p = 0.005; effect size [ES] = 0.84). During the first 3 repetitions, mean velocity (p = 0.001; ES = 1.6), relative mean power (p = 0.012; ES = 0.55), peak velocity (p = 0.011; ES = 0.99), and peak power (p = 0.009; ES = 0.35) were higher while listening to preferred music vs. nonpreferred music. Finally, motivation during the lift (p < 0.001; ES = 5.9) was significantly higher while listening to preferred vs. nonpreferred music. Current findings suggest that listening to preferred music by the individual results in greater performance than nonpreferred during resistance exercise. Athletes may benefit from the option to listen to their preferred music to increase motivation and resistance exercise performance.

Effect of Acute Beetroot Juice Supplementation on Bench Press Power, Velocity, and Repetition Volume.

Williams, TD, Martin, MP, Mintz, JA, Rogers, RR, and Ballmann, CG. Effect of acute beetroot juice supplementation on bench press power, velocity, and repetition volume. J Strength Cond Res 34(4): 924-928, 2020-The purpose of this study was to examine the effects of acute beetroot juice (BRJ) supplementation on power, velocity, and repetitions to failure (RTF) during bench press exercise. Resistance-trained male subjects (n = 11) were recruited for this study. Using a double-blinded, counterbalanced, crossover study design, subjects were supplemented with either 70 ml of BRJ or placebo (PL; black currant juice) 2 hours before exercise. During each exercise trial, subjects began by completing 2 sets × 2 repetitions of bench press at 70% 1 repetition maximum (1RM) with maximum explosive intent. Barbell velocity and power were measured using a linear position transducer. Subjects then completed 3 sets × RTF at 70% 1RM separated by 2 minutes of rest between each set. Maximum mean power, velocity, and repetitions were analyzed. Mean velocity (p = 0.011; effect size [ES] = 0.54) and mean power (p = 0.015; ES = 0.51) were significantly higher with BRJ when compared with PL. Total RTF (p = 0.002; ES = 0.46) was higher during the BRJ condition vs. PL. Results indicate that acute BRJ supplementation positively impacts velocity, power, and total repetitions during free-weight bench press exercise.

Effects of short-term Rhodiola Rosea (Golden Root Extract) supplementation on anaerobic exercise performance.

The purpose of this study was to examine the effects of short-term Rhodiola Rosea (Golden Root Extract (GRE)) supplementation on repeated Wingate performance. Eleven physically active college aged females were recruited for this study. In a within groups counterbalanced study design, participants were supplemented with either 1,500 mg/day of GRE or placebo (gluten-free cornstarch) for 3 days. Participants also took an additional 500 mg dose of corresponding treatment 30 minutes prior to testing of each trial. During each exercise trial, participants completed 3 × 15-second Wingate Anaerobic Tests (WAnTs) separated by 2-minute active recovery periods. Each exercise trial was separated by a 7 day washout period. Over the 3 × 15-second WAnTs, mean watts (p = 0.017, ES = 0.55), mean anaerobic capacity (p = 0.025, ES = 0.96), mean anaerobic power (p = 0.03, ES = 1.07), mean peak watts (p = 0.029,ES = 0.46), and mean total work (p = 0.017, ES = 0.49) were higher in the GRE treatment trial versus placebo. However, mean fatigue index (p = 0.094, ES = 0.39) was unaffected regardless of treatment. Our results show that GRE supplementation enhanced anaerobic exercise performance as measured through repeated WAnTs. GRE may possess ergogenic benefits and findings hold important implications for boosting anaerobic performance in repeated anaerobic bouts of exercise.

Lifelong quercetin enrichment and cardioprotection in Mdx/Utrn+/- mice.

Duchenne Muscular Dystrophy (DMD) is associated with progressive cardiac pathology; however, the SIRT1/PGC1-α activator quercetin may cardioprotect dystrophic hearts. We tested the extent to which long-term 0.2% dietary quercetin enrichment attenuates dystrophic cardiopathology in Mdx/Utrn+/- mice. At 2 mo, Mdx/Utrn+/- mice were fed quercetin-enriched (Mdx/Utrn+/--Q) or control diet (Mdx/Utrn+/-) for 8 mo. Control C57BL/10 (C57) animals were fed a control diet for 10 mo. Cardiac function was quantified by MRI at 2 and 10 mo. Spontaneous physical activity was quantified during the last week of treatment. At 10 mo hearts were excised for histological and biochemical analysis. Quercetin feeding improved various physiological indexes of cardiac function in diseased animals. Mdx/Utrn+/--Q also engaged in more high-intensity physical activity than controls. Histological analyses of heart tissues revealed higher expression and colocalization of utrophin and α-sarcoglycan. Lower abundance of fibronectin, cardiac damage (Hematoxylin Eosin-Y), and MMP9 were observed in quercetin-fed vs. control Mdx/Utrn+/- mice. Quercetin evoked higher protein abundance of PGC-1α, cytochrome c, ETC complexes I-V, citrate synthase, SOD2, and GPX compared with control-fed Mdx/Utrn+/- Quercetin decreased abundance of inflammatory markers including NFκB, TGF-ß1, and F4/80 compared with Mdx/Utrn+/-; however, P-NFκB, P-IKBα, IKBα, CD64, and COX2 were similar between groups. Dietary quercetin enrichment improves cardiac function in aged Mdx/Utrn+/- mice and increases mitochondrial protein content and dystrophin glycoprotein complex formation. Histological analyses indicate a marked attenuation in pathological cardiac remodeling and indicate that long-term quercetin consumption benefits the dystrophic heart. NEW & NOTEWORTHY: The current investigation provides first-time evidence that quercetin provides physiological cardioprotection against dystrophic pathology and is associated with improved spontaneous physical activity. Secondary findings suggest that quercetin-dependent outcomes are in part due to PGC-1α pathway activation.

Long-term dietary quercetin enrichment as a cardioprotective countermeasure in mdx mice.

NEW FINDINGS: What is the central question of this study? The central question of this study is to understand whether dietary quercetin enrichment attenuates physiologic, histological, and biochemical indices of cardiac pathology. What is the main finding and its importance? Novel findings from this investigation, in comparison to prior published studies, suggest that mouse strain-dependent cardiac outcomes in performance and remodelling exist. Unlike Mdx/Utrn-/+ mice, mdx mice receiving lifelong quercetin treatment did not exhibit improvements cardiac function. Similar to prior work in Mdx/Utrn-/+ mice, histological evidence of remodelling suggests that quercetin consumption may have benefited hearts of mdx mice. Positive outcomes may be related to indirect markers that suggest improved mitochondrial wellbeing and to selected indices of inflammation that were lower in hearts from quercetin-fed mice. Duchenne muscular dystrophy causes a decline in cardiac health, resulting in premature mortality. As a potential countermeasure, quercetin is a polyphenol possessing inherent anti-inflammatory and antioxidant effects that activate proliferator-activated γ coactivator 1α (PGC-1α), increasing the abundance of mitochondrial biogenesis proteins. We investigated the extent to which lifelong 0.2% dietary quercetin enrichment attenuates dystrophic cardiopathology in mdx mice. Dystrophic animals were fed a quercetin-enriched or control diet for 12 months, while control C57 mice were fed a control diet. Cardiac function was assessed via 7 T magnetic resonance imaging at 2, 10 and 14 months. At 14 months, hearts were harvested for histology and Western blotting. The results indicated an mdx strain-dependent decline in cardiac performance at 14 months and that dietary quercetin enrichment did not attenuate functional losses. In contrast, histological analyses provided evidence that quercetin feeding was associated with decreased fibronectin and indirect damage indices (Haematoxylin and Eosin) compared with untreated mdx mice. Dietary quercetin enrichment increased cardiac protein abundance of PGC-1α, cytochrome c, electron transport chain complexes I-V, citrate synthase, superoxide dismutase 2 and glutathione peroxidase (GPX) versus untreated mdx mice. The protein abundance of the inflammatory markers nuclear factor-κB, phosphorylated nuclear factor kappa beta (P-NFκB) and phosphorylated nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha (P-IKBα) was decreased by quercetin compared with untreated mdx mice, while preserving nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor alpha( IKBα) compared with mdx mice. Furthermore, quercetin decreased transforming growth factor-ß1, cyclooxygenase-2 (COX2) and macrophage-restricted F4/80 protein (F4/80) versus untreated mdx mice. The data suggest that long-term quercetin enrichment does not impact physiological parameters of cardiac function but improves indices of mitochondrial biogenesis and antioxidant enzymes, facilitates dystrophin-associated glycoprotein complex (DGC) assembly and decreases inflammation in dystrophic hearts.

Oral quercetin administration transiently protects respiratory function in dystrophin-deficient mice.

KEY POINT: PGC-1α pathway activation has been shown to decrease disease severity and can be driven by quercetin. Oral quercetin supplementation protected respiratory function for 4-6 months during a 12 month dosing regimen. This transient protection was probably due to a failure to sustain elevated SIRT1 activity and downstream PGC-1α signalling. Quercetin supplementation may be a beneficial treatment as part of a cocktail provided continued SIRT1 activity elevation is achieved. ABSTRACT: Duchenne muscular dystrophy (DMD) impacts 1 : 3500 boys and leads to muscle dysfunction culminating in death due to respiratory or cardiac failure. There is an urgent need for effective therapies with the potential for immediate application for this patient population. Quercetin, a flavonoid with an outstanding safety profile, may provide therapeutic relief to DMD patients as the wait for additional therapies continues. This study evaluated the capacity of orally administered quercetin (0.2%) in 2 month old mdx mice to improve respiratory function and end-point functional and histological outcomes in the diaphragm following 12 months of treatment. Respiratory function was protected for the first 4-6 months of treatment but appeared to become insensitive to quercetin thereafter. Consistent with this, end-point functional measures were decreased and histopathological measures were more severe in dystrophic muscle compared to C57 and similar between control-fed and quercetin-fed mdx mice. To better understand the transient nature of improved respiratory function, we measured PGC-1α pathway activity, which is suggested to be up-regulated by quercetin supplementation. This pathway was largely suppressed in dystrophic muscle compared to healthy muscle, and at the 14 month time point dietary quercetin enrichment did not increase expression of downstream effectors. These data support the efficacy of quercetin as an intervention for DMD in skeletal muscle, and also indicate the development of age-dependent quercetin insensitivity when continued supplementation fails to drive the PGC-1α pathway. Continued study is needed to determine if this is related to disease severity, age or other factors.

Adult expression of PGC-1α and -1ß in skeletal muscle is not required for endurance exercise-induced enhancement of exercise capacity.

Exercise has been shown to be the best intervention in the treatment of many diseases. Many of the benefits of exercise are mediated by adaptions induced in skeletal muscle. The peroxisome proliferator-activated receptor gamma coactivator-1 (PGC-1) family of transcriptional coactivators has emerged as being key mediators of the exercise response and is considered to be essential for many of the adaptions seen in skeletal muscle. However, the contribution of the PGC-1s in skeletal muscle has been evaluated by the use of either whole body or congenital skeletal muscle-specific deletion. In these models, PGC-1s were never present, thereby opening the possibility to developmental compensation. Therefore, we generated an inducible muscle-specific deletion of PGC-1α and -1ß (iMyo-PGC-1DKO), in which both PGC-1α and -ß can be deleted specifically in adult skeletal muscle. These iMyo-PGC-1DKO animals were used to assess the role of both PGC-1α and -1ß in adult skeletal muscle and their contribution to the exercise training response. Untrained iMyo-PGC-1DKO animals exhibited a time-dependent decrease in exercise performance 8 wk postdeletion, similar to what was observed in the congenital muscle-specific PGC-1DKOs. However, after 4 wk of voluntary training, the iMyo-PGC-1DKOs exhibited an increase in exercise performance with a similar adaptive response compared with control animals. This increase was associated with an increase in electron transport complex (ETC) expression and activity in the absence of PGC-1α and -1ß expression. Taken together these data suggest that PGC-1α and -1ß expression are not required for training-induced exercise performance, highlighting the contribution of PGC-1-independent mechanisms.

Graded hypoxia and blood oxidative stress during exercise recovery.

Altitude exposure and exercise elicit oxidative stress in blood; however, exercise recovery at 5000 m attenuates oxidative stress. The purpose was to determine the altitude threshold at which blood oxidative stress is blunted during exercise recovery. Twelve males 18-28 years performed four-cycle ergometry bouts (60 min, 70% VO2max, at 975 m). In a randomised counterbalanced crossover design, participants recovered 6 h at 0, 1667, 3333 and 5000 m in a normobaric hypoxia chamber (recovery altitudes were simulated by using a computerised system in an environmental chamber by lowering the partial pressure of oxygen to match that of the respective altitude). Oxygen saturation was monitored throughout exercise recovery. Blood samples obtained pre-, post-, 1 h post- and 5 h post-exercise were assayed for ferric-reducing antioxidant plasma, Trolox equivalent antioxidant capacity, uric acid, lipid hydroperoxides and protein carbonyls. Muscle biopsies obtained pre and 6 h were analysed by real-time polymerase chain reaction to quantify expression of hemeoxgenase 1, superoxide dismutase 2 and nuclear factor (euthyroid-derived 2)-like factor. Pulse oximetry data were similar during exercise, but decreased for the three highest recovery elevations (0 m = 0%, 1667 m = -3%; 3333 m = -7%; 5000 m = -17%). A time-dependent oxidative stress occurred following exercise for all variables, but the two highest recovery altitudes partially attenuated the lipid hydroperoxide response (0 m = +135%, 1667 m = +251%, 3333 m = +99%; 5000 m = +108%). Data may indicate an altitude threshold between 1667 and 3333 m, above which the oxidative stress response is blunted during exercise recovery.

Interleukin-6 mediates exercise preconditioning against myocardial ischemia reperfusion injury.

Interleukin-6 (IL-6) is a pleiotropic cytokine that protects against cardiac ischemia-reperfusion (I/R) injury following pharmacological and ischemic preconditioning (IPC), but the affiliated role in exercise preconditioning is unknown. Our study purpose was to characterize exercise-induced IL-6 cardiac signaling (aim 1) and evaluate myocardial preconditioning (aim 2). In aim 1, C57 and IL-6(-/-) mice underwent 3 days of treadmill exercise for 60 min/day at 18 m/min. Serum, gastrocnemius, and heart were collected preexercise, immediately postxercise, and 30 and 60 min following the final exercise session and analyzed for indexes of IL-6 signaling. For aim 2, a separate cohort of exercise-preconditioned (C57 EX and IL-6(-/-) EX) and sedentary (C57 SED and IL-6(-/-) SED) mice received surgical I/R injury (30 min I, 120 min R) or a time-matched sham operation. Ischemic and perfused tissues were examined for necrosis, apoptosis, and autophagy. In aim 1, serum IL-6 and IL-6 receptor (IL-6R), gastrocnemius, and myocardial IL-6R were increased following exercise in C57 mice only. Phosphorylated (p) signal transducer and activator of transcription 3 was increased in gastrocnemius and heart in C57 and IL-6(-/-) mice postexercise, whereas myocardial iNOS and cyclooxygenase-2 were unchanged in the exercised myocardium. Exercise protected C57 EX mice against I/R-induced arrhythmias and necrosis, whereas arrhythmia score and infarct outcomes were higher in C57 SED, IL-6(-/-) SED, and IL-6(-/-) EX mice compared with SH. C57 EX mice expressed increased p-p44/42 MAPK (Thr(202)/Tyr(204)) and p-p38 MAPK (Thr(180)/Tyr(182)) compared with IL-6(-/-) EX mice, suggesting pathway involvement in exercise preconditioning. Findings indicate exercise exerts cardioprotection via IL-6 and strongly implicates protective signaling originating from the exercised skeletal muscle.

Histological and biochemical outcomes of cardiac pathology in mdx mice with dietary quercetin enrichment.

NEW FINDINGS: What is the central question of this study? Does dietary quercetin enrichment improve biochemical and histological outcomes in hearts from mdx mice? What is the main finding and what is its importance? Biochemical and histological findings suggest that chronic quercetin feeding of mdx mice may improve mitochondrial function and attenuate tissue pathology. Patients with Duchenne muscular dystrophy suffer from cardiac pathology, which causes up to 40% of all deaths because of fibrosis and cardiac complications. Quercetin is a flavonol with anti-inflammatory and antioxidant effects and is also an activator of peroxisome proliferator-activated receptor γ coactivator 1α capable of antioxidant upregulation, mitochondrial biogenesis and prevention of cardiac complications. We sought to determine the extent to which dietary quercetin enrichment prevents (experiment 1) and rescues cardiac pathology (experiment 2) in mdx mice. In experiment 1, 3-week-old mdx mice were fed control chow (C3w6m, n = 10) or chow containing 0.2% quercetin for 6 months (Q3w6m, n = 10). In experiment 2, 3-month-old mdx mice were fed control chow (C3m6m, n = 10) or 0.2% chow containing 0.2% quercetin for 6 months (Q3m6m, n = 10). Hearts were excised for histological and biochemical analyses. In experiment 1, Western blot targets for mitochondrial biogenesis (cytochrome c, P = 0.007) and antioxidant expression (superoxide dismutase 2, P = 0.014) increased in Q3w6m mice compared with C3w6m. Histology revealed increased utrophin (P = 0.025) and decreased matrix metalloproteinase 9 abundance (P = 0.040) in Q3w6m mice compared with C3w6m. In experiment 2, relative (P = 0.023) and absolute heart weights (P = 0.020) decreased in Q3m6m mice compared with C3m6m. Indications of damage (Haematoxylin- and Eosin-stained sections, P = 0.007) and Western blot analysis of transforming growth factor ß1 (P = 0.009) were decreased in Q3m6m mice. Six months of quercetin feeding increased a mitochondrial biomarker, antioxidant protein and utrophin and decreased matrix metalloproteinase 9 in young mice. Given that these adaptations are associated with attenuated cardiac pathology and damage, the present findings may indicate that dietary quercetin enrichment attenuates dystrophic cardiac pathology, but physiological confirmation is needed.

Involvement of the δ-opioid receptor in exercise-induced cardioprotection.

NEW FINDINGS: What is the central question of this study? Does the δ-opioid receptor trigger exercise-induced cardioprotection against ischaemia-reperfusion injury? What is the main finding and its importance? In exercised hearts, the δ-opioid receptor appears to trigger cardioprotection against ischaemia-reperfusion-induced tissue necrosis but not apoptosis. ABSTRACT: Endogenous opioids mediate exercise-induced cardioprotection against ischaemia-reperfusion (IR) injury, although the opioid receptor subtype mediating this effect is unknown. We investigated whether the δ-opioid receptor mediates exercise-induced cardioprotection against IR injury. Endogenous opioids are produced in various tissues, including the heart and skeletal muscle; therefore, we also sought to identify the effect of exercise on circulating endogenous opioid as well as transcript, protein and receptor expression in heart and skeletal muscle. Male Sprague-Dawley rats (n = 73) were assigned randomly to treadmill exercise or sedentary treatments. Cardiac tissue and serum were harvested 0, 20 and 120 min following exercise and from sedentary animals (n = 32) to quantify effects on proenkephalin and δ-opioid receptor mRNA and protein levels, as well as serum enkephalin. Skeletal muscle (soleus) was harvested at identical time points for determination of proenkephalin protein and mRNA. A separate group of rats (n = 41) were randomly assigned to sham operation (Sham; surgical control), sedentary (Sed), exercise (Ex) or exercise + Î´-opioid receptor antagonist (ExD; naltrindole, 5 mg kg(-1) i.p.) and received IR by left anterior descending coronary artery ligation in vivo. After IR, tissues were harvested to quantify treatment effects on necrosis and apoptosis. Cardiac proenkephalin mRNA expression increased following exercise (0 min, P = 0.03; 120 min, P = 0.021), while soleus expression was unaffected. Exercise-induced changes in serum enkephalin were undetectable. After IR, tissue necrosis was elevated in Sed and ExD hearts (P < 0.001 and P = 0.003, respectively) compared with the Sham group, while the Ex group was partly protected. After IR, apoptosis was evident in Sed hearts (P = 0.016), while Ex and ExD hearts were protected. Data suggest that cardioprotective opioids are produced by the heart, but not by the soleus. After IR, the δ-opioid receptor may mediate, in part, cardioprotection against necrosis but not apoptosis.

Exercise-induced oxidative stress and hypoxic exercise recovery.

Hypoxia due to altitude diminishes performance and alters exercise oxidative stress responses. While oxidative stress and exercise are well studied, the independent impact of hypoxia on exercise recovery remains unknown. Accordingly, we investigated hypoxic recovery effects on post-exercise oxidative stress. Physically active males (n = 12) performed normoxic cycle ergometer exercise consisting of ten high:low intensity intervals, 20 min at moderate intensity, and 6 h recovery at 975 m (normoxic) or simulated 5,000 m (hypoxic chamber) in a randomized counter-balanced cross-over design. Oxygen saturation was monitored via finger pulse oximetry. Blood plasma obtained pre- (Pre), post- (Post), 2 h post- (2Hr), 4 h post- (4Hr), and 6 h (6Hr) post-exercise was assayed for Ferric Reducing Ability of Plasma (FRAP), Trolox Equivalent Antioxidant Capacity (TEAC), Lipid Hydroperoxides (LOOH), and Protein Carbonyls (PC). Biopsies from the vastus lateralis obtained Pre and 6Hr were analyzed by real-time PCR quantify expression of Heme oxygenase 1 (HMOX1), Superoxide Dismutase 2 (SOD2), and Nuclear factor (euthyroid-derived2)-like factor (NFE2L2). PCs were not altered between trials, but a time effect (13 % Post-2Hr increase, p = 0.044) indicated exercise-induced blood oxidative stress. Plasma LOOH revealed only a time effect (p = 0.041), including a 120 % Post-4Hr increase. TEAC values were elevated in normoxic recovery versus hypoxic recovery. FRAP values were higher 6Hr (p = 0.045) in normoxic versus hypoxic recovery. Exercise elevated gene expression of NFE2L2 (20 % increase, p = 0.001) and SOD2 (42 % increase, p = 0.003), but hypoxic recovery abolished this response. Data indicate that recovery in a hypoxic environment, independent of exercise, may alter exercise adaptations to oxidative stress and metabolism.

Acute hypoxia and exercise-induced blood oxidative stress.

Hypoxic exercise is characterized by workloads decrements. Because exercise and high altitude independently elicit redox perturbations, the study purpose was to examine hypoxic and normoxic steady-state exercise on blood oxidative stress. Active males (n = 11) completed graded cycle ergometry in normoxic (975 m) and hypoxic (3,000 m) simulated environments before programing subsequent matched intensity or workload steady-state trials. In a randomized counterbalanced crossover design, participants completed three 60-min exercise bouts to investigate the effects of hypoxia and exercise intensity on blood oxidative stress. Exercise conditions were paired as such; 60% normoxic VO(2)peak performed in a normoxic environment (normoxic intensity-normoxic environment, NI-NE), 60% hypoxic VO(2)peak performed in a normoxic environment (HI-NE), and 60% hypoxic VO(2)peak performed in a hypoxic environment (HI-HE). Blood plasma samples drawn pre (Pre), 0 (Post), 2 (2HR) and 4 (4HR) hr post exercise were analyzed for oxidative stress biomarkers including ferric reducing ability of plasma (FRAP), trolox equivalent antioxidant capacity (TEAC), lipid hydroperoxides (LOOH) and protein carbonyls (PCs). Repeated-measures ANOVA were performed, a priori significance of p ≤ .05. Oxygen saturation during the HI-HE trial was lower than NI-NE and HI-NE (p < .05). A Time × Trial interaction was present for LOOH (p = .013). In the HI-HE trial, LOOH were elevated for all time points post while PC (time; p = .001) decreased post exercise. As evidenced by the decrease in absolute workload during hypoxic VO(2)peak and LOOH increased during HI-HE versus normoxic exercise of equal absolute (HI-NE) and relative (NI-NE) intensities. Results suggest acute hypoxia elicits work decrements associated with post exercise oxidative stress.

American Football Headgear Impairs Visuomotor Drill Performance in Division I NCAA Football Athletes.

Background/Objectives: Previous evidence has shown that American football headgear (e.g., facemasks, visors/eye shields) differentially impairs reaction time (RT) to visual stimuli, most notably in peripheral fields of view. However, this has only been established with stationary RT testing, which may not translate to gameplay situations that require gross motor skills. Therefore, the purpose of this study was to build upon previous findings to elucidate the effects of various American football headgear on gross motor visuomotor drill performance. Methods: Division 1 NCAA football players (n = 16) with normal/corrected-to-normal vision participated and completed two experiments (EXP), each with differing conditions: EXP1- Varying facemask reinforcement and EXP2- Varying visor/eye shield light transmittance. In EXP1, participants completed an agility test for the following conditions: baseline/no helmet (BL), helmet + light (HL), helmet + medium (HM), and helmet + heavy (HH) face mask reinforcement. In EXP2, participants completed an agility test for the following conditions: baseline/no helmet (BL), helmet + clear visor (HCV), helmet + smoke-tinted visor (HSV), and helmet + mirrored visor (HMV). For each condition in EXP1 and EXP2, participants completed a reactive agility task using a FITLIGHT trainer system where five poles were equipped with a total of ten LED sensors and were placed in a semi-circle 1 m around a center point. Participants were asked to step and reach with their hands to hit each ten lights individually as fast as possible upon illumination. Each reactive agility test was repeated for a total of three attempts. Results: Average reaction time was analyzed and compared between conditions and according to visual fields of interest (e.g., central vs. peripheral). Results from EXP1 showed that compared to BL, reactive agility was worsened by HL (p = 0.030), HM (p = 0.034), and HH (p = 0.003) conditions. No differences between facemask conditions existed for overall performance (p > 0.05). For EXP2, HCV (p < 0.001), HSV (p < 0.001), and HMV (p < 0.001) conditions resulted in worsened reactive agility performance compared to BL. No differences between visor conditions existed for overall performance (p > 0.05). Conclusions: Overall, these findings suggest that American football headgear impairs reactive agility, which could result in worsened game performance and safety. Future studies investigating training strategies to overcome impairments are warranted.

F@#$ pain! A mini-review of the hypoalgesic effects of swearing.

Swearing, or the use of taboo language, has been repeatedly shown to induce hypoalgesia. While reliable hypoalgesic effects have been observed across studies, the mechanisms by which swearing influences pain and the optimal dosage of swearing remain poorly understood. Plausible mechanistic rationale for swearing's impact on pain include sympathetic response, emotion, humor, distraction, aggression, state disinhibition, psychological flow, risky behavior, and self-confidence. It remains unknown how the intensity of the swear word, speech volume, frequency, or timing influences pain modulation. While the majority of evidence demonstrates the efficacy of swearing at attenuating acute pain responses, these studies have utilized healthy populations with controlled experiments in laboratory settings. Comparatively, less is known about how laboratory findings translate practically/clinically to diverse populations, various dosages, and different pain chronicities. A greater understanding of mechanistic underpinnings and practical implications are necessary to feasibly implement swearing as a therapeutic modality to combat pain. The purpose of the following mini-review is to provide an overview of the current evidence on swearing for the reduction of pain, speculate on plausible underlying mechanisms, and discuss the potential for optimization of swearing for real-world translation. Lastly, identifying knowledge gaps to aid in directing future research will be discussed.

A Matter of Taste: Roles of Taste Preference on Performance and Psychological Responses during Anaerobic Exercise.

Various tastes including sweet, bitter, and sour have been shown to differentially influence physiological and psychological processes. Furthermore, ingestion of bitter and sweet solutions has been shown to acutely enhance exercise performance. However, the taste is highly individualized, and it is unclear if preference influences the ergogenic potential of taste. The purpose of this study was to investigate the effects of preferred and non-preferred drink tastes on anaerobic performance and psychological responses thereof. Physically active females participated in two counterbalanced sprint trials each with a different condition: (1) non-preferred taste (NPT), (2) Preferred taste (PT). Participants self-reported taste preferences (sweet, sour, bitter) with the highest-ranked taste being used for the PT condition and the lowest-ranked for NPT. For each visit, participants completed a 15 s Wingate Anaerobic Test (WAnT) prior to (PRE) ingestion of ~20 mL of their NP or PREF taste. Following ingestion, participants completed 2 min of active recovery, rated their taste preference of the solution, and completed another 15 s WAnT. The rate of perceived exertion (RPE), motivation, and enjoyment were measured through a visual analog scale following each WAnT. Anaerobic performance measures and heart rate (HR) were also obtained at the succession of each WAnT. Findings revealed no differences between taste conditions for mean power (p = 0.455), peak power (p = 0.824), or HR (p = 0.847). RPE was significantly lower with PT versus NPT (p = 0.006). Exercise enjoyment (p = 0.022) was higher with PT compared to NPT. NPT resulted in worse motivation compared to PRE (p = 0.001) while no changes were observed between PT and PRE (p = 0.197). These findings suggest that preferred drink taste may not enhance acute performance but improves psychological responses to maximal anaerobic exercise which may have implications for improving exercise training and adherence.

Ammonia Inhalants Enhance Psychophysiological Responses and Performance During Repeated High Intensity Exercise.

Purpose: Ammonia inhalants (NH3) are anecdotally used in competition by athletes for their purported stimulant effects. However, evidence on the efficacy of NH3 is conflicting, and little to no studies to date have investigated its effect on repeated exercise. The purpose of this study was to examine the effects of NH3 on psychophysiological responses and performance during repeated high-intensity exercise. Methods: In a counterbalanced crossover design, physically active females completed two repeated high-intensity sprint trials with a different treatment: Control (CON; water) or Ammonia Inhalants (NH3; 0.33 cc). For each trial, participants completed 3 × 15s Wingate anaerobic tests (WAnT) separated by 2 min of active recovery. Prior to each WAnT, participants took a single 3-s inhale of the corresponding treatment. After the succession of each WAnT, heart rate (HR) and rate of perceived exertion (RPE) were documented. Subjective feelings of alertness and "psyched up" energy were measured using a visual analog scale. Trials were separated by at least 48 hr. Results: The results indicate that over the WAnTs, mean power (p = .017) and peak power (p = .006) were significantly higher with NH3 compared to CON despite a lack of changes in fatigue index (p = .928). HR (p = .101) and RPE (p = .897) were not different with varying treatments. Perceived alertness (p = .010) and psyched-up energy (p = .002) were significantly higher with NH3 versus CON. Conclusion: These findings provide empirical support for the use of NH3 to improve repeated high-intensity exercise performance in females that may be underpinned by alterations in subjective alertness and energy.

Effects of caffeine consumption combined with listening to music during warm-up on taekwondo physical performance, perceived exertion and psychological aspects.

The effects of caffeine (CAF) and music have been well documented when used separately, but their combined effects are not yet studied. Thus, the present study assessed the acute effects of combining a low dose of CAF with listening to music during warm-up on taekwondo physical performance, perceived exertion (RPE), and psychological responses during taekwondo-specific tasks in male elite athletes. In a double-blinded, randomized, placebo-controlled crossover study design, male taekwondo athletes (n = 16; age: 18.25 ± 0.75 years) performed the taekwondo-specific agility test (TSAT), 10 s frequency speed of kick test (FSKT-10s) and the multiple version of FSKT (FSKT-mult) under the following conditions: 1) CAF without music (CAF+NoM), 2) placebo (PL) without music (PL+NoM), 3) CAF with music (CAF+M), 4) PL with music (PL+M), 5) no supplement with music (NoS+M) and no supplement without music (control). RPE, feeling scale (FS), felt arousal scale (FAS) and physical enjoyment (PACES) were determined after each test. Findings showed the CAF+M condition induced better performances than other conditions for TSAT, FSKT-10s, FSKT-mult, RPE, FAS and FS and PACES post FSKT-10s (all p<0.05). Moreover, CAF+M resulted in better responses than other conditions for PACES post TSAT (p<0.05) with the exception of CAF+NoM. Likewise, CAF+M condition induced better physical enjoyment than PL+NoM, NoS+M and PL+M conditions post FSKT-mult (p<0.05). Combining low dose of CAF with music during warm-up was an effective strategy that induced greater effects than their isolated use during taekwondo specific tasks.

The effects of pre-task music on exercise performance and associated psycho-physiological responses: a systematic review with multilevel meta-analysis of controlled studies.

This systematic review summarized the studies that examined the pre-task music effects on performance aspects and quantitatively analyzed their outcomes. A systematic search for controlled studies investigating the acute effects of pre-task music on physical performance, cognitive aspects and associated psycho-physiological responses was performed through Scopus, PubMed, Web of Science and Cochrane Library databases up to 17 May 2023, with thirty studies fulfilled the inclusion criteria. Data was analyzed using the robust multilevel meta-analysis model of standardized mean difference "SMD" with 95% confidence intervals (95%CI) and prediction intervals (PI) were reported. Pre-task music induced improvements of completion time (SMD = -0.24; 95% CI = -0.46 to -0.01; PI = -0.82 to 0.35; p = 0.04), relative mean power (RMP) (SMD = 0.38; 95% CI = 0.16 to 0.60; PI = -0.36 to 1.12; p = 0.003) and fatigue (SMD = -0.20; 95% CI = -0.32 to -0.09; PI = -0.36 to -0.05; p = 0.01), moderate effects on relative peak power (RPP) (SMD = 0.53; 95% CI = 0.21 to 0.85; PI = -0.42 to 1.48; p = 0.005), and high effect on feeling scale (FS) (SMD = 2.42; 95% CI = 0.52 to 4.31; PI = -11.43 to 16.26; p = 0.03). Greater benefits were recorded in jumping performance in males than females (p = 0.01), and for active than trained subjects for completion time (p = 0.02), RPP (p = 0.02) and RMP (p = 0.03). Larger benefits were obtained for FS post-warming up than after testing (p = 0.04). Self-selected music induced greater effects than pseudo- and pre-selected for performance decrement index (p = 0.05) and FS (p = 0.02). It could be concluded that pre-task music improved psychological responses and fatigue-related symptoms associated with exercise performance enhancement.

The Influence of Music Preference on Countermovement Jump and Maximal Isometric Performance in Active Females.

Previous studies have shown that listening to preferred music during resistance and endurance exercises improves performance. However, it is unknown if these phenomena translate to short-duration explosive exercises. The purpose of this study was to investigate the influences of preferred and non-preferred music on countermovement jump (CMJ) performance, isometric mid-thigh pull (IMTP), and psychological responses to music during explosive movements. Physically active females (age 18-25) volunteered to take part in the study. In a counterbalanced, crossover design, participants completed three trials: (1) no music (NM), (2) non-preferred (NP), and (3) preferred (PV) music. Participants completed three maximal IMTP tests on a force-plate-equipped IMTP apparatus with an immovable bar. Attempts lasted 5 s and were separated by 3 min of rest. Furthermore, participants completed three single maximal CMJ attempts separated by 3 min of rest on force plates. All attempts were averaged for analysis. At the commencement of IMTP and CMJ testing, participants were asked to rate how motivated and psyched up they felt during the exercise portion using a visual analog scale. For isometric performance, listening to PM resulted in increased peak force (p = 0.039; d = 0.41) and rate of force development at 200 ms (p = 0.023; d = 0.91) compared with NP. For CMJ, there were no differences between conditions for jump height (p = 0.912; η2 = 0.007) or peak power during the propulsive phase (p = 0.460; η2 = 0.003). Levels of motivation were significantly higher with PM compared with NM (p < 0.001; d = 2.3) and NP (p = 0.001; d = 2.0). Feelings of being psyched up were significantly higher with PM compared with NM (p < 0.001; d = 4.2) and NP (p = 0.001; d = 2.8). Findings suggest that preferred music enhances isometric strength and increases motivation and feelings of being psyched up. Thus, PM may be used as an ergogenic aid during short-duration maximal-effort activities.