Background: Increasing nitric oxide bioavailability may induce physiological effects that enhance endurance exercise performance. This review sought to evaluate the performance effects of consuming foods containing compounds that may promote nitric oxide bioavailability.Methods: Scopus, Web of Science, Ovid Medline, EMBASE and SportDiscus were searched, with included studies assessing endurance performance following consumption of foods containing nitrate, L-arginine, L-citrulline or polyphenols. Random effects meta-analysis was conducted, with subgroup analyses performed based on food sources, sex, fitness, performance test type and supplementation protocol (e.g. duration).Results: One hundred and eighteen studies were included in the meta-analysis, which encompassed 59 polyphenol studies, 56 nitrate studies and three L-citrulline studies. No effect on exercise performance following consumption of foods rich in L-citrulline was identified (SMD=-0.03, p=0.24). Trivial but significant benefits were demonstrated for consumption of nitrate and polyphenol-rich foods (SMD=0.15 and 0.17, respectively,p<0.001), including performance in time-trial, time-to-exhaustion and intermittent-type tests, and following both acute and multiple-day supplementation, but no effect of nitrate or polyphenol consumption was found in females. Among nitrate-rich foods, beneficial effects were seen for beetroot, but not red spinach or Swiss chard and rhubarb. For polyphenol-rich foods, benefits were found for grape, (nitrate-depleted) beetroot, French maritime pine, Montmorency cherry and pomegranate, while no significant effects were evident for New Zealand blackcurrant, cocoa, ginseng, green tea or raisins. Considerable heterogeneity between polyphenol studies may reflect food-specific effects or differences in study designs and subject characteristics. Well-trained males (V̇O_2max≥65 ml.kg.min^-1) exhibited small, significant benefits following polyphenol, but not nitrate consumption.Conclusion: Foods rich in polyphenols and nitrate provide trivial benefits for endurance exercise performance, although these effects may be food dependent. Highly trained endurance athletes do not appear to benefit from consuming nitrate-rich foods but may benefit from polyphenol consumption. Further research into food sources, dosage and supplementation duration to optimise the ergogenic response to polyphenol consumption is warranted. Further studies should evaluate whether differential sex-based responses to nitrate and polyphenol consumption are attributable to physiological differences or sample size limitations.Other: The review protocol was registered on the Open Science Framework (https://osf.io/u7nsj) and no funding was provided.

The effect of the menstrual cycle on athlete performance, wellbeing and perceived exertion and fatigue is not well understood. Furthermore, it has not been investigated specifically in Australian Football athletes. This pilot study aimed to explore how naturally menstruating Australian Football athletes may be affected by menstrual cycle phase. The data collected from the routine monitoring of five naturally menstruating athletes (average menstrual cycle length of 28 ± 3 [SD] days) in one team (athlete age range 18–35 years) competing in the Women’s Australian Football League during the 2019 season were retrospectively analysed to compare performance (countermovement jump parameters and adductor squeeze pressure), perceived exertion, perceived fatigue and wellbeing (perceived sleep quality, stress and soreness) outcomes between the follicular and luteal phases. Performance, perceived exertion, stress and soreness did not appear to be affected by menstrual cycle phase (p > 0.17). However, perceived fatigue appeared to be significantly greater (p = 0.042) and sleep quality worse (p = 0.005) in the luteal phase. This pilot study suggests further research focusing on the effect of menstrual cycle phase on subjective fatigue and wellbeing is warranted.

There are no known objective biomarkers to assist with the diagnosis of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). A small number of studies have shown that ME/CFS patients exhibit an earlier onset of ventilatory threshold (VT) on the second of two cardiopulmonary exercise tests (CPET) performed on consecutive days. However, cut-off values which could be used to differentiate between ME/CFS patients have not been established. 16 ME/CFS patients and 10 healthy controls underwent CPET on a cycle-ergometer on 2-consecutive days. Heart rate (HR), ventilation, ratings of perceived exertion (RPE) and work rate (WR) were assessed on both days. WR at VT decreased from day 1 to day 2 and by a greater magnitude in ME/CFS patients (p < 0.01 group × time interaction). No interaction effects were found for any other parameters. ROC curve analysis of the percentage change in WR at VT revealed decreases of − 6.3% to − 9.8% provided optimal sensitivity and specificity respectively for distinguishing between patients with ME/CFS and controls. The decrease in WR at VT of 6.3–9.8% on the 2nd day of consecutive-day CPET may represent an objective biomarker that can be used to assist with the diagnosis of ME/CFS.

We present new high-speed photometric observations of the rapidly oscillating Ap (roAp) star γ Equ acquired on 26 nights during 1992. A frequency analysis of these observations reveals the presence of four p modes with frequencies of 1339, 1366, 1397 and 1427 μHz. These frequencies are all roughly equally spaced by about 30 μHz, which we interpret as the spacing of alternating even and odd ℓ modes for a slightly evolved A-type star. This interpretation leads to an asteroseismological luminosity estimate for γ Equ of M_V(Δ) = 1.8, which is in good agreement with the parallax luminosity M_V(π) = 1.9.

To consolidate and evaluate meta-analyses reporting the effects of blood flow restricted exercise (BFRE) on measures of health and physical fitness across all populations. This preregistered umbrella review followed PRISMA guidelines. A comprehensive search of five databases identified meta-analyses evaluating the effects of BFRE interventions (aerobic, resistance, combined) compared to exercising and non-exercising control conditions on measures of health and performance. A multilevel meta-analysis of standardised mean differences (SMDs) was conducted to examine the effects of BFRE. Subgroup analyses were conducted for the participant and intervention characteristics. Risk of bias was assessed using the AMSTAR-2. 47 meta-analyses comprised of 265 unique studies were included. All reviews were rated as low-moderate quality. BFRE had a small effect on hypertrophy (SMD ​= ​0.39, p ​< ​0.001) and a moderate effect on strength (SMD ​= ​0.61, p ​< ​0.001) when compared to low load, but not high load resistance training (hypertrophy, SMD = −0.13, p ​= ​0.142; strength, SMD = -0.28, p ​< ​0.001). BFRE had small-to-moderate effects on aerobic fitness (SMD = 0.50, p ​< ​0.001), vascular health (SMD = 0.45, p ​< ​0.001), blood pressure (SMD = 0.46, p ​< ​0.001), and muscular power (SMD = 0.56, p ​< ​0.001). BFRE had no effect on physical function (SMD = 0.16, p ​= ​0.096), pain (SMD = 0.00, p ​= ​0.996), and speed (SMD = 0.22, p ​= ​0.213). BFRE is a viable option to improve hypertrophy, strength, aerobic fitness, and vascular health across various populations, though its effects on hypertrophy and strength are smaller when compared to traditional high load resistance training. It doesn't appear to offer any additional benefits than other training methods for physical function, pain, or speed, although sub-analyses suggest further research is warranted in select areas of application.

The maximal rate of heart rate (HR) increase (rHRI), a marker of HR acceleration during transition from rest to submaximal exercise, correlates with exercise performance. In this cohort study, whether rHRI tracked performance better when evaluated over shorter time-periods which include a greater proportion of HR acceleration and less steady-state HR was evaluated. rHRI and five-km treadmill running time-trial performance (5TTT) were assessed in 15 runners following one week of light training (LT), two weeks of heavy training (HT) and 10-day taper (T). rHRI was the first derivative maximum of a sigmoidal curve fit to one, two, three and four minutes of R-R data during transition from rest to running at 8 km/h (rHRI_8 km/h), 10.5 km/h_, 13 km/h and transition from 8 to 13 km/h (rHRI_8–13km/h). 5TTT time increased from LT to HT (effect size [ES] 1.0, p < 0.001) then decreased from HT to T (ES −1.7, p < 0.001). 5TTT time was inversely related to rHRI_8 km/h assessed over two (B = −5.54, p = 0.04) three (B = −5.34, p = 0.04) and four (B = −5.37, p = 0.04) minutes, and rHRI_8–13km/h over one (B = −11.62, p = 0.006) and three (B = −11.44, p = 0.03) minutes. 5TTT correlated most consistently with rHRI_8 km/h. rHRI_8 km/h assessed over two to four minutes may be suitable for evaluating athlete responses to training.