Purpose: To describe pacing strategy in a 24-h running race and its interaction with sex, age group, athletes' performance group and race edition. Methods: Data from 398 male and 103 female participants of 5 editions were obtained based on a minimum 19.2-h effective-running cut-off. Mean running speed from each hour was normalised to the 24-h mean speed for analyses. Results: Mean overall performance was 135.6 ± 33.0 km with a mean effectiverunning time of 22.4 ± 1.3 h. Overall data showed a reverse J-shaped pacing strategy, with a significant reduction in speed from the second last to the last hour. Two-way mixed ANOVAs showed significant interactions between racing time and both athletes' performance group (F = 7.01; P < 0.001; p 2 = 0.04) and race edition (F = 3.01; P < 0.001; p 2 = 0.02), but not between racing time and both sex (F = 1.57; P = 0.058; p 2 < 0.01) and age group (F = 1.25; P = 0.053; p 2 = 0.01). Pearson's product-moment correlations showed an inverse moderate association between performance and normalised mean running speed in the first 2 h (r = -0.58; P < 0.001) but not in the last 2 h (r = 0.03; P = 0.480). Conclusions:While the general behaviour represents a rough, reverse J-shaped pattern, fastest runners start at lower relative intensities and display a more even pacing strategy than slower runners. The 'herd behaviour' seems to interfere with pacing strategy across editions, but not sex or age group of runners.

Introduction: The success of training depends on the balance between training load magnitude and recovery. Objective: Verify the effect of training load distribution on recovery status, vigor and fatigue in volleyball players during a season. Methods: Nine male athletes from a professional volleyball team participated in the study. During 19 weeks of the season, quantification of the training load was performed through the session rating of perceived exertion (RPE) method, evaluation of the athletes' recovery status through the Total Quality Recovery (TQR) scale, and evaluation of the profile of mood state through the POMS questionnaire, with research focus for the subscales vigor and fatigue. Results: The average total weekly training load (TWTL) was 3206 ± 685.5 A. Us and the average recovery of the whole season was 15.3 ± 0.57. The mean values of fatigue and vigor were 11 ± 3.05 and 19.4 ± 2.84, respectively. Significant differences were found for the variables RPE, fatigue and Energy Index (Vigor - Fatigue) in the three different periods of the season (Preparatory Period, Competitive Period I and Competitive Period II). Conclusion: It was concluded that the training load and recovery monitoring methods used throughout the season were effective in controlling the variables, with a positive impact of training loads verified on the recovery values presented by the athletes. Level of Evidence III; Diagnostic study.

This study aimed to analyse the reproducibility of mean power output during 20-min cycling time-trials, in a remote home-based setting, using the virtual-reality cycling software, Zwift. Forty-four cyclists (11 women, 33 men; 37 ± 8 years old, 180 ± 8 cm, 80.1 ± 13.2 kg) performed 3 x 20-min time-trials on Zwift, using their own setup. Intra-class correlation coefficient (ICC), coefficient of variation (CV) and typical error (TE) were calculated for the overall sample, split into 4 performance groups based on mean relative power output (25% quartiles) and sex. Mean ICC, TE and CV of mean power output between time-trials were 0.97 [0.95—0.98], 9.36 W [8.02—11.28 W], and 3.7% [3.2—4.5], respectively. Women and men had similar outcomes (ICC: 0.96 [0.89—0.99] vs 0.96 [0.92—0.98]; TE: 8.30 W [6.25—13.10] vs. 9.72 W [8.20—12.23]; CV: 3.8% [2.9—6.1] vs. 3.7% [3.1—4.7], respectively), although cyclists from the first quartile showed a lower CV in comparison to the overall sample (Q1: 2.6% [1.9—4.1] vs. overall: 3.7% [3.2—4.5]). Our results indicate that power output during 20-minute cycling time-trials on Zwift are reproducible and provide sports scientists, coaches and athletes, benchmark values for future interventions in a virtual-reality environment.

The version in the Kent Academic Repository may differ from the final published version. Users are advised to check http://kar.kent.ac.uk for the status of the paper. Users should always cite the published version of record.

TO THE EDITOR: Podlogar et al. ( 1) have nicely discussed current methods for classifying athletes in applied physiology studies attending to their training or performance level. We agree with them that relying on a single physiological marker such as maximum oxygen uptake is not without limitations and endorse the use of more performance-based indicators. However, before proposing critical power/speed (CP/ CS) as the primary indicator of an athlete's training status, the robustness of these variables and the best method for their determination remains to be confirmed. Differences in mathematical models or test durations can indeed have a remarkable impact on an individual's CP/CS (e.g., up to $1 km/ h for CS in top-level runners) (2).More research is needed to provide reference or "normative" values of CP/CS allowing classification of athletes into different performance/fitness categories. An alternative, at least in cycling, might be classifying athletes attending to the highest power output that they can achieve for a given duration-the so-called "mean maximum power" (MMP) (3). This approach does not require the use of mathematical calculations or additional laboratory testing and is sensitive enough to allow discerning actual performance even between the two highest category levels-Union Cycliste Internationale [UCI] ProTeam versus UCI WorldTour-in professional cyclists (4). We have recently reported normative MMP values for male (n = 144) (4) and female professional cyclists (n = 44) (5). If a similar approach was used in cyclists of a lower training/competition level, scientists and coaches could accurately classify participants in cycling physiology studies.

Sodium bicarbonate (NaHCO3) is a widely researched ergogenic aid, but the optimal blinding strategy during randomised placebo-controlled trials is unknown. In this multi-study project, we aimed to determine the most efficacious ingestion strategy for blinding NaHCO3 research. During study one, 16 physically active adults tasted 0.3 g kg−1 body mass NaHCO3 or 0.03 g kg−1 body mass sodium chloride placebo treatments given in different flavour (orange, blackcurrant) and temperature (chilled, room temperature) solutions. They were required to guess which treatment they had received. During study two, 12 recreational athletes performed time-to-exhaustion (TTE) cycling trials (familiarisation, four experimental). Using a randomised, double-blind design, participants consumed 0.3 g kg−1 body mass NaHCO3 or a placebo in 5 mL kg−1 body mass chilled orange squash/water solutions or capsules and indicated what they believed they had received immediately after consumption, pre-TTE and post-TTE. In study one, NaHCO3 prepared in chilled orange squash resulted in the most unsure ratings (44%). In study two, giving NaHCO3 in capsules resulted in more unsure ratings than in solution after consumption (92 vs 33%), pre-TTE (67 vs. 17%) and post-TTE (50 vs. 17%). Administering NaHCO3 in capsules was the most efficacious blinding strategy which provides important implications for researchers conducting randomised placebo-controlled trials.

Background Research has shown that ingesting 0.3 g·kg−1 body mass sodium bicarbonate (NaHCO3) can improve time-to-exhaustion (TTE) cycling performance, but the influence of psychophysiological mechanisms on ergogenic effects is not yet understood. Objective This study retrospectively examined whether changes in TTE cycling performance are mediated by positive expectations of receiving NaHCO3 and/or the decline in blood bicarbonate during exercise. Methods In a randomised, crossover, counterbalanced, double-blind, placebo-controlled design, 12 recreationally trained cyclists (maximal oxygen consumption, 54.4 ± 5.7 mL·kg·min−1) performed four TTE cycling tests 90 min after consuming: (1) 0.3 g·kg−1 body mass NaHCO3 in 5 mL·kg−1 body mass solution, (2) 0.03 g·kg−1 body mass sodium chloride in solution (placebo), (3) 0.3 g·kg−1 body mass NaHCO3 in capsules and (4) cornflour in capsules (placebo). Prior to exercise, participants rated on 1–5 Likert type scales how much they expected the treatment they believe had been given would improve performance. Capillary blood samples were measured for acid-base balance at baseline, pre-exercise and post-exercise. Results Administering NaHCO3 in solution and capsules improved TTE compared with their respective placebos (solution: 27.0 ± 21.9 s, p = 0.001; capsules: 23.0 ± 28.1 s, p = 0.016). Compared to capsules, NaHCO3 administered via solution resulted in a higher expectancy about the benefits on TTE cycling performance (Median: 3.5 vs. 2.5, Z = 2.135, p = 0.033). Decline in blood bicarbonate during exercise was higher for NaHCO3 given in solution compared to capsules (2.7 ± 2.1 mmol·L−1, p = 0.001). Mediation analyses showed that improvements in TTE cycling were indirectly related to expectancy and decline in blood bicarbonate when NaHCO3 was administered in solution but not capsules. Conclusions Participants’ higher expectations when NaHCO3 is administered in solution could result in them exerting themselves harder during TTE cycling, which subsequently leads to a greater decline in blood bicarbonate and larger improvements in performance. Key Points Ingesting 0.3 g·kg−1 body mass sodium bicarbonate in solution and capsules improved time-to-exhaustion cycling performance Positive expectancy about the benefits of sodium bicarbonate and decline in blood bicarbonate were higher when sodium bicarbonate was administered in solution compared with capsules Improvements in time-to-exhaustion cycling performance for sodium bicarbonate administered in solution were related to expectancy and the enhanced extracellular buffering response

No abstract