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Peter Leo, James Spragg, Iñigo Mujika, Verena Menz, and Justin S. Lawley

Purpose: The aim of this study was to investigate changes in the power profile of U23 professional cyclists during a competitive season based on maximal mean power output (MMP) and derived critical power (CP) and work capacity above CP (W′) obtained during training and racing. Methods: A total of 13 highly trained U23 professional cyclists (age = 21.1 [1.2] y, maximum oxygen consumption = 73.8 [1.9] mL·kg–1·min–1) participated in this study. The cycling season was split into pre-season and in-season. In-season was divided into early-, mid-, and late-season periods. During pre-season, a CP test was completed to derive CPtest and W′test. In addition, 2-, 5-, and 12-minute MMP during in-season were used to derive CPfield and W′field. Results: There were no significant differences in absolute 2-, 5-, and 12-minute MMP, CPfield, and W′field between in-season periods. Due to changes in body mass, relative 12-minute MMP was higher in late-season compared with early-season (P = .025), whereas relative CPfield was higher in mid- and late-season (P = .031 and P = .038, respectively) compared with early-season. There was a strong correlation (r = .77–.83) between CPtest and CPfield in early- and mid-season but not late-season. Bland–Altman plots and standard error of estimates showed good agreement between CPtest and in-season CPfield but not between W′test and W′field. Conclusion: These findings reveal that the power profile remains unchanged throughout the in-season, except for relative 12-minute MMP and CPfield in late-season. One pre-season and one in-season CP test are recommended to evaluate in-season CPfield and W′field.

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Patrick C. Maughan, Niall G. MacFarlane, and Paul A. Swinton

Purpose: To quantify and describe relationships between subjective and external measures of training load in professional youth soccer players. Methods: Data from differential ratings of perceived exertion (dRPE) and 7 measures of external training load were collected from 20 professional youth soccer players over a 46-week season. Relationships were described by repeated-measures correlation, principal component analysis, and factor analysis with oblimin rotation. Results: Significant positive (.44 ≤ r ≤ .99; P < .001) within-individual correlations were obtained across dRPE and all external training load measures. Correlation magnitudes were found to decrease when training load variables were expressed per minute. Principal component analysis provided 2 components, which described 83.3% of variance. The first component, which described 72.9% of variance, was heavily loaded by all measures of training load, while the second component, which described 10.4% of the variance, appeared to have a split between objective and subjective measures of volume and intensity. Exploratory factor analysis identified 4 theoretical factors, with correlations between factors ranging from .5 to .8. These factors could be theoretically described as objective volume, subjective volume, objective running, and objective high-intensity measures. Removing dRPE measures from the analysis altered the structure of the model, providing a 3-factor solution. Conclusions: The dRPE measures are significantly correlated with a range of external training load measures and with each other. More in-depth analysis showed that dRPE measures were highly related to each other, suggesting that, in this population, they would provide practitioners with similar information. Further analysis provided characteristic groupings of variables.

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Thimo Wiewelhove, Constantin Thase, Marcel Glahn, Anthony Hessel, Christoph Schneider, Laura Hottenrott, Tim Meyer, Michael Kellmann, Mark Pfeiffer, and Alexander Ferrauti

Purpose: To identify whether the use of active recovery (ACT) the day after high-intensity interval training (HIIT) benefits recovery and to assess whether individual responses to ACT are repeatable. Methods: Eleven well-trained, male intermittent-sport athletes (age: 25.5 ± 1.8 y) completed 4 HIIT sessions, each separated by a 2-week washout period. Of the 4 sessions, 2 were followed by passive recovery (PAS) and 2 by 60 minutes of moderate biking (ACT) 24 hours postexercise in the following sequences: ACT→PAS→ACT→PAS or PAS→ACT→PAS→ACT. Before and after HIIT and after 24 and 48 hours of recovery, maximal voluntary isometric strength (MVIC), countermovement jump height (CMJ), tensiomyographic markers of muscle fatigue (TMG), serum concentration of creatine kinase (CK), muscle soreness (MS), and perceived stress state (PS) were determined. Results: A 3-way repeated-measure analysis of variance with a triple-nested random effects model revealed a significant (P < .05) fatigue-related time effect of HIIT on markers of fatigue (MVIC↓; CMJ↓; TMG↑; CK↑; MS↑; PS↑). No significant (P > .05) main effect of recovery strategy was detected. In 9 subjects, the individual results revealed inconsistent and nonrepeatable responses to ACT, while a consistent and repeatable positive or negative response to ACT was found in 2 individuals. Conclusions: The repeated failure of ACT to limit the severity of fatigue was found both at the group level and with most individuals. However, a small percentage of athletes may be more likely to benefit repeatedly from either ACT or PAS. Therefore, the use of ACT should be individualized.

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Brandon J. Shad, Janice L. Thompson, James Mckendry, Andrew M. Holwerda, Yasir S. Elhassan, Leigh Breen, Luc J.C. van Loon, and Gareth A. Wallis

The impact of resistance exercise frequency on muscle protein synthesis rates remains unknown. The aim of this study was to compare daily myofibrillar protein synthesis rates over a 7-day period of low-frequency (LF) versus high-frequency (HF) resistance exercise training. Nine young men (21 ± 2 years) completed a 7-day period of habitual physical activity (BASAL). This was followed by a 7-day exercise period of volume-matched, LF (10 × 10 repetitions at 70% one-repetition maximum, once per week) or HF (2 × 10 repetitions at ∼70% one-repetition maximum, five times per week) resistance exercise training. The participants had one leg randomly allocated to LF and the other to HF. Skeletal muscle biopsies and daily saliva samples were collected to determine myofibrillar protein synthesis rates using 2H2O, with intracellular signaling determined using Western blotting. The myofibrillar protein synthesis rates did not differ between the LF (1.46 ± 0.26%/day) and HF (1.48 ± 0.33%/day) conditions over the 7-day exercise training period (p > .05). There were no significant differences between the LF and HF conditions over the first 2 days (1.45 ± 0.41%/day vs. 1.25 ± 0.46%/day) or last 5 days (1.47 ± 0.30%/day vs. 1.50 ± 0.41%/day) of the exercise training period (p > .05). Daily myofibrillar protein synthesis rates were not different from BASAL at any time point during LF or HF (p > .05). The phosphorylation status and total protein content of selected proteins implicated in skeletal muscle ribosomal biogenesis were not different between conditions (p > .05). Under the conditions of the present study, resistance exercise training frequency did not modulate daily myofibrillar protein synthesis rates in young men.

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Matías Henríquez, Aitor Iturricastillo, Arturo González-Olguín, Felipe Herrera, Sonny Riquelme, and Raul Reina

This study compared physical performance in a group of international cerebral palsy football players during two formats of small-sided games (SSGs) and performance in a simulated game (SG) according to players’ sport classes (FT1, FT2, and FT3). Internal load (heart rate and rating of perceived exertion) and external load (total distance, distance covered at different velocities, maximum speed reached, acceleration, and deceleration) were obtained with global positioning system devices during two formats of SSGs (2-a-side/SSG2 and 4-a-side/SSG4) and an SG (7-a-side). SSG2 demands faster actions compared with SSG4/SG, and significant differences and large effect sizes were found in the distance covered in Speed Zones 5 (16.0−17.9 km/hr) and 6 (>18.0 km/hr; p < .05; .35<ηp2<.50, large). Lower moderate accelerations and decelerations per minute in SSG4/SG compared with SSG2 were also found (p < .01; .77<ηp2<.81, large). In the SSG2 task, the FT3 players reached maximum speeds, covered more distance at the highest intensities, and performed more moderate/high accelerations/decelerations and more sprints compared with FT1 and FT2 players (p < .05; −0.85 < dg < −4.64, large). The SSG2 task could be the best option for discriminating physical demands in important variables for cerebral palsy football performance between classes FT3 versus FT1/FT2.

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Laura Prieto, Michael L. Norris, and Luis Columna

The purpose of this study was to examine the experiences of people with Parkinson’s (PwP) and their care partners (CPs) who participated in a Parkinson’s-focused community dance class in a northeastern state of the United States. In this qualitative inquiry, participants included five PwP and their respective CPs (n = 5). Three major, recurrent, and interrelated themes emerged from the data. These themes were (a) keep moving, (b) compassion in action, and (c) acceptance and freedom in dance. These themes captured personal and environmental factors that influenced the participation of PwP and their CPs in a dance class and how they perceived that dance influenced their quality of life. The themes described the obstacles, motives, and perceived outcomes of participating in dance. The findings emphasize the need for future dance interventions and programs that consider the CPs’ role in promoting participation for PwP in dance classes.

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Luca Cavaggioni, Athos Trecroci, Damiano Formenti, Luke Hogarth, Massimiliano Tosin, and Giampietro Alberti

The purpose of this study was to monitor the changes in breathing pattern, trunk muscle stabilization, and upper-body muscular power in Paralympic swimmers throughout a competitive season over three time points: October (T1), March (T2), and August (T3). Six top-level Paralympic swimmers voluntarily participated in this study. The Friedman test, the Bonferroni–Dunn multiple comparison post hoc analysis, and Kendall’s W concordance coefficient for the measure of effect were used. A significant difference was found in the breathing pattern, trunk stability, and upper-body power variables from the T1 to T3 season (p < .05). However, no significant changes were found in the T2 season. A long-term assessment of these fitness parameters may be of practical importance for better tailoring the training programs of top-level Paralympic swimmers.

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Yuri de Almeida Costa Campos, Jeferson M. Vianna, Miller P. Guimarães, Hiago L.R. Souza, Raúl Domínguez, Jefferson S. Novaes, Luis F.M. Leitão, Sandro F. Silva, and Victor M. Reis

Purpose: To identify the anaerobic threshold through the lactate threshold determined by Dmax and rating of perceived exertion (RPE) threshold by Dmax and to evaluate the agreement and correlation between lactate threshold determined by Dmax and RPE threshold by Dmax during an incremental test performed on the treadmill in long-distance runners. Methods: A total of 16 long-distance runners volunteered to participate in the study. Participants performed 2 treadmill incremental tests for the collection of blood lactate concentrations and RPE separated by a 48-hour interval. The incremental test started at 8 km·h−1, increasing by 1.2 km·h−1 every third minute until exhaustion. During each stage of the incremental test, there were pauses of 30 seconds for the collection of blood lactate concentration and RPE. Results: No significant difference was found between methods lactate threshold determined by Dmax and RPE threshold by Dmax methods (P = .664). In addition, a strong correlation (r = .91) and agreement through Bland–Altman plot analysis were found. Conclusions: The study demonstrated that it is possible to predict anaerobic threshold from the OMNI-walk/run scale curve through a single incremental test on the treadmill. However, further studies are needed to evaluate the reproducibility and objectivity of the OMNI-walk/run scale for anaerobic threshold determination.

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Lore Metz, Laurie Isacco, Kristine Beaulieu, S. Nicole Fearnbach, Bruno Pereira, David Thivel, and Martine Duclos

Background: While the popularity of aquatic physical activities continues to grow among women, the effects on energy expenditure (EE) and appetite control remain unknown. The objective of this study was to examine the effect of water temperature during aqua-cycling session on EE, rate of perceived exertion, energy intake, appetite sensations, and food reward in healthy premenopausal women. Methods: Participants completed three experimental sessions, in the postprandial condition, in a randomized order: a land control session (CON), an aqua-cycling session in 18 °C (EXO18), and an aqua-cycling session in 27 °C (EXO27). The EE, food intake, appetite sensations, and food reward were investigated for each condition. Results: EXO18 induced a significant increase in EE (p < .001) and oxygen consumption (p < .01) compared with EXO27. The carbohydrate oxidation was higher in EXO18 session compared with EXO27 and CON (p < .05 and p < .001, respectively). While fat oxidation was higher in exercise sessions compared with CONT (p < .01), no difference was observed between EXO18 and EXO27. Exercise sessions did not alter absolute energy intake session but induced a decrease in relative energy intake (p < .001) and in hunger, desire to eat, and prospective food consumption compared with CON (p < .001). The authors also show here that cold-water exposure can increase EE while rate of perceived exertion is lower at the end of exercise session compared with same exercise at 27 °C (p < .05).Conclusion: An exposure to a moderately cold-water during aqua-cycling is an efficient strategy to promote increased EE and decreased hunger, which may be effective for energy balance management in healthy premenopausal women.