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Sebastien Racinais, Julien D. Périard, Julien Piscione, Pitre C. Bourdon, Scott Cocking, Mohammed Ihsan, Mathieu Lacome, David Nichols, Nathan Townsend, Gavin Travers, Mathew G. Wilson, and Olivier Girard

Purpose: To investigate whether including heat and altitude exposures during an elite team-sport training camp induces similar or greater performance benefits. Methods: The study assessed 56 elite male rugby players for maximal oxygen uptake, repeated-sprint cycling, and Yo-Yo intermittent recovery level 2 (Yo-Yo) before and after a 2-week training camp, which included 5 endurance and 5 repeated-sprint cycling sessions in addition to daily rugby training. Players were separated into 4 groups: (1) control (all sessions in temperate conditions at sea level), (2) heat training (endurance sessions in the heat), (3) altitude (repeated-sprint sessions and sleeping in hypoxia), and (4) combined heat and altitude (endurance in the heat, repeated sprints, and sleeping in hypoxia). Results: Training increased maximal oxygen uptake (4% [10%], P = .017), maximal aerobic power (9% [8%], P < .001), and repeated-sprint peak (5% [10%], P = .004) and average power (12% [14%], P < .001) independent of training conditions. Yo-Yo distance increased (16% [17%], P < .001) but not in the altitude group (P = .562). Training in heat lowered core temperature and increased sweat rate during a heat-response test (P < .05). Conclusion: A 2-week intensified training camp improved maximal oxygen uptake, repeated-sprint ability, and aerobic performance in elite rugby players. Adding heat and/or altitude did not further enhance physical performance, and altitude appears to have been detrimental to improving Yo-Yo.

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Patricia Rehder-Santos, Raphael M. Abreu, Étore De F. Signini, Claudio D. da Silva, Camila A. Sakaguchi, Carla C. Dato, and Aparecida M. Catai

Background and Objective: Inspiratory muscle training (IMT) produced outstanding results in the physical performance of active subjects; however, little is known about the best training intensity for this population. The objective was to investigate the impact of an IMT of high intensity, using the critical inspiratory pressure (CIP), on inspiratory muscle strength (IMS), inspiratory muscle endurance (IME), peak power, and oxygen uptake of recreational cyclists; and to compare these results with moderate-intensity IMT (60% of maximal inspiratory pressure [MIP]). Methods: Thirty apparently healthy male recreational cyclists, 20–40 years old, underwent 11 weeks of IMT (3 times per week; 55 min per session). Participants were randomized into 3 groups: sham group (6 cmH2O; n = 8); 60% MIP (MIP60; n = 10) and CIP (n = 12). All participants performed the IMS test and incremental IME test at the first, fifth, ninth, and 13th weeks of the experimental protocol. Cardiopulmonary exercise testing was performed on an electromagnetic braking cycle ergometer pre-IMT and post-IMT. Data were analyzed using a 2-way repeated measures ANOVA (group and period factors). Results: IMS increased in CIP and MIP60 groups at the ninth and 13th weeks compared with the sham group (P < .001; β = 0.99). Regarding IME, there was an interaction between the CIP and MIP60 groups in all periods, except in the initial evaluation (P < .001; β = 1.00). Peak power (in watts) increased after IMT in CIP and MIP60 groups (P = .01; β = 0.67). Absolute oxygen uptake did not increase after IMT (P = .49; β = 0.05). Relative oxygen uptake to lean mass values did not change significantly (P = .48; β = 0.05). Conclusion: High-intensity IMT is beneficial on IMS, IME, and peak power, but does not provide additional gain to moderate intensity in recreational cyclists.

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Antonio Henrique Germano-Soares, Rafael M. Tassitano, Breno Quintela Farah, Aluísio Andrade-Lima, Marília de Almeida Correia, Aleš Gába, Nikola Štefelová, Pedro Puech-Leao, Nelson Wolosker, Gabriel Grizzo Cucato, and Raphael Mendes Ritti-Dias

Background: To examine the associations between physical activity (PA) and sedentary behavior (SB) with walking capacity and the effects of reallocating time from SB to PA in patients with symptomatic peripheral artery disease (PAD) using compositional data analysis. Methods: This cross-sectional study included 178 patients (34% females, mean age = 66 [9] y, body mass index = 27.8 [5.0] kg/m2, and ankle-brachial index = 0.60 [0.18]). Walking capacity was assessed as the total walking distance (TWD) achieved in a 6-minute walk test, while SB, light-intensity PA, and moderate to vigorous-intensity PA (MVPA) were measured by a triaxial accelerometer and conceptualized as a time-use composition. Associations between time reallocation among wake-time behaviors and TWD were determined using compositional isotemporal substitution models. Results: A positive association of MVPA with TWD (relative to remaining behaviors) was found in men (β ilr = 66.9, SE = 21.4, P = .003) and women (β ilr = 56.5, SE = 19.8; P = .005). Reallocating 30 minutes per week from SB to MVPA was associated with higher TWD in men (6.7 m; 95% confidence interval, 2.6–10.9 m) and women (4.5 m; 95% confidence interval, 1.5–7.5 m). Conclusions: The findings highlight, using a compositional approach, the beneficial and independent association of MVPA with walking capacity in patients with symptomatic PAD, whereas SB and light-intensity PA were not associated.

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Michael J. Shoemaker, Michaela Mattern, Hannah Scholten, Jessica Zeitler, and Shweta Gore

Background: The measurement of daily physical activity (DPA) is important for the prognosis and quantifying clinical outcomes in individuals with heart disease. The measurement of DPA is more feasible using subjective measures when compared with objective measures. The purpose of this systematic review of the literature was to identify the subjective measures of DPA that have established reliability and validity in individuals with heart disease to assist clinician and researcher instrument selection. Methods: A systematic search of PubMed, CINAHL, MEDLINE, and ProQuest databases was performed. Methodological rigor was assessed using 3 different quality appraisal tools. Qualitative synthesis of included studies was performed. Results: Twenty-two unique studies covering 19 subjective DPA measures were ultimately included. Methodological rigor was generally fair, and validity coefficients were moderate at best. Conclusions: Only 4 subjective measures that have established test–retest reliability and that provide an estimate of energy expenditure, metabolic equivalents, or minutes of DPA were compared against accelerometry or a DPA diary in patients with heart disease: SWISS Physical Activity Questionnaire, Total Activity Measure 1 and 2, and Mobile Physical Activity Logger. Depending on the clinician or researcher needs, instrument selection would depend on the recall period and the DPA construct being measured.

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Adrien Vachon, Nicolas Berryman, Iñigo Mujika, Jean-Baptiste Paquet, and Laurent Bosquet

Purpose: To assess the effects of a short-term taper on the ability to perform repeated high-intensity efforts, depending on players’ fatigue level following an intensive training block. Method: After a 3-day off-season camp, 13 players followed the same 3-week preseason training block followed by a 7-day exponential taper. Performance was assessed by a repeated high-intensity effort test before and after the taper. Total sprint time, percentage of decrement, and the number of sprints equal to or higher than 90% of the best sprint were retained for analysis. Players were a posteriori classified in normal training or acute fatigue groups based on their readiness to perform prior to the taper, assessed through the magnitude of difference in psychological (Profile of Mood State Questionnaire), cardiovascular (submaximal constant-duration cycling), and neuromuscular (countermovement jump) tests between the preintensive and postintensive training blocks. Results: Training load declined by 55% (9%) during the taper (P = .001, g = −2.54). The overall group showed a small improvement in total sprint time (−3.40% [3.90%], P = .04, g = −0.39) following the taper. Relative changes tended to be higher in the acute fatigue compared with the normal training group (−5.07% [4.52%] vs −1.45% [1.88%], respectively; P = .08; d = 1.01). No taper-induced improvement was observed in percentage of decrement or number of sprints equal to or higher than 90% of the best sprint. Conclusion: A 7-day taper consisting of 55% training load reduction improved repeated high-intensity effort performance in young elite rugby union players. Pretaper level of fatigue seems to be a key determinant in the taper supercompensation process, as acutely fatigued players at the end of the intensive training block tended to benefit more from the taper.

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Maria Jose Arias-Tellez, Francisco M. Acosta, Jairo H. Migueles, Jose M. Pascual-Gamarra, Elisa Merchan-Ramirez, Clarice M. de Lucena Martins, Jose M. Llamas-Elvira, Borja Martinez-Tellez, and Jonatan R. Ruiz

The role of lifestyle behaviors on neck adipose tissue (NAT), a fat depot that appears to be involved in the pathogenesis of different cardiometabolic diseases and in inflammatory status, is unknown. In this cross-sectional and exploratory study, the authors examined the relationship between sedentary time and physical activity (PA) with neck adiposity in young adults. A total of 134 subjects (69% women, 23 ± 2 years) were enrolled. The time spent in sedentary behavior and PA of different intensity were objectively measured for 7 consecutive days (24 hr/day), using a wrist (nondominant)-worn accelerometer. The NAT volume was assessed using computed tomography, and the compartmental (subcutaneous, intermuscular, and perivertebral) and total NAT volumes were determined at the level of vertebra C5. Anthropometric indicators and body composition (by dual-energy X-ray absorptiometry) were determined. The time spent in light physical activity and moderate physical activity (MPA) and the overall PA were inversely associated with the intermuscular NAT volume in men, as were the MPA and overall PA with total NAT volume (all ps ≤ .04). Sedentary time was directly related to the total NAT volume (p = .04). An opposite trend was observed in women, finding a direct relationship of MPA with the subcutaneous NAT; of light physical activity, MPA, and overall PA with the perivertebral NAT; and of light physical activity with total NAT volumes (all ps ≤ .05). The observed associations were weak, and after adjusting for multiplicity, the results became nonsignificant (p > .05). These findings suggest that the specific characteristics of PA (time and intensity) might have sex-dependent implications in the accumulation of NAT.

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Jonne A. Kapteijns, Kevin Caen, Maarten Lievens, Jan G. Bourgois, and Jan Boone

Purpose: To determine if there is a link between the demands of competitive game activity and performance profiles of elite female field hockey players. Methods: Global positioning systems (GPS) were used to quantify running performance of elite female field hockey players (N = 20) during 26 competitive games. Performance profiles were assessed at 2 time points (preseason and midseason) for 2 competitive seasons. A battery of anthropometric and performance field-based tests (30–15 intermittent fitness test, incremental run test, 10–30-m speed test, T test, and vertical jump test) were used to determine the performance profiles of the players. Results: Players covered a mean total distance of 5384 (835) m, of which 19% was spent at high intensities (zone 5: 796 [221] m; zone 6: 274 [105] m). Forwards covered the lowest mean total distance (estimated marginal means 4586 m; 95% confidence interval, 4275–4897), whereas work rate was higher in forwards compared with midfielders (P = .006, d = 0.43) and central defenders (P = .001, d = 1.41). Players showed an improvement in body composition and anaerobic performance from preseason to midseason. Aerobic performance capacity (maximal oxygen uptake and speed at the 4-mM lactate threshold) was positively correlated with high-intensity activities. Conclusions: There is a clear relationship between running performance and aerobic performance profiles in elite female hockey players. These results highlight the importance of a well-developed aerobic performance capacity in order to maintain a high performance level during hockey games.

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Alejandro Pérez-Castilla, Daniel Boullosa, and Amador García-Ramos

Objective: To evaluate the sensitivity of the iLOAD® application to detect the changes in mean barbell velocity of complete sets following power- and strength-oriented resistance training (RT) programs. Methods: Twenty men were randomly assigned to a power training group (countermovement jump and bench press throw at 40% of the 1-repetition maximum [1RM]) or strength training group (back squat and bench press at 70% to 90% of 1RM). Single sets of 10 repetitions at 25% and 70% of 1RM during the back squat and bench press exercises were assessed before and after the 4-week RT programs simultaneously with the iLOAD® application and a linear velocity transducer. Results: The power training group showed a greater increment in velocity performance at the 25% of 1RM (effect size range = 0.66–1.53) and the 70% of 1RM (effect size range = 0.11–0.30). The percent change in mean velocity after the RT programs highly correlated between the iLOAD® application and the linear velocity transducer for the back squat (r range = .85–.88) and bench press (r range = .87–.93). However, the iLOAD® application revealed a 2% greater increase in mean velocity after training compared to the linear velocity transducer. Conclusions: The iLOAD® application is a cost-effective, portable, and easy-to-use tool which can be used to detect changes in mean barbell velocity after power- and strength-oriented RT programs.

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Coral L. Hanson, Paul Kelly, Lis Neubeck, Jordan Bell, Holly Gibb, and Kai Jin

Background: Physical activity (PA) levels vary across specific population groups, contributing to health inequalities. Little is known about how local authority leisure centers contribute to population PA and whether this differs by age, sex, or socioeconomic group. Methods: The authors calculated weekly leisure center–based moderate/vigorous PA for 20,904 registered adult users of local authority leisure facilities in Northumberland, United Kingdom, between July 2018 and June 2019, using administrative data. The authors categorized activity levels (<30, 30–149, and ≥150 min/wk) and used ordinal regression to examine predictors for activity category achieved. Results: Registered users were mainly female (58.7%), younger (23.9% of users aged 18–29 y vs 10.1% of those aged 70+ y), and from the 2 most affluent socioeconomic quintiles (53.7%). Median weekly moderate/vigorous leisure center–based activity was 55 minutes per week (interquartile range: 30–99). Being female (odds ratio: 2.09; 95% confidence interval, 1.95–2.35), older (odds ratio: 1.14; 95% confidence interval, 1.11–1.16), and using a large facility (odds ratio: 1.21; 95% confidence interval, 1.03–1.42) were positive predictors of leisure center–based PA. Conclusion: Older adults and females were more likely to be active and achieve the recommended PA levels through usage of the centers. Widespread use of this novel measure of leisure center–based activity would improve the understanding of how local authority leisure centers can address physical inactivity and its associated inequalities.

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Danae Dinkel, Kelsey Lu, Jemima John, Kailey Snyder, and Lisette T. Jacobson

Background: Physical activity (PA), sedentary behavior, and sleep are interconnected, promoting optimal health. Few studies have examined these factors holistically. Therefore, the purpose of this study was to capture the 24-hour activity cycles of the US population by examining PA, sedentary behavior, and sleep based on the presence of a child within the home, as well as gender and weight. Methods: Cross-sectional health-related variables from the National Health and Nutrition Examination Survey were used for analysis. The primary variables were the total and type of PA (recreation, work, and active transportation), sedentary behavior, and sleep. Chi-square and regression models were applied to compare the outcomes across participants’ characteristics. Results: The adults with children within the home reported less recreational PA, more work activity, less sedentary activity, and less sleep, but no differences in total PA. The females with children in the home not only had the lowest levels of recreational activity and sleep, but also the lowest levels of sedentary behavior. The obese individuals with children in the home had less sedentary time than the adults without children in the home, regardless of weight status. Conclusions: Unhealthy sleep and PA behaviors are prevalent in adults with children living at home, and women are particularly impacted.