You are looking at 161 - 170 of 4,573 items for :

  • Sport and Exercise Science/Kinesiology x
  • Physical Education and Coaching x
Clear All
Restricted access

Richard Ebreo, Louis Passfield and James Hopker

Purpose: To evaluate the reliability of calculating gross efficiency (GE) conventionally and using a back extrapolation (BE) method during high-intensity exercise (HIE). Methods: A total of 12 trained participants completed 2 HIE bouts (P1 = 4 min at 80% maximal aerobic power [MAP]; P2 = 4 min at 100%MAP). GE was calculated conventionally in the last 3 minutes of submaximal (50%MAP) cycling bouts performed before and after HIE (Pre50%MAP and Post50%MAP). To calculate GE using BE (BGE), a linear regression of GE submaximal values post-HIE were back extrapolated to the end of the HIE bout. Results: BGE was significantly correlated with Post50%MAP GE in P1 (r = .63; P = .01) and in P2 (r = .85; P = .002). Reliability data for P1 and P2 BGE demonstrate a mean coefficient of variation of 7.8% and 9.8% with limits of agreement of 4.3% and 4.5% in relative GE units, respectively. P2 BGE was significantly lower than P2 Post50%MAP GE (18.1% [1.6%] vs 20.3% [1.7%]; P = .01). Using a declining GE from the BE method, there was a 44% greater anaerobic contribution compared with assuming a constant GE during 4-minute HIE at 100%MAP. Conclusion: HIE acutely reduced BGE at 100%MAP. A greater anaerobic contribution to exercise as well as excess postexercise oxygen consumption at 100%MAP may contribute to this decline in efficiency. The BE method may be a reliable and valid tool in both estimating GE during HIE and calculating aerobic and anaerobic contributions.

Restricted access

Andrea Nicolò, Marco Montini, Michele Girardi, Francesco Felici, Ilenia Bazzucchi and Massimo Sacchetti

Purpose: Variables currently used in soccer training monitoring fail to represent the physiological demand of the player during movements like accelerations, decelerations, and directional changes performed at high intensity. We tested the hypothesis that respiratory frequency (f R) is a marker of physical effort during soccer-related high-intensity exercise. Methods: A total of 12 male soccer players performed a preliminary intermittent incremental test and 2 shuttle-run high-intensity interval training (HIIT) protocols, in separate visits. The 2 HIIT protocols consisted of 12 repetitions over 9 minutes and differed in the work-to-recovery ratio (15:30 vs 30:15 s). Work rate was self-paced by participants to achieve the longest possible total distance in each HIIT protocol. Results: Work-phase average metabolic power was higher (P < .001) in the 15:30-second protocol (31.7 [3.0] W·kg−1) compared with the 30:15-second protocol (22.8 [2.0] W·kg−1). Unlike heart rate and oxygen uptake, f R showed a fast response to the work–recovery alternation during both HIIT protocols, resembling changes in metabolic power even at supramaximal intensities. Large correlations (P < .001) were observed between f R and rating of perceived exertion during both 15:30-second (r = .87) and 30:15-second protocols (r = .85). Conclusions: Our findings suggest that f R is a good marker of physical effort during shuttle-run HIIT in soccer players. These findings have implications for monitoring training in soccer and other team sports.

Restricted access

Megan Chawansky

Restricted access

Nima Dehghansai and Joseph Baker

Initiatives have been designed to attract novice athletes and to enable transfer for experienced athletes. However, the authors have very little knowledge of the effectiveness of these programs. To further improve our understanding, this study explored the demographic and sporting careers of 225 participants attending one of the 10 Paralympian Search events held between 2016 and 2018. The sample consisted of participants with a wide range of impairments and sport experiential backgrounds. The majority of the participants reported having some experience in sports, suggesting that either the promotions reached athletes involved in sports already or the advertising appealed especially to this cohort. Athletes with impairments acquired at various stages of their lives (congenital, before adolescence, adolescence, early adulthood, and adulthood) displayed differences in their sporting trajectories, suggesting considerations for current developmental models. Furthermore, it should be considered to vary the testing locations of future events to increase the reach to rural areas and implement new methods to attract novice participants.

Open access

Alan J. McCubbin, Bethanie A. Allanson, Joanne N. Caldwell Odgers, Michelle M. Cort, Ricardo J.S. Costa, Gregory R. Cox, Siobhan T. Crawshay, Ben Desbrow, Eliza G. Freney, Stephanie K. Gaskell, David Hughes, Chris Irwin, Ollie Jay, Benita J. Lalor, Megan L.R. Ross, Gregory Shaw, Julien D. Périard and Louise M. Burke

It is the position of Sports Dietitians Australia (SDA) that exercise in hot and/or humid environments, or with significant clothing and/or equipment that prevents body heat loss (i.e., exertional heat stress), provides significant challenges to an athlete’s nutritional status, health, and performance. Exertional heat stress, especially when prolonged, can perturb thermoregulatory, cardiovascular, and gastrointestinal systems. Heat acclimation or acclimatization provides beneficial adaptations and should be undertaken where possible. Athletes should aim to begin exercise euhydrated. Furthermore, preexercise hyperhydration may be desirable in some scenarios and can be achieved through acute sodium or glycerol loading protocols. The assessment of fluid balance during exercise, together with gastrointestinal tolerance to fluid intake, and the appropriateness of thirst responses provide valuable information to inform fluid replacement strategies that should be integrated with event fuel requirements. Such strategies should also consider fluid availability and opportunities to drink, to prevent significant under- or overconsumption during exercise. Postexercise beverage choices can be influenced by the required timeframe for return to euhydration and co-ingestion of meals and snacks. Ingested beverage temperature can influence core temperature, with cold/icy beverages of potential use before and during exertional heat stress, while use of menthol can alter thermal sensation. Practical challenges in supporting athletes in teams and traveling for competition require careful planning. Finally, specific athletic population groups have unique nutritional needs in the context of exertional heat stress (i.e., youth, endurance/ultra-endurance athletes, and para-sport athletes), and specific adjustments to nutrition strategies should be made for these population groups.

Restricted access

Ryo Yamanaka, Hayato Ohnuma, Ryosuke Ando, Fumiya Tanji, Toshiyuki Ohya, Masahiro Hagiwara and Yasuhiro Suzuki

Purpose: Increases in maximal oxygen uptake (V˙O2max) and running economy improve performance in long-distance runners. Nevertheless, long-distance runners require sprinting ability to win, especially in the final phase of competitions. The authors determined the relationships between performance and sprinting ability, as well as other abilities in elite long-distance runners. Methods: The subjects were 12 elite long-distance runners. Mean official seasonal best times in 5000-m (5000 m-SB) and 10,000-m (10,000 m-SB) races within 1 year before or after the examination were 13:58.5 (0:18.7) and 28:37.9 (0:25.2) (mean [SD]), respectively. The authors measured 100-m and 400-m sprint times as the index of sprinting ability. They also measured V˙O2max and running economy (V˙O2 at 300 m·min−1 of running velocity). They used a single correlation analysis to assess relationships between 5000 m-SB or 10,000 m-SB and other elements. Results: There were significant correlations between 5000 m-SB was significantly correlated with 100-m sprint time (13.3 [0.7] s; r = .68, P = .014), 400-m sprint time (56.6 [2.7] s; r = .69, P = .013), and running economy (55.5 [3.9] mL·kg−1·min−1; r = .59, P = .045). There were significant correlations between 10,000 m-SB and 100-m sprint time (r = .72, P = .009) and 400-m sprint time (r = .85, P < .001). However, there was no significant correlation between 5000 m-SB or 10,000 m-SB and V˙O2max (72.0 [3.8] mL·kg−1·min−1). Conclusions: The authors' data suggest that sprinting ability is an important indicator of performance in elite long-distance runners.

Restricted access

Erin Calaine Inglis, Danilo Iannetta, Daniel A. Keir and Juan M. Murias

Purpose: To evaluate whether the coherence in the oxygen uptake (V˙O2) associated with the respiratory compensation point (RCP), near-infrared spectroscopy-derived muscle deoxyhemoglobin ([HHb]) break point ([HHb]BP), and maximal lactate steady state (MLSS) would persist at the midpoint and endpoint of a 7-month training and racing season. Methods: Eight amateur male cyclists were tested in 3 separate phases over the course of a cycling season (PRE, MID, and POST). Testing at each phase included a ramp-incremental test to exhaustion to determine RCP and [HHb]BP. The PRE and POST phases also included constant power output rides to determine MLSS. Results: Compared with PRE, V˙O2 at both RCP and [HHb]BP was greater at MID (delta: RCP 0.23 [0.14] L·min−1, [HHb]BP 0.33 [0.17] L·min−1) and POST (delta: RCP 0.21 [0.12], [HHb]BP 0.30 [0.14] L·min−1) (P < .05). V˙O2 at MLSS also increased from PRE to POST (delta: 0.17 [12] L·min−1) (P < .05). V˙O2 was not different at RCP, [HHb]BP, and MLSS at PRE (3.74 [0.34], 3.64 [0.40], 3.78 [0.23] L·min−1) or POST (3.96 [0.25], 3.95 [0.32], 3.94 [0.18] L·min−1) respectively, and RCP (3.98 [0.33] L·min−1) and [HHb]BP (3.97 [0.34] L·min−1) were not different at MID (P > .05). PRE–MID and PRE–POST changes in V˙O2 associated with RCP, [HHb]BP, and MLSS were strongly correlated (range: r = .85–.90) and demonstrated low mean bias (range = −.09 to .12 L·min−1). Conclusions: At all measured time points, V˙O2 at RCP, [HHb]BP, and MLSS were not different. Irrespective of phase comparison, direction, or magnitude of V˙O2 changes, intraindividual changes between each index were strongly related, indicating that interindividual differences were reflected in the group mean response and that their interrelationships are beyond coincidental.

Restricted access

Danielle Peers, Timothy Konoval and Rebecca Marsh Naturkach

This Foucauldian discourse analysis engages DePauw’s theory of disability and visibility to examine the construction of para-athletes within the websites of Canada’s “fully integrated” athletics sport system. The authors found that para-athletes remain largely unimaginable within most athletics websites. When present, para-athletes are often only imagined as marginal participants, or marginalized through medical and charitable discourses. The authors offer examples of para-athletes being reimagined primarily as athletes, and some examples where (para-)athletics was reimagined by identifying and removing barriers to full participation. The authors close with some learning points that may enable sport practitioners to change how they discursively construct para-athletes and thus contribute to a less marginalizing and exclusionary sport system.

Restricted access

Kirsti Van Dornick and Nancy L.I. Spencer

The purpose of this study was to examine the classification experiences (perspectives and reflections) of paraswimmers. Classification provides a structure for parasport, with the goal of reducing the impact of impairment on the outcome of competition. Guided by interpretive description, nine paraswimmers ranging in swimming experience and sport class were interviewed. Reflective notes were also collected. Transcribed interviews were analyzed inductively, followed by a deductive analysis using Nordenfelt’s dignity framework. Three themes represent the findings: access, diversity, and (un)certainty. Despite several positive experiences, paraswimmers also discussed inconsistencies in the process leading them to question competition fairness and classification accuracy. These findings suggest that continued efforts to improve the classification system are required. In addition, paraswimmers and their allies (e.g., coaches) require more information about the classification process to better understand the outcomes and to effectively advocate for their needs.