Browse

You are looking at 1 - 10 of 5,636 items for :

  • Physical Education and Coaching x
  • Sport and Exercise Science/Kinesiology x
  • Refine by Access: All Content x
Clear All
Restricted access

Pedro L. Valenzuela, Almudena Montalvo-Perez, Lidia B. Alejo, Mario Castellanos, Jaime Gil-Cabrera, Eduardo Talavera, Alejandro Lucia, and David Barranco-Gil

Purpose : Some power meters are available in both bilateral and unilateral versions. However, despite the popularity of the latter, their validity remains unknown. We aimed to analyze the validity of a unilateral pedal power meter for estimating actual (“bilateral”) power output (PO). Methods: Thirty-three male cyclists were assessed at different POs (steady cycling at 100–500 W, as well as all-out sprints), pedaling cadences (70, 85, and 100 repetitions·min−1), and cycling positions (seated and standing). The PO estimated by a left-only power meter (Favero Assioma Uno) was compared with the actual PO computed by a bilateral power meter (Favero Assioma Duo), and the level of bilateral asymmetry (most- vs least-powerful leg) with the latter system was also computed. Results: Nonsignificant differences, high intraclass correlation coefficients (≥.90), and low coefficients of variation (consistently ≤5% except for low PO levels, ie, 5%–7% at 100 W) were found between Favero Assioma Uno and Favero Assioma Duo. However, although a strong intraclass correlation coefficient (.995) was found between both legs, asymmetry values of 4% to 6% were found for all conditions except when pedaling at the lowest PO (100 W), in which asymmetry increased up to 10% to 13%. Conclusions: Although cyclists tend to present some level of bilateral asymmetry during cycling (particularly at low PO), Favero Assioma Uno provides overall valid estimates of actual PO and is, therefore, an economical alternative to bilateral power meters. Caution is needed, however, when interpreting data at the individual level in cyclists with high levels of asymmetry.

Restricted access

Felipe Guimarães Teixeira, Paulo Tadeu Cardozo Ribeiro Rosa, Roger Gomes Tavares Mello, and Jurandir Nadal

Purpose: The study aimed to identify the variables that differentiate judo athletes at national and regional levels. Multivariable analysis was applied to biomechanical, anthropometric, and Special Judo Fitness Test (SJFT) data. Method: Forty-two male judo athletes from 2 competitive groups (14 national and 28 state levels) performed the following measurements and tests: (1) skinfold thickness, (2) circumference, (3) bone width, (4) longitudinal length, (5) stabilometric tests, (6) dynamometric tests, and (7) SJFT. The variables with significant differences in the Wilcoxon rank-sum test were used in stepwise logistic regression to select those that better separate the groups. The authors considered models with a maximum of 3 variables to avoid overfitting. They used 7-fold cross validation to calculate optimism-corrected measures of model performance. Results: The 3 variables that best differentiated the groups were the epicondylar humerus width, the total number of throws on the SJFT, and the stabilometric mean velocity of the center of pressure in the mediolateral direction. The area under the receiver-operating-characteristic curve for the model (based on 7-fold cross validation) was 0.95. Conclusion: This study suggests that a reduced set of anthropometric, biomechanical, and SJFT variables can differentiate judo athlete’s levels.

Open access

Alannah K.A. McKay, Trent Stellingwerff, Ella S. Smith, David T. Martin, Iñigo Mujika, Vicky L. Goosey-Tolfrey, Jeremy Sheppard, and Louise M. Burke

Throughout the sport-science and sports-medicine literature, the term “elite” subjects might be one of the most overused and ill-defined terms. Currently, there is no common perspective or terminology to characterize the caliber and training status of an individual or cohort. This paper presents a 6-tiered Participant Classification Framework whereby all individuals across a spectrum of exercise backgrounds and athletic abilities can be classified. The Participant Classification Framework uses training volume and performance metrics to classify a participant to one of the following: Tier 0: Sedentary; Tier 1: Recreationally Active; Tier 2: Trained/Developmental; Tier 3: Highly Trained/National Level; Tier 4: Elite/International Level; or Tier 5: World Class. We suggest the Participant Classification Framework can be used to classify participants both prospectively (as part of study participant recruitment) and retrospectively (during systematic reviews and/or meta-analyses). Discussion around how the Participant Classification Framework can be tailored toward different sports, athletes, and/or events has occurred, and sport-specific examples provided. Additional nuances such as depth of sport participation, nationality differences, and gender parity within a sport are all discussed. Finally, chronological age with reference to the junior and masters athlete, as well as the Paralympic athlete, and their inclusion within the Participant Classification Framework has also been considered. It is our intention that this framework be widely implemented to systematically classify participants in research featuring exercise, sport, performance, health, and/or fitness outcomes going forward, providing the much-needed uniformity to classification practices.

Restricted access

Fernando Pareja-Blanco, Lucas A. Pereira, Valter P. Reis, Victor Fernandes, Ademir F.S. Arruda, Aristide Guerriero, Pedro E. Alcaraz, Tomás T. Freitas, and Irineu Loturco

Purpose: To examine the changes in resisted sprint performance and kinematics provoked by different sled loads in elite sprinters and rugby players. Methods: Eight elite male sprinters and 10 rugby union players performed 20-m sprints under 3 loading conditions (0%, 20%, and 60% body mass [BM]). Sprint time was measured in 0 to 5, 5 to 10, and 10 to 20 m, while stride length and hip, knee, and ankle angles were measured using an 8-sensor motion analysis system at the same distances. Results: Sprinters were significantly faster than rugby players in unresisted and resisted sprints using 20% BM (effect size, “ES” [90% confidence limit, CL] range: 0.65 [0.03 to 1.27]; 3.95 [3.10 to 4.81]), but these differences were not significant at 60% BM. Compared to rugby players, sprinters showed lower velocity decrement in resisted sprints using 20% BM (ES [90% CL] range: 0.75 [0.06 to 1.44]; 2.43 [0.83 to 4.02], but higher velocity decrement using 60% BM (ES [90% CL] range: 1.13 [0.43 to 1.82]; 1.46 [0.81 to 2.11]). No significant differences were detected in stride length between sprinters and rugby players for any sprint condition (ES [90% CL] range: 0.02 [−0.72 to 0.76]; 0.84 [0.13 to 1.54]). Rugby players showed higher hip flexion in resisted sprints (ES [90% CL] range: 0.30 [−0.54 to 1.14]; 1.17 [0.20 to 2.15]) and lower plantar flexion in both unresisted and resisted sprints (ES [90% CL] range: 0.78 [0.18 to 1.38]; 1.69 [1.00 to 2.38] than sprinters. Conclusions: The alterations induced by resisted sprints in sprint velocity and running technique differed between sprinters and rugby players. Some caution should be taken with general sled loads prescriptions, especially when relative loads are based on distinct percentages of BM, as training responses vary among sports and individuals.

Restricted access

Jiajun Shi, Danxia Yu, Yaohua Yang, Hui Cai, Jie Wu, Qiuyin Cai, Jirong Long, Wei Zheng, Wanghong Xu, and Xiao-Ou Shu

Increasing evidence has suggested that physical activity may modulate gut microbiome composition. We investigated associations of long-term regular exercise with gut microbiota among middle-aged and older urban Chinese individuals. Gut microbiota was assessed using 16S ribosomal ribonucleic acid gene sequencing of stool samples from 2,151 participants from the Shanghai Women’s Health Study and Shanghai Men’s Health Study. Participants were free of cancer, diabetes, and cardiovascular diseases at the time of stool sample collection. Physical activity was assessed in repeat surveys between 1996 and 2015 using validated questionnaires. Regular exercise was defined as any type of leisure-time physical activity with a standard metabolic equivalent score >3.0. Stool samples were collected using the 95% ethanol method between 2015 and 2018 with an average of 3.0 years (SD = 0.9) after the latest exposure assessment. General linear regression and permutational multivariate analysis of variance were carried out to evaluate associations of microbial α- and β-diversity with regular exercise participation. Logistic regression and linear regression models were used to evaluate the prevalence and relative abundance of individual taxa in association with regular exercise. Regular exercise was significantly associated with β-diversity (Bray–Curtis and Jaccard dissimilarities, both false discovery rates = 0.03%, 0.12% and 0.09% variance explained, respectively) but not with α-diversity. Relative abundance of genus Ruminococcus was significantly lower among regular exercisers compared with nonexercisers (median relative abundance: 0.64% vs. 0.81%, false discovery rate <0.10). Further studies are needed to validate the findings from this study and evaluate health benefits of regular exercise on gut microbiota.

Restricted access

Cyril Besson, Kenny Guex, Laurent Schmitt, Boris Gojanovic, and Vincent Gremeaux

Purpose: To present training load (TL) and heart-rate variability (HRV) in an elite sprinter monitored before, during, and after a COVID-19 infection until successful return to performance. Methods: TL, subjective morning fatigue (MF), and supine HRV were monitored during a 12-week period. Results: During a high-TL period (training camp), MF and heart rate increased and vagally mediated HRV variables decreased. MF increased and stayed high 3 days after the camp despite decrease in TL. In contrast, 4 days after the camp, heart rate decreased and vagally mediated HRV variables increased, reflecting parasympathetic hyperactivity. Elevated MF and suboptimal training performance led to a PCR test decision, which returned positive. After a 10-day training suspension, TL was progressively increased with low MF and high vagal tone. The athlete was able to return to competition 17 days after medical clearance for return to participation and 1 week later beat his indoor 60-m personal best. Conclusions: In this athlete, COVID-19 infection induced parasympathetic hyperactivity with subjective fatigue. This case report presents how performance capacity was only negatively influenced by a COVID-19 infection in the short term, with a quick and successful return to performance, thanks to state-of-the-art medical management. This highlights the importance of TL and HRV monitoring in return-to-participation and return-to-competition decisions.

Restricted access

Sean Healy

Fitness centers may be an ideal setting for physical activity, yet qualitative findings suggest social-level barriers constrain access for people with disabilities. To further test this, I employed an online message correspondence study to investigate the effect of impairment status on the responsiveness of a national sample of fitness centers to requests for services. Email requests were sent to 800 fitness centers, of which 200 were tailored to each of the four investigative conditions (i.e., control, vision loss, spinal cord injury, or being autistic). The odds of receiving a positive response were 40.5% lower for individuals with vision loss (p = .011) and 33.3% lower for individuals with spinal cord injury (p = .055), as compared with individuals without an impairment. Specifically, the odds of receiving a positive response for personal training were 58.8% lower among individuals with vision loss (p = .003) and 41.1% lower for individuals with spinal cord injury (p = .065).

Restricted access

Lindsay Eales and Donna L. Goodwin

Trauma is pervasive, embodied, and can be perpetrated or perpetuated by researchers, educators, and practitioners, including those within adaptive physical activity (APA). In this article, we highlight the need to address trauma within APA as a matter of access and justice. We share various conceptualizations of trauma from psychiatric, embodied, anti-pathologizing, and sociopolitical perspectives. Trauma-informed practice is introduced as a framework for creating safer, more inclusive programs and services, so we can recognize the impacts of trauma and affirm those who experience it. As the first step to a multistep trauma-informed process, our aim is to raise awareness of trauma and introduce resources for enacting trauma-informed practice. We also pose difficult questions about how we, as “helping” practitioners, researchers, and educators may be perpetuating or perpetrating harm and trauma, in particular sanism, within our profession. Ultimately, we invite readers to join us in reflection and action toward anti-pathologizing trauma-informed APA.

Restricted access

Viviene A. Temple

The COVID-19 pandemic is a worldwide crisis. It has been, and is, an extreme challenge for our health care and prevention systems, and for society as a whole. Among many facets of life, physical activity and sport has been heavily impacted. The aim of this viewpoint article is to highlight the effect of the COVID-19 pandemic on individuals with an intellectual disability, with a particular focus on physical activity and Special Olympics. Specific objectives are (a) to share what the literature reveals about the impact of COVID-19 on the health and well-being of individuals with an intellectual disability, (b) to examine what is known about the impact of the pandemic on physical activity of individuals with an intellectual disability, (c) to describe Special Olympics program responses during the pandemic, and (d) to recommend areas for future research.