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

Purpose: To investigate the relationship between physical fitness and repeated high-intensity effort (RHIE) ability in elite rugby union players, depending on playing position. Method: Thirty-nine players underwent a fitness testing battery composed of a body composition assessment, upper-body strength (1-repetition maximum bench press and 1-repetition maximum bench row), lower-body strength (6-repetition maximum back squat), and power (countermovement jump, countermovement jump with arms, and 20-m sprint), as well as aerobic fitness (Bronco test) and RHIE tests over a 1-week period. Pearson linear correlations were used to quantify relationships between fitness tests and the RHIE performance outcomes (total sprint time [TST] and percentage decrement [%D]). Thereafter, a stepwise multiple regression model was used to verify the influence of physical fitness measures on RHIE ability. Results: TST was strongly to very strongly associated to body fat (BF, r = .82, P < .01), the 20-m sprint (r = .86, P < .01), countermovement jump (r = −.72, P < .01), and Bronco test (r = .90, P < .01). These fitness outcomes were related to %D, with moderate to strong associations (.82 > ∣r∣ > .54, P < .01). By playing position, similar associations were observed in forwards, but RHIE ability was only related to the 20-m sprint in backs (r = .53, P < .05). The RHIE performance model equations were TST = 13.69 + 0.01 × BF + 0.08 × Bronco + 10.20 × 20 m and %D = −14.34 + 0.11 × BF +0.18 × Bronco − 9.92 × 20 m. These models explain 88.8% and 68.2% of the variance, respectively. Conclusion: Body composition, lower-body power, and aerobic fitness were highly related with RHIE ability. However, backs expressed a different profile than forwards, suggesting that further research with larger sample sizes is needed to better understand the fitness determinants of backs’ RHIE ability.

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Peter Leo, James Spragg, Iñigo Mujika, Andrea Giorgi, Dan Lorang, Dieter Simon, and Justin S. Lawley

Purpose: The aim of this study was to compare the power profile, internal and external workloads, and racing performance between U23 and professional cyclists and between varying rider types across 2 editions of a professional multistage race. Methods: Nine U23 cyclists from a Union Cycliste Internationale “Continental Team” (age 20.8 [0.9] y; body mass 71.2 [6.3] kg) and 8 professional cyclists (28.1 [3.2] y; 63.0 [4.6] kg) participated in this study. Rider types were defined as all-rounders, general classification (GC) riders, and domestiques. Data were collected during 2 editions of a 5-day professional multistage race and split into the following 4 categories: power profile, external and internal workloads, and race performance. Results: The professional group, including domestiques and GC riders, recorded higher relative power profile values after certain amounts of total work (1000–3000 kJ) than the U23 group or all-rounders (P ≤ .001–.049). No significant differences were found for external workload measures between U23 and professional cyclists, nor among rider types. Internal workloads were higher in U23 cyclists and all-rounders (P ≤ .001–.043) compared with professionals, domestiques, and GC riders, respectively. The power profile significantly predicted percentage general classification and Union Cycliste Internationale points (R 2 = .90–.99), whereas external and internal workloads did not. Conclusion: These findings reveal that the power profile represents a practical tool to discriminate between professionals and U23 cyclists as well as rider types. The power profile after 1000 to 3000 kJ of total work could be used by practitioners to evaluate the readiness of U23 cyclists to move into the professional ranks, as well as differentiate between rider types.

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Stefan Altmann, Rainer Neumann, Sascha Härtel, Alexander Woll, and Martin Buchheit

Purpose: To assess the value of monitoring changes in fitness in professional soccer players, using changes in heart rate at submaximal intensity (HR12km/h) over the velocity at a lactate concentration of 4 mmol/L (v4mmol/L). The authors reexamined (1) a range of threshold magnitudes, which may improve detecting substantial individual changes and (2) the agreement between changes in these 2 variables. Methods: On at least 2 occasions during different moments of the season, 97 professional soccer players from Germany (first, second, and fourth division) completed an incremental test to determine HR12km/h and v4mmol/L. Optimal thresholds for changes in HR12km/h and v4mmol/L were assessed, using various methods (eg, smallest worthwhile change + typical error [TE], successive reiterations approach). Agreement between both variable changes was examined for the whole sample (225 comparisons), 4 different subgroups (depending on the moment of the season), and in an individual over 6 years (n = 23 tests). Results: Changes of 4.5% and 6.0% for HR12km/h and v4mmol/L, respectively, were rated as optimal to indicate substantial changes in fitness. Depending on the (sub)groups analyzed, these thresholds yielded 0% to 2% full mismatches, 22% to 38% partial agreements, and 60% to 78% full agreements in terms of fitness change interpretation between both variables. Conclusions: When lactate sampling during incremental tests is not possible, practitioners willing to monitor adult professional soccer players’ (Germany; first, second, and fourth division) training status can confidently implement short, 3-minute submaximal runs, with 4.5% changes in HR12km/h being indicative of true substantial fitness changes, with 60% to 78% accuracy. Future studies should investigate the potential role of confounding factors of HR12km/h to improve changes in fitness prediction.

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Genevieve F. Dunton, Daniel Chu, Christine H. Naya, Britni R. Belcher, and Tyler B. Mason

Background: Psychological stress has adverse effects on health-related behaviors, yet longitudinal research is lacking. Research examined how children’s and mothers’ perceived stress are associated with children’s physical activity and sedentary behavior trajectories across 3 years. Methods: Mothers and their children (N = 186 dyads; 8–12 y at baseline, 57% Hispanic) completed 6 assessments across 3 years. Children and mothers self-reported perceived stress using the Stress in Children Scale and Perceived Stress Scale, respectively. Children’s moderate to vigorous physical activity (MVPA) and sedentary behavior were assessed using accelerometers. Mixed models examined interactions of mothers’ and children’s perceived stress by time elapsed in the study on children’s MVPA and sedentary behavior. Results: The perceived stress × time elapsed interactions were significant for children’s MVPA and sedentary behavior (Ps < .05). Higher average perceived stress in mothers was associated with greater decreases in children’s MVPA and increases in children’s sedentary behavior. The child stress × time elapsed interactions was significant for children’s MVPA (P < .05) but not sedentary behavior. Higher average perceived stress in children was associated with smaller decreases in children’s MVPA. Conclusion: Interventions to promote physical activity and reduce screen time in children should mitigate the effects of psychological stress, especially among mothers, on these behaviors.

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Hamid Reza Bokaeian, Fateme Esfandiarpour, Shahla Zahednejad, Hossein Kouhzad Mohammadi, and Farzam Farahmand

In this study, the effects of an exercise therapy comprising yoga exercises and medial-thrust gait (YogaMT) on lower-extremity kinetics, pain, and function in patients with medial knee osteoarthritis were investigated. Fifty-nine patients were randomly allocated to three treatment groups: (a) the YogaMT group practiced yoga exercises and medial thrust gait, (b) the knee-strengthening group performed quadriceps- and hamstring-strengthening exercises, and (c) the treadmill walking group practiced normal treadmill walking in 12 supervised sessions. The adduction and flexion moments of the hip, knee, and ankle; pain intensity; and 2-min walking test were assessed before and after treatment and at 1-month follow-up. The YogaMT group experienced a significant reduction in knee adduction moment. All groups showed significant improvement in pain and function. The YogaMT may reduce medial knee load in patients with knee osteoarthritis in the short term. A larger clinical trial is required to investigate the long-term outcomes of this intervention.

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Otávio Luis Piva da Cunha Furtado, Mikko Häyrinen, Isabela dos Santos Alves, Leonardo Travitzki, and Márcio Pereira Morato

The authors’ purpose was to examine the factors associated with penalty outcomes of male elite goalball. A total of 122 video-recorded matches from two Paralympic Games (i.e., 2012 and 2016) and the 2014 Goalball World Championship were assessed using notational analysis. Individual (n = 2), situational (n = 4), and performance variables (n = 7) were analyzed with good strength of agreement for intra- and interrater kappa index values. Their results showed that penalties play a very important role in the final score, composing around 25% of total goals in elite goalball matches. Winners were awarded on average with 62% of penalties and had 66% effectiveness compared with losers (31% and 53%) or drawers (8% and 52%). Based on the authors’ findings, penalty takers should direct their throws at specific target sectors on the court, which could increase their rate of success to over 80%.

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S. Morgan Hughey, Marilyn E. Wende, Ellen W. Stowe, Andrew T. Kaczynski, Jasper Schipperijn, and J. Aaron Hipp

Background: Neighborhood parks are recognized as important spaces for facilitating physical activity (PA); however, it remains unclear how the frequency of park use is associated with PA. The purpose of this study was to examine associations between minutes of moderate to vigorous PA and multiple park use indicators: (1) use of a neighborhood park, (2) unique number of neighborhood parks used, and (3) frequency of neighborhood park use. Methods: Adults were surveyed from 4 US cities (Brooklyn, NY; Greenville County, SC; Raleigh, NC; and Seattle, WA). Using a map-based survey platform, participants indicated all neighborhood parks they used and the frequency of use in the past 30 days. Participants self-reported their weekly moderate to vigorous PA. Quantile regression was used to examine associations between PA and park use indicators. Results: Of all respondents (N = 360), 60% indicated visiting a neighborhood park in the past 30 days, with an average of about 13 total neighborhood park visits (SD = 17.5). Significant, positive associations were found between moderate to vigorous PA and both unique neighborhood park visits and total number of neighborhood parks visits. Conclusions: Frequency of park visitation is associated with PA among US adults. Ensuring equitable and safe access to neighborhood parks has the potential for population-level PA health benefits.

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Joanna M. Auger and Nancy L.I. Spencer

Justifications for access to physical activity for people who experience disability tend to focus on the health benefits associated with a medical model of disability. The result is often programs that are segregated and impairment-focused, with limited access to integrated settings that are also potentially inclusive. In this instrumental case study, the authors engaged 20 participants with and without impairment from an adult integrated indoor cycling program to explore what contributed to meaningful and inclusive experiences in this setting. Data were generated through semistructured interviews and reflective notes. Thematic analysis led to three themes: (a) “just going to a spin class” (b) “seamless”? and (c) “deliberate community.” Using a relational ethics framework, the findings are discussed with regard to their potential to inform the development of integrated and inclusive physical activity programs, with emphasis on program structure and instructor reflexivity and training.

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Russell R. Pate, Marsha Dowda, Ruth P. Saunders, Natalie Colabianchi, Morgan N. Clennin, Kerry L. Cordan, Geena Militello, Agnes Bucko, Dwayne E. Porter, and Wm. Lynn Shirley

Background: The prevalence of childhood obesity is higher in economically and socially deprived areas. Higher levels of physical activity reduce the risk of excessive weight gain in youth, and research has focused on environmental factors associated with children’s physical activity, though the term “physical activity desert” has not come into wide use. Methods: This exploratory study operationalized the term “physical activity desert” and tested the hypothesis that children living in physical activity deserts would be less physically active than children who do not. A cross-sectional study design was applied with 992 fifth-grade students who had provided objectively measured physical activity data. Five of 12 possible elements of the built environment were selected as descriptors of physical activity deserts, including no commercial facilities, no parks, low play spaces, no cohesion, and the presence of incivilities. Results: Univariate and multivariate analyses showed that only the absence of parks was associated with less physical activity in children. Conclusion: Children living in a “no park” zone were less active than their counterparts who lived near a park. This study contributes preliminary conceptual and operational definitions of “physical activity desert.” Future studies of physical activity deserts should be undertaken in larger and more diverse samples.

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Heidi Skantz, Timo Rantalainen, Laura Karavirta, Merja Rantakokko, Lotta Palmberg, Erja Portegijs, and Taina Rantanen

The authors examined whether accelerometer-based free-living walking differs between those reporting walking modifications or perceiving walking difficulty versus those with no difficulty. Community-dwelling 75-, 80-, or 85-year-old people (N = 479) wore accelerometers continuously for 3–7 days, and reported whether they perceived no difficulties, used walking modifications, or perceived difficulties walking 2 km. Daily walking minutes, walking bouts, walking bout intensity and duration, and activity fragmentation were calculated from accelerometer recordings, and cut points for increased risk for perceiving walking difficulties were calculated using receiver operating characteristic analysis. The authors’ analyses showed that accumulating ≤83.1 daily walking minutes and walking bouts duration ≤47.8 s increased the likelihood of reporting walking modifications and difficulties. Accumulating walking bouts ≤99.4 per day, having walking bouts ≤0.119 g intensity, and ≥0.257 active to sedentary transition probability fragmented activity pattern were associated only with perceiving walking difficulties. The findings suggest that older people’s accelerometer-based free-living walking reflects their self-reported walking capability.