Foot structure and kinematics have long been considered as risk factors for foot and lower-limb running injuries. The authors aimed at investigating foot joint kinetics to unravel their receptive and propulsive characteristics while running barefoot, both with rearfoot and with midfoot striking strategies. Power absorption and generation occurring at different joints of the foot in 6 asymptomatic adults were calculated using both a 3-segment and a 4-segment kinetic model. An inverse dynamic approach was used to quantify mechanical power. Major power absorption and generation characteristics were observed at the ankle joint complex as well as at the Chopart joint in both the rearfoot and the midfoot striking strategies. The power at the Lisfranc joint, quantified by the 4-segment kinetic model, was predominantly generated in both strategies, and at the toes, it was absorbed. The overall results show a large variability in the receptive and propulsive characteristics among the analyzed joints in both striking strategies. The present study may provide novel insight for clinical decision making to address foot and lower-limb injuries and to guide athletes in the adoption of different striking strategies during running.
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Kevin Deschamps, Giovanni Matricali, Maarten Eerdekens, Sander Wuite, Alberto Leardini and Filip Staes
Lisa A. Kihl and Vicki Schull
The meaning and nature of athlete representation in sport governance is broad and goes beyond formalistic delegate models and voting rights accounts. This article explores the meaning and nature of representation in the context of intercollegiate sport governance. Interviews were conducted with intercollegiate athlete representatives and athlete representative administrative advisors to gain an understanding of how and why athlete representatives carried out their roles. Findings revealed that the meaning and motivations of athlete representation were based on the institutionalized deliberative democratic governance system. Representation meant standing and acting for the power of the athlete voice and having the capacity to generate the athlete voice into legislation and decision making. The performative role of representatives involved self-accountability, where they accepted responsibility to engage in a deliberative process of collective decision making. Implications for practice and future research on athlete representation in a deliberative democratic sport governance system are presented.
Bruno P. Melo, Débora A. Guariglia, Rafael E. Pedro, Dennis A. Bertolini, Solange de Paula Ramos, Sidney B. Peres and Solange M. Franzói de Moraes
Background: Combined exercise (CE) has been recommended for individuals living with HIV/AIDS (ILWHA) under antiretroviral therapy. However, depending on the intensity and duration, physical exercise may occasionally increase inflammatory parameters and reduce immunological responses that if not reversed, cause health injury specifically in this population. Information about immunological and hormonal responses after CE in ILWHA has not been completely elucidated. Therefore, the aim is to verify the acute effects of CE on cortisol, testosterone, immunoglobulin A, and pro-inflammatory and anti-inflammatory cytokines over 24 hours in ILWHA. Methods: Noninfected individuals and ILWHA undergone 5 sessions of CE prior to the acute assessment session. Seventy-two hours after the last session, the subjects were submitted to one session of CE (aerobic exercise: 25 min at 60–70% reserve heart rate and resistance exercise: 3 sets of 15 maximum repetitions of 6 exercises). Saliva samples were collected before, immediately, 6 and 24 hours after CE. Results: CE reduced cortisol (6 h: 2.54 [0.58] vs 0.65 [0.22] pg·mL−1; P = .02), increased testosterone (all moments) and immunoglobulin A levels (24 h: 255.3 [44.7] vs 349.2 [41.9] μm·mL−1; P = .01) without significant difference in cytokines levels in ILWHA. Conclusion: CE modulates cortisol, testosterone, and immunoglobulin A levels without the change in immunological parameters in ILWHA.
Cameron T. Gibbons, Polemnia G. Amazeen and Aaron D. Likens
Variability is commonly observed in complex behavior, such as the maintenance of upright posture. The current study examines the value added by using nonlinear measures of variability to identify dynamic stability instead of linear measures that reflect average fluctuations about a mean state. The largest Lyapunov exponent (λ1) and SD were calculated on mediolateral movement as participants performed a sit-to-stand task on a stable and unstable platform. Both measures identified changes in movement across postures, but results diverged when participants stood on the unstable platform. Large SD indicated an increase in movement variability, but small λ1 identified those movements as stable and controlled. The results suggest that a combination of linear and nonlinear analyses is useful in identifying the proportion of observed variability that may be attributed to structured, controlled sources. Nonlinear measures of variability, like λ1, can further be used to make predictions about transitions between stable postures and to identify a system’s resistance to disruption from external perturbations. Those features make nonlinear analyses highly applicable to both human movement research and clinical practice.
Estela Farías-Torbidoni and Demir Barić
Background: Protected areas are important attractions for promoting healthy life habits. Consequently, to date, a number of studies have examined the association between visitors’ characteristics and physical activities. However, little is known about the specific users inclined exclusively to have sedentary behavior during a visit. Thus, using the Alt Pirineu Natural Park (Spain) as a case study, the aim of this study is to determine the influence of sociodemographic, trip, motivational, and opinion descriptors on the likelihood of participating in sedentary behavior while visiting a protected natural area. Methods: The data used were randomly collected from visitors through an onsite structured questionnaire (N = 628). Results: Metabolic equivalent consumption was used to empirically distinguish the sedentary (22.6%) from the active (77.4%) visitor groups. A logistic regression analysis indicated that the trip and motivational descriptors explained the highest degree of the overall variation in reporting sedentary behavior. Conclusion: The study contributed to documenting the information about visitors’ behavior in protected areas, and the findings may aid park managers in developing effective management strategies for promoting and enhancing physical activity in protected natural areas.
Jon Welty Peachey, Nico Schulenkorf and Ramon Spaaij
Erin Morris, Ryan Vooris and Tara Q. Mahoney
Female students are underrepresented within university sport management programs. Because of the concept of the “chilly climate,” the underrepresentation may impact their experiences as students and their opportunities inside and outside of the classroom. The purpose of this study was to gain a better understanding of female students’ experiences within this male-dominated major. Three qualitative focus groups with female sport management students were conducted. The results found the female students had strategies to overcome barriers, a firm understanding of the reality of the gender dynamic within sport management, and an awareness of the importance of networking to succeed in the major. These findings may help sport management programs better support their female students through initiatives like women-in-sport-management clubs.
Sungho Cho, J. Lucy Lee, June Won and Jong Kwan (Jake) Lee
Under the federal trademark law, owners of famous sport trademarks may bring legal claims against unauthorized users of their marks under the infringement and dilution theory. Although the rationale of trademark infringement has been supported by various notions of consumer psychology and law and economics, the theory of dilution has been criticized for the lack of empirical support. This study investigated whether the junior use of major sport trademarks would have dilutive effects on the senior marks in financial terms. The study employed the contingent valuation method, a technique designed to estimate the economic values of nonpecuniary assets such as trademarks. A total of 140 subjects were exposed to dilutive information while they purchased sport brand merchandise. A series of pre- and posttests revealed that moderately famous sport trademarks suffered dilutive harm from junior use, whereas exceptionally famous marks were immune to the dilutive effects. Theoretical and practical implications were discussed.
Jordan Andre Martenstyn, Lauren Powell, Natasha Nassar, Mark Hamer and Emmanuel Stamatakis
Background: Previous epidemiological studies examining the association between physical activity (PA) and mortality risk have measured absolute PA intensity using standard resting metabolic rate reference values that fail to consider individual differences. This study compared the risk of all-cause and cardiovascular mortality between absolute and corrected estimates of PA volume. Methods: 49,982 adults aged ≥40 years who participated in the Health Survey for England and Scottish Health Survey in 1994–2008 were included in our study. PA was classified as absolute or corrected metabolic equivalent (MET)-hours per week, taking participant’s weight, height, age, and sex into account. Cox regression models were used to examine the association between absolute and corrected PA volumes and all-cause and cardiovascular mortality. Results: The authors found no difference in the association between levels of PA and risk of all-cause and cardiovascular mortality for absolute and corrected MET-hours per week, although there was a consistent decrease in mortality risk with increasing PA. There was no difference in mortality when analyses were stratified by sex, age, and body mass index. Conclusions: The association between PA volume and risk of mortality was similar regardless of whether PA volume was estimated using absolute or corrected METs. There is no empirical justification against the use of absolute METs to estimate PA volume from questionnaires.
Jeanette Gustat, Christopher E. Anderson, Keelia O’Malley, Tian Hu, Rachel G. Tabak, Karin Valentine Goins, Cheryl Valko, Jill S. Litt and Amy A. Eyler
Background: To assess how perceptions of the community built environment influence support for community policies that promote physical activity (PA). Methods: A national cross-sectional survey assessed perceptions of the local built environment and support of community policies, including school and workplace policies, promoting PA. A random digit–dialed telephone survey was conducted in US counties selected on Behavioral Risk Factor Surveillance System data for high or low prevalence of obesity and inactivity. A total of 1208 subjects were interviewed, 642 from high-prevalence counties and 566 from low-prevalence counties. Analyses were stratified by county prevalence of obesity and inactivity (high or low). Linear models adjusted for covariates were constructed to assess the influence of built environment perceptions on policy support. Results: Perception of more destinations near the residence was associated with increased support for community policies that promote PA, including tax increases in low-prevalence (obesity and inactivity) counties (P < .01). Positive perception of the workplace environment was associated (P < .001) with increased support for workplace policies among those in high-, but not low-, prevalence counties. Conclusions: Support for community policies promoting PA varies by perception of the built environment, which has implications for policy change.