The development of composite material poles since 1960 has played a prominent part in performance improvement in pole-vaulting. Previous studies devoted to pole-vaulting models were based on constant mechanical characteristics. It is thus necessary to identify the local bending rigidities of the pole to build realistic pole-vaulting models. Updating methods developed for dynamic structure studies allow us to describe local mechanical characteristics. These methods are based on the comparison between experimental results and those determined numerically by finite element models. This study presents an adaptation of these methods to determine the local bending rigidities of the pole. The updating technique is validated by a deflection test of a homogeneous beam. Then, a study of the model sensitivity is carried out to investigate the procedure robustness. Finally, the updating method is applied to an old design pole and to a recent one. The results obtained vary greatly from one pole to the other; they highlight the evolutions in pole design.
Julien Morlier, Michel Mesnard and Mariano Cid
Andre M. Andrijiw and Craig G. Hyatt
In an attempt to understand the lived experiences of those individuals who grew up within the fan region of one professional hockey team yet chose instead to identify with a nonlocal alternative, the authors interviewed 20 Ontario (Canada) based fans of distant National Hockey League teams. Utilizing Brewer’s (1991, 2003) theory of optimal distinctiveness to examine the stories of participants, it was found that these fans maintained their team allegiances over time because doing so allowed them to achieve feelings of both uniqueness and belongingness. Sport managers can help facilitate feelings of belongingness by utilizing various communication and marketing strategies to better recognize and include their distant fans. Such strategies should ultimately result in the strengthening of the fan-team bond.
Amber E. Rowell, Robert J. Aughey, Will G. Hopkins, Andrew M. Stewart and Stuart J. Cormack
Objective measures of recovery from football match play could be useful for assessing athletes’ readiness to train, if sensitive to preceding match load.
To identify the sensitivity of countermovement-jump (CMJ) performance and concentration of salivary testosterone and cortisol relative to elite football match load.
CMJ performance and salivary hormones were measured in 18 elite football players before (27, 1 h) and after (0.5, 18, 42, 66, 90 h) 3 consecutive matches. Match load was determined via accelerometer-derived PlayerLoad and divided into tertiles. Sensitivity of CMJ performance and hormone concentrations to match load was quantified with t statistics and magnitude-based inferences (change in mean as % ± 90% confidence interval) derived with a linear mixed model.
Jump height was reduced in medium and high load at 0.5 h (10% ± 7% and 16% ± 8%) and 18 h (7% ± 4% and 9% ± 5%) postmatch. There was a 12% ± 7% reduction in ratio of flight time to contraction time (FT:CT) in high load at 0.5 h post, with reductions in medium and high load at 18 h. Reductions in FT:CT persisted at later postmatch time points than changes in jump height. Increased cortisol (range 55–165%) and testosterone (range 17–20%) were observed in all match loads at 0.5 h post, with individual variability thereafter.
Measures of CMJ performance and hormonal concentrations were sensitive to levels of A League football match load. Although jump height was reduced immediately postmatch, FT:CT provided a more sensitive measure of recovery. Football match play induces an acute hormonal response with substantial individual variability thereafter.
David R. Howell, Thomas A. Buckley, Brant Berkstresser, Francis Wang and William P. Meehan III
The purpose of this study was to identify the rate of abnormal single-task and dual-task gait performance following concussion compared to uninjured controls using previously established normative reference values. The authors examined athletes with a concussion (n = 54; mean age = 20.3 [1.1] y, 46% female, tested 2.9 [1.5] d postinjury), and healthy controls were tested during their preseason baseline examination (n = 60; mean age = 18.9 [0.7] y, 37% female). Participants completed an instrumented single-/dual-task gait evaluation. Outcome variables included average walking speed, cadence, and step length. A significantly greater number of those with concussion walked with abnormal dual-task gait speed compared with the control group (56% vs 30%, P = .01). After adjusting for potential confounding variables (age, concussion history, symptom severity, and sleep), concussion was associated with lower dual-task gait speed (β = −0.150; 95% confidence interval [CI] = −0.252 to −0.047), cadence (β = −8.179; 95% CI = −14.49 to −1.871), and stride length (β = −0.109; 95% CI = −0.204 to −0.014). Although group analyses indicated that those with a concussion performed worse on single-task and dual-task gait compared with controls, a higher rate of abnormal gait was detected for the concussion group compared with the control group for dual-task gait speed only. Dual-task gait speed, therefore, may be considered as a measure to compare against normative values to detect postconcussion impairments.
Stephen M. Paridon, Steven B. Wolfe, Chau P. Lee, Michael A. Nigro and William W. Pinsky
To determine whether defects of skeletal muscle oxidative phosphorylation can be differentiated from other causes of skeletal muscle weakness by aerobic responses to exercise, 10 patients with oxidative phosphorylation abnormalities (n = 5) or defects of contractile element apparatus or peripheral neuropathy (n = 5) underwent bicycle exercise testing. Results were compared with 16 healthy control subjects. The response of oxygen consumption to work rate and ventilatory threshold were significantly reduced in the oxidative phosphorylation group when compared to subjects with other causes of muscle weakness and the control group. Exercise testing appears to be useful in distinguishing patients with defects of oxidative phosphorylation from those with other causes of skeletal muscle weakness.
Felipe Alvim, Lucenildo Cerqueira, Aluízio D’Affonsêca Netto, Guilherme Leite and Adriane Muniz
This study involved a comparison of 5 kinematic-based algorithms to detect heel strike (HS) and toe-off (TO) events during human locomotion at different speeds. The objective was to assess how different running and walking speeds affect contact event determination during treadmill locomotion. Thirty male runners performed walking at 5 km/h and running at 9, 11, and 13 km/h on a treadmill. A kinematic system was used to capture the trajectories of 2 retro-reflective markers placed at the subject’s right heel and second metatarsal. A footswitch device was used to determine the “true” times of HS and TO compared with 5 kinematic-based algorithms. The results of the current study illustrated that speed influences the HS error in the vertical position and horizontal velocity algorithms, and the TO error in the vertical position and horizontal velocity algorithms. This difference was found in the transition from walking to running; however, higher running speeds did not affect the error estimation. Higher accuracy was found with combined algorithms, namely, one using vertical acceleration and position and another using horizontal and vertical position with no influence from different locomotion speeds. Therefore, these algorithms are recommended in studies where speed is self-selected because they work well for a broad range of locomotion velocities.
Tara K. Scanlan, David G. Russell, Larry A. Scanlan, Tatiana J. Klunchoo and Graig M. Chow
Following a thorough review of the current updated Sport Commitment Model, new candidate commitment sources for possible future inclusion in the model are presented. They were derived from data obtained using the Scanlan Collaborative Interview Method. Three elite New Zealand teams participated: amateur All Black rugby players, amateur Silver Fern netball players, and professional All Black rugby players. An inductive content analysis of these players’ open-ended descriptions of their sources of commitment identified four unique new candidate commitment sources: Desire to Excel, Team Tradition, Elite Team Membership, and Worthy of Team Membership. A detailed definition of each candidate source is included along with example quotes from participants. Using a mixed-methods approach, these candidate sources provide a basis for future investigations to test their viability and generalizability for possible expansion of the Sport Commitment Model.
Ben Larkin and Janet S. Fink
Team identification—loosely defined as a psychological connection to a sport team ( Wann, 2006 )—has been covered extensively in sport management literature. For example, a wealth of research has been put into understanding both the outcomes of team identification (e.g., Branscombe & Wann, 1992
Stephen L. Shapiro, Lynn L. Ridinger and Galen T. Trail
The growth of college sport over the last several years, combined with increased competition for the sport consumer dollar, has created a need to understand spectator consumption behavior. In addition, the impact of a new football program can generate interest that influences future spectator spending decisions. Using identity theory as a framework, the current study examined the differential effects of past sport consumer behaviors on various future sport consumer intentions within the context of a new college football program. Consumption intentions included attendance, sponsor support, and merchandise purchases. Furthermore, this investigation helped to determine how much variance past behaviors would explain in behavioral intentions after controlling for nine points of attachment. Data were collected from spectators of a Football Championship Subdivision (FCS) football program located in the Mid-Atlantic region. The findings suggest past behavior predicted future intentions; however, the amount of variance explained varied dramatically depending on specific past behaviors and points of attachment. These results can help sport marketers develop strategies to capitalize on the interest generated through new athletic programs.
Fagner Serrano, Jana Slaght, Martin Sénéchal, Todd Duhamel and Danielle R. Bouchard
Many international agencies recommend using 40% of VO2reserve to individually prescribe moderate aerobic intensity to achieve health benefits. Few studies have evaluated the walking cadence needed to reach that intensity for older adults. A total of 121 apparently healthy adults with an average age of 69 and an average VO2peak of 24.1 ± 6.7 ml/kg/min (women) and 28.9 ± 9.1 ml/kg/min (men) were studied. Walking cadence at moderate intensity was established when participants reached 40% of VO2reserve on an indoor flat surface using a portable metabolic cart. Other clinical variables potentially associated with walking cadence were collected to create a clinical algorithm. Mean walking cadence to reach moderate intensity was 115 ± 10 steps per minute. The best algorithm to predict the walking cadence needed to reach moderate intensity in this sample was 113.6–0.23 (body weight in kg) + 0.21 (self-selected walking cadence in steps per minute).