Purpose: Pacing, or the distribution of energy expenditure, is particularly important in swimming; however, there is limited research examining pacing profiles in long-distance freestyle events. This study aimed to characterize the pacing profiles of elite male 1500-m freestyle swimmers using a novel method to provide a detailed analysis of different race segments. Methods: The race data for 327 male 1500-m freestyle long-course races between 2010 and 2019 were analyzed retrospectively. The raw 50-m split times for each lap were converted to a percentage of overall race time. The races were classified as a fast-, average-, or slow-start strategy (laps 1–2); as an even, negative, or positive pacing strategy (laps 3–28); and as a fast-, average-, or slow-finish strategy (laps 29–30) to give an overall pacing profile. Results: Slow- and average-start strategies were associated with faster overall 1500-m times than a fast-start strategy (mean = −21.2 s; 90% confidence interval, −11.4 to −32.3 s, P = .00). An even pacing strategy in laps 3 to 28 yielded faster overall 1500-m times than a positive pacing strategy (−8.4 s, −3.9 to −13.0 s, P = .00). The overall 1500-m times did not differ substantially across the finish strategies (P = .99). The start strategy differed across age groups and nationalities, where younger swimmers and swimmers from Australia and Great Britain typically spent a lower percentage of race time in laps 1 to 2 (faster start strategy; −0.10%, −0.01% to −0.23%, P ≤ .02). Conclusion: Adopting a relatively slower start strategy helps conserve energy for the latter stages of a 1500-m freestyle race.
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Katie E. McGibbon, David B. Pyne, Laine E. Heidenreich and Robin Pla
Dionne A. Noordhof, Sjur J. Øfsteng, Linnea Nirenberg, Daniel Hammarström, Joar Hansen, Bent R. Rønnestad and Øyvind Sandbakk
Performance-determining variables are usually measured from a rested state and not after prolonged exercise, specific to when athletes compete for the win in long-distance events. Purpose: (1) To compare cross-country skiing double-poling (DP) performance and the associated physiological and biomechanical performance-determining variables between a rested state and after prolonged exercise and (2) to investigate whether the relationship between the main performance-determining variables and DP performance is different after prolonged submaximal DP than when tested from a rested state. Methods: Male cross-country skiers (N = 26) performed a blood lactate profile test and an incremental test to exhaustion from a rested state on day 1 (D1; all using DP) and after 90-minute submaximal DP on day 2 (D2). Results: The DP performance decreased following prolonged submaximal DP (D1: peak speed = 15.33–20.75 km·h−1, median = 18.1 km·h−1; D2: peak speed = 13.68–19.77 km·h−1, median = 17.8 km·h−1; z = −3.96, P < .001, effect size r = −.77), which coincided with a reduced submaximal gross efficiency and submaximal and peak cycle length, with no significant change in peak oxygen uptake (P = .26, r = .23). The correlation coefficient between D1 cycle length at 12 km·h−1 and D2 performance is significantly smaller than the correlation coefficient between D2 cycle length at 12 km·h−1 and D2 performance (P = .033), with the same result being found for peak cycle length (P < .001). Conclusions: The reduced DP performance after prolonged submaximal DP coincided with a reduced submaximal gross efficiency and shorter peak cycle length. The results indicate that performance-determining variables could be determined after prolonged exercise to gain more valid insight into long-distance DP performance.
Stefanie N. Foster, Michael D. Harris, Mary K. Hastings, Michael J. Mueller, Gretchen B. Salsich and Marcie Harris-Hayes
Context: The authors hypothesized that in people with hip-related groin pain, less static ankle dorsiflexion could lead to compensatory hip adduction and contralateral pelvic drop during step-down. Ankle dorsiflexion may be a modifiable factor to improve ability in those with hip-related groin pain to decrease hip/pelvic motion during functional tasks and improve function. Objective: To determine whether smaller static ankle dorsiflexion angles were associated with altered ankle, hip, and pelvis kinematics during step-down in people with hip-related groin pain. Design: Cross-sectional Setting: Academic medical center. Patients : A total of 30 people with hip-related groin pain (12 males and 18 females; 28.7 [5.3] y) participated. Intervention: None. Main Outcome Measures: Weight-bearing static ankle dorsiflexion with knee flexed and knee extended were measured via digital inclinometer. Pelvis, hip, and ankle kinematics during forward step-down were measured via 3D motion capture. Static ankle dorsiflexion and kinematics were compared with bivariate correlations. Results: Smaller static ankle dorsiflexion angles were associated with smaller ankle dorsiflexion angles during the step-down for both the knee flexed and knee extended static measures. Among the total sample, smaller static ankle dorsiflexion angle with knee flexed was associated with greater anterior pelvic tilt and greater contralateral pelvic drop during the step-down. Among only those who did not require a lowered step for safety, smaller static ankle dorsiflexion angles with knee flexed and knee extended were associated with greater anterior pelvic tilt, greater contralateral pelvic drop, and greater hip flexion. Conclusions: Among those with hip-related groin pain, smaller static ankle dorsiflexion angles are associated with less ankle dorsiflexion motion and altered pelvis and hip kinematics during a step-down. Future research is needed to assess the effect of treating restricted ankle dorsiflexion on quality of motion and symptoms in patients with hip-related groin pain.
Hannah W. Tucker, Emily R. Tobin and Matthew F. Moran
Context: Performance on single-leg hopping (SLH) assessments is commonly included within return-to-sport criteria for rehabilitating athletes. Triaxial accelerometers have been used to quantify impact loading in a variety of movements, including hopping; however, they have never been attached to the tibia during SLH, and their method of fixation has not been investigated. Objective: The purpose of this study was to quantify triaxial accelerations and evaluate the influence of the fixation method of a lightweight inertial measurement unit (Blue Trident) mounted to the tibia during SLH performance. Design: Single cohort, repeated-measures experimental design. Participants: Sixteen healthy participants (10 females and 6 males; 20 [0.9] y; 1.67 [0.08] m; 66.0 [8.5] kg) met the inclusion criteria, volunteered, and completed this study. Interventions: Participants performed 2 sets of 3 SLH trials with an inertial measurement unit (1500 Hz) fixated to the tibia, each set with 1 of 2 attachment methods (double-sided tape [DST] with athletic tape and silicon strap [SS] with Velcro adhesion). Main Outcome Measures: Hop distance, peak tibial acceleration (PTA), time to PTA, and the acceleration slope were assessed during each hop landing. Results: Repeated-measures analysis of variance determined no significant effect of the attachment method on hop metrics (P = .252). Across 3 trials, both fixation methods (DST and SS) had excellent reliability values (intraclass correlation coefficient: .868–.941) for PTA and acceleration slope but not for time to PTA (intraclass correlation coefficient: .397–.768). The PTA for DST (27.22 [7.94] g) and SS (26.21 [10.48] g) was comparable and had a moderate, positive relationship (DST: r = .72, P < .01; SS: r = .77, P < .01) to SLH distance. Conclusions: Tibial inertial measurement units with triaxial accelerometers can reliably assess PTA during performance of the SLH, and SS is a viable alternative tibial attachment to DST.
Nicholas G. Gomez, Kelton K. Gubler, Kenneth Bo Foreman and Andrew S. Merryweather
The factors that contribute to the difficulties persons with Parkinson Disease (PwPD) have when negotiating transitions in walking surfaces are not completely known. The authors investigated if PwPD adjusted their step characteristics when negotiating a familiar outdoor surface transition between synthetic concrete and synthetic turf. Force plate and motion capture data were collected for 10 participants with mild to moderate Parkinson disease and 5 healthy older control participants ambulating bidirectionally across the transition between synthetic concrete and synthetic turf. Between groups, PwPD had a significantly higher minimum toe clearance (P = .007) for both directions of travel compared with the healthy control group. Within groups, PwPD significantly increased their hip (P < .001) and ankle (P = .016) range of motion walking from concrete to turf, while the healthy control participants significantly increased their minimum toe clearance (P = .013), margin of stability (P = .019), hip (P < .001) and ankle (P = .038) range of motion, and step length (P < .001). Walking from turf to concrete, both the Parkinson disease group (P = .014) and the healthy control group (P < .001) increased their knee range of motion. Both groups adjusted their step characteristics when negotiating known surface transitions, indicating that surface transitions result in step changes regardless of health status. However, PwPD exhibited overcompensations, particularly in their minimum toe clearance.
Leah K. May and Matthew D. Curtner-Smith
Purpose: To determine the impact of two preservice teachers’ value orientations on their interpretation and delivery of the skill themes approach. Method: The short form of the value orientations inventory and five qualitative techniques were used to collect data. Participants’ value orientations inventory profiles were illustrated graphically. Interpretive data were analyzed using analytic induction and constant comparison. Findings: Results from the short form of the value orientations inventory indicated that Meagan prioritized social responsibility, learning process, and disciplinary mastery, while Jared favored social responsibility, self-actualization, and ecological integration. Qualitative data largely supported these value orientation profiles and indicated that the preservice teachers’ approaches to teaching skill themes differed and were influenced by their pedagogical beliefs. Moreover, qualitative data illustrated how Meagan’s and Jared’s value orientations and interpretations of the skill themes approach had changed and developed. Conclusions: These findings emphasize the importance of preservice teachers engaging in philosophical reflection on the connections between their beliefs and their interpretations of curriculum models.
Jason Laurendeau, Tiffany Higham and Danielle Peers
In October 2018, Canadian retailer Mountain Equipment Co-op publicly asked, “Do white people dominate the outdoors?” and acknowledged that their representations were “part of [a] problem.” Relying on Ahmed’s theorizations of diversity work, this paper offers an intersectional interrogation of Mountain Equipment Co-op’s (MEC’s) commitment to including more “diversity” in their representations and considers how both MEC’s statement and their early efforts to diversify simultaneously efface the gendered, ableist, fatphobic, settler colonial and racist structuring of “the outdoors” both in MEC’s practices and in “Canada” more broadly. Our analysis highlights how MEC’s practices continue to reflect and reproduce the appropriation of wilderness for a narrow range of bodies.
Joon Ho Lim, Leigh Anne Donovan, Peter Kaufman and Chiharu Ishida
To examine how the level of humility expressed through athletes’ social media postings and post volume is associated with the athletes’ in-game performance, the authors collected National Football League players’ social media activities throughout one season, in addition to player performance and profile information. To account for the multilevel and panel structure of the data, they conducted a series of fixed-effects panel models. In addition to a negative relationship between social media posting frequency and performance, the authors found that players who post social media content with a higher level of humility are more likely to have better performances. However, this humility–performance association follows an inverted U-shaped relationship. The results provide insight into how critical athletes’ social media activity is for in-game performance. This study also provides important implications for athletes, team coaches, staff, and managers and provides guidance for future research.
Andrew M. Colombo-Dougovito and Jihyun Lee
Researchers posit that physical activity (PA) settings may provide an increased opportunity for social interaction. However, little consensus exists regarding the construct of social skills. Moreover, little is known about what type or amount of PA is necessary for individuals on the autism spectrum to benefit from this increased interaction. Thus, this scoping review synthesized the components (e.g., design, participants, independent and dependent variables, etc.) and findings of PA-based interventions that included social skill components to identify how interventions have incorporated these skills in different settings. Based on a review of 25 articles, this review revealed a great deal of variability in the types of PA, social skills, and instruments studied, as well as the intensity of intervention delivery in the published findings. No longitudinal studies were identified as a part of the search. These results provide a foundation for the design of effective PA-based interventions that may have an increased impact on the social skills of individuals on the autism spectrum. Future research should employ longitudinal designs to capture the relationship between social skills and PA, as well as to increase the likelihood of capturing change.