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Mohamed Romdhani, Nizar Souissi, Imen Moussa-Chamari, Yassine Chaabouni, Kacem Mahdouani, Zouheir Sahnoun, Tarak Driss, Karim Chamari, and Omar Hammouda

Purpose: To compare the effect of a 20-minute nap opportunity (N20), a moderate dose of caffeine (CAF; 5 mg·kg−1), or a moderate dose of caffeine before N20 (CAF+N) as possible countermeasures to the decreased performance and the partial sleep deprivation–induced muscle damage. Methods: Nine male, highly trained judokas were randomly assigned to either baseline normal sleep night, placebo, N20, CAF, or CAF+N. Test sessions included the running-based anaerobic sprint test, from which the maximum (P max), mean (P mean), and minimum (P min) powers were calculated. Biomarkers of muscle, hepatic, and cardiac damage and of enzymatic and nonenzymatic antioxidants were measured at rest and after the exercise. Results: N20 increased P max compared with placebo (P < .01, d = 0.75). CAF+N increased P max (P < .001, d = 1.5; d = 0.94), P min (P < .001, d = 2.79; d = 2.6), and P mean (P < .001, d = 1.93; d = 1.79) compared with placebo and CAF, respectively. Postexercise creatine kinase increased whenever caffeine was added, that is, after CAF (P < .001, d = 1.19) and CAF+N (P < .001, d = 1.36). Postexercise uric acid increased whenever participants napped, that is, after N20 (P < .001, d = 2.19) and CAF+N (P < .001, d = 2.50) and decreased after CAF (P < .001, d = 2.96). Conclusion: Napping improved repeated-sprint performance and antioxidant defense after partial sleep deprivation. Contrarily, caffeine increased muscle damage without improving performance. For sleep-deprived athletes, caffeine before a short nap opportunity would be more beneficial for repeated sprint performance than each treatment alone.

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Ryan Snelgrove and Laura Wood

This article describes the design of an undergraduate course in which students learn how to cocreate change using social entrepreneurship. This approach is presented as a way of broadening sport management students’ awareness of nontraditional career opportunities and facilitating an understanding of the skills and knowledge necessary to succeed as a social entrepreneur. Drawing on situational learning theory and cognitive learning theory, the course facilitates learning through student engagement in a community of practice and weekly workshops.

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Sara Birch, Torben Bæk Hansen, Maiken Stilling, and Inger Mechlenburg

Background: Pain catastrophizing is associated with pain both before and after a total knee arthroplasty (TKA). However, it remains uncertain whether pain catastrophizing affects physical activity (PA). The aim was to examine the influence of pain catastrophizing on the PA profile, knee function, and muscle mass before and after a TKA. Methods: The authors included 58 patients with knee osteoarthritis scheduled for TKA. Twenty-nine patients had a score >22 on the Pain Catastrophizing Scale (PCS), and 29 patients had a score <11. PA was measured with a triaxial accelerometer preoperative, 3 months, and 12 months after TKA. Other outcome measures consisted of the Knee Osteoarthritis Outcome Score and dual-energy X-ray absorptiometry scans. Results: The authors found no difference in PA between patients with a better/low or a worse/high score on the PCS, and none of the groups increased their mean number of steps/day from preoperative to 12 months postoperative. Patients with better/low PCS scores had higher/better preoperative scores on the Knee Osteoarthritis Outcome Score subscales (symptoms, pain, and activity of daily living), and they walked longer in the 6-min walk test. Further, they had lower body mass index, lower percent fat mass, and higher percent muscle mass than patients with worse/high PCS scores both before and after a TKA. Conclusion: Preoperative pain catastrophizing did not influence PA before or after a TKA. Although the patients improved substantially in self-reported knee function, their PA did not increase. This may be important to consider when the clinicians are informing the patients about the expected benefits from the operation.

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Natalie M. Welch, Jessica L. Siegele, and Robin Hardin

Women continue to struggle to reach senior-level leadership positions in collegiate sports, and ethnic minorities face the challenges due to their ethnicity as well. This research examined the experiences and challenges of ethnic minority women who are collegiate athletic directors at predominantly White institutions (PWIs). Semistructured interviews were conducted with eight participants using intersectionality as a theoretical framework. Three themes emerged from the data analysis: (a) intersectional challenges, (b) questions of competence, and (c) professional support. The women were continually battling the idea of having to prove themselves and negotiating the challenges of being an ethnic minority woman working in collegiate athletics. They credit their professional networks as a valuable resource during their career progression. The women noted that sexism was more prevalent in their experiences than issues related to their ethnicity. The masculine athletic director stereotype persists in collegiate sports, but the findings of this study can contest the notion of a standard leadership identity that has long been perceived as a White man.

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Raki Kawama, Masamichi Okudaira, David H. Fukuda, Hirohiko Maemura, and Satoru Tanigawa

Context: Each hamstring muscle is subdivided into several regions by multiple motor nerve branches, which implies each region has different muscle activation properties. However, little is known about the muscle activation of each region with a change in the knee joint angle. Understanding of regional activation of the hamstrings could be helpful for designing rehabilitation and training programs targeted at strengthening a specific region. Objective: To investigate the effect of knee joint angle on the activity level of several regions within the individual hamstring muscles during isometric knee-flexion exercise with maximal effort (MVCKF). Design: Within-subjects repeated measures. Setting: University laboratory. Participants: Sixteen young males with previous participation in sports competition and resistance training experience. Intervention: The participants performed 2 MVCKF trials at each knee joint angle of 30°, 60°, and 90°. Outcome Measures: Surface electromyography was used to measure muscle activity in the proximal, middle, and distal regions of the biceps femoris long head (BFlh), semitendinosus, and semimembranosus of hamstrings at 30°, 60°, and 90° of knee flexion during MVCKF. Results: Muscle activity levels in the proximal and middle regions of the BFlh were higher at 30° and 60° of knee flexion than at 90° during MVCKF (all: P < .05). Meanwhile, the activity levels in the distal region of the BFlh were not different among all of the evaluated knee joint angles. In semitendinosus and semimembranosus, the activity levels were higher at 30° and 60° than at 90°, regardless of region (all: P < .05). Conclusion: These findings suggest that the effect of knee joint angle on muscle activity level differs between regions of the BFlh, whereas that is similar among regions of semitendinosus and semimembranosus during MVCKF.

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Isabel B. Rodrigues, Matteo Ponzano, Debra A. Butt, Joan Bartley, Zahra Bardai, Maureen C. Ashe, Philip D. Chilibeck, Lehana Thabane, John D. Wark, Jackie Stapleton, and Lora M. Giangregorio

Walking is a common activity among older adults. However, the effects of walking on health-related outcomes in people with low bone mineral density (BMD) are unknown. The authors included randomized controlled trials comparing walking to control in individuals aged ≥50 years with low BMD and at risk of fractures. The authors identified 13 randomized controlled trials: nine multicomponent interventions including walking, one that was walking only, and three Nordic walking trials. Most studies had a high risk of bias. Nordic walking may improve the Timed Up-and-Go values (1.39 s, 95% CI [1.00, 1.78], very low certainty). Multicomponent interventions including walking improved the 6-min walk test (39.37 m, 95% CI [21.83, 56.91], very low certainty) and lumbar spine BMD (0.01 g/cm2, 95% CI [0.00, 0.03], low certainty evidence). The effects on quality of life or femoral neck BMD were not significant. There were insufficient data on fractures, falls, or mortality. Nordic walking may improve physical functioning. The effects on other outcomes are less certain; one may need to combine walking with other exercises to be of benefit.

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Diana M. Doumas and Nadine R. Mastroleo

High school athletes are at risk for heavy alcohol use, which is associated with consequences that may negatively impact performance and eligibility to participate in sports. This study evaluated the efficacy of a web-based personalized normative feedback intervention on reducing alcohol use among high school athletes in their senior year. Class periods were randomized to the intervention or an assessment-only control group. Athletes completed surveys at baseline and at a 6-week follow-up. They were classified as high-risk or low-risk drinkers based on baseline reports of binge drinking. Results indicated that for athletes classified as high-risk drinkers, those in the intervention group reported significantly greater reductions in quantity of weekly drinking and peak drinking quantity compared with those in the assessment-only control group. There were no significant intervention effects for frequency of alcohol use. Findings support the efficacy of web-based personalized normative feedback intervention for reducing alcohol use among high school senior athletes.

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Louis Howe, Jamie S. North, Mark Waldron, and Theodoros M. Bampouras

Context: Ankle dorsiflexion range of motion (DF ROM) has been associated with a number of kinematic and kinetic variables associated with landing performance that increase injury risk. However, whether exercise-induced fatigue exacerbates compensatory strategies has not yet been established. Objectives: (1) Explore differences in landing performance between individuals with restricted and normal ankle DF ROM and (2) identify the effect of fatigue on compensations in landing strategies for individuals with restricted and normal ankle DF ROM. Design: Cross-sectional. Setting: University research laboratory. Patients or Other Participants: Twelve recreational athletes with restricted ankle DF ROM (restricted group) and 12 recreational athletes with normal ankle DF ROM (normal group). Main Outcome Measure(s): The participants performed 5 bilateral drop-landings, before and following a fatiguing protocol. Normalized peak vertical ground reaction force, time to peak vertical ground reaction force, and loading rate were calculated, alongside sagittal plane initial contact angles, peak angles, and joint displacement for the ankle, knee, and hip. Frontal plane projection angles were also calculated. Results: At the baseline, the restricted group landed with significantly less knee flexion (P = .005, effect size [ES] = 1.27) at initial contact and reduced peak ankle dorsiflexion (P < .001, ES = 1.67), knee flexion (P < .001, ES = 2.18), and hip-flexion (P = .033, ES = 0.93) angles. Sagittal plane joint displacement was also significantly less for the restricted group for the ankle (P < .001, ES = 1.78), knee (P < .001, ES = 1.78), and hip (P = .028, ES = 0.96) joints. Conclusions: These findings suggest that individuals with restricted ankle DF ROM should adopt different landing strategies than those with normal ankle DF ROM. This is exacerbated when fatigued, although the functional consequences of fatigue on landing mechanics in individuals with ankle DF ROM restriction are unclear.

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Naroa Etxebarria, Jackson Wright, Hamish Jeacocke, Cristian Mesquida, and David B. Pyne

Negative or evenly paced racing strategies often lead to more favorable performance outcomes for endurance athletes. However, casual inspection of race split times and observational studies both indicate that elite triathletes competing in Olympic-distance triathlon typically implement a positive pacing strategy during the last of the 3 disciplines, the 10-km run. To address this apparent contradiction, the authors examined data from 14 International Triathlon Union elite races over 3 consecutive years involving a total of 725 male athletes. Analyses of race results confirm that triathletes typically implement a positive running pace strategy, running the first lap of the standard 4-lap circuit substantially faster than laps 2 (∼7%), 3 (∼9%), and 4 (∼12%). Interestingly, mean running pace in lap 1 had a substantially lower correlation with 10-km run time (r = .82) than both laps 2 and 3. Overall triathlon race performance (ranking) was best associated with run performance (r = .82) compared with the swim and cycle sections. Lower variability in race pace during the 10-km run was also reflective of more successful run times. Given that overall race outcome is mainly explained by the 10-km run performance, with top run performances associated with a more evenly paced strategy, triathletes (and their coaches) should reevaluate their pacing strategy during the run section.

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Kate M. Luckin-Baldwin, Claire E. Badenhorst, Ashley J. Cripps, Grant J. Landers, Robert J. Merrells, Max K. Bulsara, and Gerard F. Hoyne

Purpose: The completion of concurrent strength and endurance training can improve exercise economy in cyclists and runners; however, the efficacy of strength training (ST) implementation to improve economy in long-distance (LD) triathletes has not yet been investigated. The purpose of this study was to investigate physiological outcomes in LD triathletes when ST was completed concurrently to endurance training. Methods: A total of 25 LD triathletes were randomly assigned to either 26 weeks of concurrent endurance and ST (n = 14) or endurance training only (n = 11). The ST program progressed from moderate (8–12 repetitions, ≤75% of 1-repetition maximum, weeks 0–12) to heavy loads (1–6 repetitions, ≥85% of 1-repetition maximum, weeks 14–26). Physiological and performance indicators (cycling and running economy, swim time, blood lactate, and heart rate) were measured during a simulated triathlon (1500-m swim, 60-min cycle, and 20-min run) at weeks 0, 14, and 26. Maximal strength and anthropometric measures (skinfolds and body mass) were also collected at these points. Results: The endurance strength group significantly improved maximal strength measures at weeks 14 and 26 (P < .05), cycling economy from weeks 0 to 14 (P < .05), and running economy from weeks 14 to 26 (P < .05) with no change in body mass (P > .05). The endurance-only group did not significantly improve any economy measures. Conclusions: The addition of progressive load ST to LD triathletes’ training programs can significantly improve running and cycling economy without an increase in body mass.