Purpose: To present the acclimatization strategy employed by an elite athlete prior to 2 successful ascents to Mount Everest (including a “fastest known time”) in 1 wk. Methods: Training volume, training content, and altitude exposure were recorded daily. Vertical velocity was recorded by GPS (global positioning system) heart-rate monitor. Results: The subject first used a live high–train low and high preacclimatization method in normobaric hypoxia (NH). Daily, he combined sleeping in a hypoxic tent (total hours: ∼260) and exercising “as usual” in normoxia but also in NH (altitude >6000 m: 30 h), including at high intensity. The hypoxic sessions were performed at the second threshold on treadmill in NH at 6000 m, and the pulse saturation increased from 70% to 85% over 1 mo. Then, the subject was progressively exposed to hypobaric hypoxia, first in the Alps and then in the Himalayas. On day 18, he reached for the second time an altitude >8000 m with the fastest vertical velocity (350 m/h) ever measured between 6300 and 8400 m. Afterward, he climbed twice in a week to the summit of Mount Everest (8848 m, including a “fastest known time” of 26.5 h from Rongbuk Monastery, 5100 m). Conclusion: Overall, this acclimatization was successful and in line with the most recent recommendations: first, using live high–train low and high, and second, using hypobaric hypoxia at increasing altitudes for a better translation of the NH benefits to hypobaric hypoxia. This case study reports the preparation for the most outstanding performance ever acheived at an extreme altitude.
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Grégoire P. Millet and Kilian Jornet
Stephen S. Cheung
Katie Teller, Mark Abbey-Lambertz, Nasira Sharma, Alan Waite, Scott Ickes and Jason A. Mendoza
Background: The walking school bus (WSB) is a promising intervention to increase walking to school and physical activity in school-age children. The aim of this qualitative study was to assess parent perceptions of a WSB program that was part of a randomized controlled trial to inform future programs. Methods: The authors interviewed 45 parents whose children had participated in a WSB program in the Seattle area, in which third- and fifth-grade students walked to/from school with adult chaperones along a set route. The authors performed a qualitative analysis of the interview transcripts and coded interview segments into 4 broad categories as follows: facilitators, barriers, general positive sentiments, and proposals. Results: Most parents spoke of the benefits of the WSB program; in particular, parents frequently applauded exercise/physical health benefits. Of the barriers, the most frequently cited was time, with work schedule and commute changes leading some families to walk less frequently. Conclusions: Most parents voiced support for the WSB program as a means to improve child health, to learn pedestrian safety, and to interact with positive adult role models. Parents made several suggestions to improve the program, including better recruitment methods, logistical improvements, and a platform for communicating with other parents.
Paul A. Solberg, Will G. Hopkins, Gøran Paulsen and Thomas A. Haugen
Purpose: To quantify age of peak performance and performance improvements in the years preceding peak age in elite weightlifting and powerlifting athletes using results from powerlifting World Championships in 2003–2017 and weightlifting World Championships and Olympic Games in 1998–2017. Methods: Individual performance trends were derived by fitting a quadratic curve separately to each athlete’s performance and age data. Effects were evaluated using magnitude-based inferences. Results: Peak age (mean [SD]) was 35 (7) y for powerlifters and 26 (3) y for weightlifters, a large most likely substantial difference of 9, ±1 y (mean, 90% confidence limit). Men showed possibly higher peak age than women in weightlifting (0.8, ±0.7 y; small) and a possibly lower peak age in powerlifting (1.3, ±1.8 y; trivial). Peak age of athletes who ever won a medal was very likely less than that of nonmedalists in weightlifting (1.3, ±0.6 y; small), while the difference in powerlifters was trivial but unclear. Five-year improvements prior to peak age were 12% (10%) for powerlifters and 9% (7%) for weightlifters, a small possibly substantial difference (2.9, ±2.1%). Women exhibited possibly greater improvements than men in powerlifting (2.7, ±3.8%; small) and very likely greater in weightlifting (3.5, ±1.6%; small). Medalists possibly improved less than nonmedalists among powerlifters (−1.7, ±2.3%; small), while the difference was likely trivial for weightlifters (2.3, ±1.8%). Conclusion: These novel insights on performance development will be useful for practitioners evaluating strategies for achieving success.
Bhanu Sharma and Brian W. Timmons
The multidisciplinary field of pediatric traumatic brain injury (TBI) and exercise medicine is of growing importance. There is active study into the diagnostic and therapeutic potential of exercise in pediatric TBI as well as the effects of TBI on postinjury fitness. With the evidence-based growing, a literature review can help establish the state of the science and inform future research. Therefore, the authors performed a narrative review (based on a search of 6 health sciences databases) to summarize evidence on pediatric TBI and cardiorespiratory fitness, muscular fitness and neuromotor control, and obesity. To date, studies related to cardiorespiratory fitness have centered on exercise tolerance and readiness to return to play, and indicate that protracted rest may not facilitate symptom recovery; this suggests a role for exercise in concussion management. Furthermore, strength and gait may be impaired following pediatric brain injury, and interventions designed to train these impairments may lead to their improvement. Pediatric brain injury can also lead to changes in body composition (which may be related to poorer cognitive recovery), but additional research is required to better understand such associations. This narrative review of pediatric TBI and exercise medicine can serve as a reference for researchers and clinicians alike.
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.
Alejandro Pérez-Castilla, Antonio Piepoli, Gabriel Garrido-Blanca, Gabriel Delgado-García, Carlos Balsalobre-Fernández and Amador García-Ramos
Objective: To compare the accuracy of different devices to predict the bench-press 1-repetition maximum (1RM) from the individual load–velocity relationship modeled through the multiple- and 2-point methods. Methods: Eleven men performed an incremental test on a Smith machine against 5 loads (45–55–65–75–85%1RM), followed by 1RM attempts. The mean velocity was simultaneously measured by 1 linear velocity transducer (T-Force), 2 linear position transducers (Chronojump and Speed4Lift), 1 camera-based optoelectronic system (Velowin), 2 inertial measurement units (PUSH Band and Beast Sensor), and 1 smartphone application (My Lift). The velocity recorded at the 5 loads (45–55–65–75–85%1RM), or only at the 2 most distant loads (45–85%1RM), was considered for the multiple- and 2-point methods, respectively. Results: An acceptable and comparable accuracy in the estimation of the 1RM was observed for the T-Force, Chronojump, Speed4Lift, Velowin, and My Lift when using both the multiple- and 2-point methods (effect size ≤ 0.40; Pearson correlation coefficient [r] ≥ .94; standard error of the estimate [SEE] ≤ 4.46 kg), whereas the accuracy of the PUSH (effect size = 0.70–0.83; r = .93–.94; SEE = 4.45–4.80 kg), and especially the Beast Sensor (effect size = 0.36–0.84; r = .50–.68; SEE = 9.44–11.2 kg), was lower. Conclusions: These results highlight that the accuracy of 1RM prediction methods based on movement velocity is device dependent, with the inertial measurement units providing the least accurate estimate of the 1RM.
Álvaro Cuñado-González, Aitor Martín-Pintado-Zugasti and Ángel L. Rodríguez-Fernández
Context: Prevalence studies have been carried out widely on elite volleyball players. However, the extent to which specific prevention strategies are used and the influence of the sport equipment on the occurrence of injuries have been sparsely investigated. Objective: To describe the prevalence of injuries sustained during 1 season in elite Spanish volleyball leagues and to investigate the association of injuries with factors such as player court position, injury mechanism, type of shoes used when playing, or participation in prevention activities. Design: Descriptive cross-sectional epidemiology study: observational study. Setting: European elite professional volleyball. Participants: Professional volleyball players from the elite Spanish volleyball league. Main Outcome Measures: A self-report questionnaire assessed the presence of injury during a volleyball season. Questions included the type of injury, its anatomic location, participation in prevention strategies, shoe type, the injury mechanism, the season period, the period of leave, and the treatment received. Results: In total, 490 players (71.2% response rate) completed and returned the questionnaire. The injury prevalence was 66.9%, and the average of injuries per player was 0.94 (0.85) (range: 0–4). Most Spanish elite volleyball players participated in prevention programs during the season (90.3%) and played volleyball with low-top shoes (83.6%), but these factors were not associated with the prevalence of injuries (P > .05). The anatomic regions with the most injuries were the ankle, knee, and shoulder; the most common types of injury were sprains, tendinopathies, and strains, usually occurring during blocking and attack actions during the in-season period. Conclusions: Despite most elite volleyball players participating in prevention programs, the results reveal a high injury prevalence. Further prospective research on the effectiveness of prevention strategies in elite volleyball is needed.
Jens De Rycke, Veerle De Bosscher, Hiroaki Funahashi and Popi Sotiriadou
Many Nations are increasingly investing public money in elite sport on the belief that this will trigger a range of benefits for the population. However, there is lack of insight into how the population perceives elite sport’s impact on society. This study developed and tested a measurement scale assessing the publics’ beliefs of the positive and negative societal impacts that could potentially flow from elite sport. A sample of the Belgian population (N = 1,102) was surveyed. A 32-item scale was built using principal component and confirmatory factor analysis procedures for which the goodness-of-fit indices were excellent. Multivariate analysis revealed that the Belgian population perceived elite sport to have mostly positive societal impacts. The study findings can serve researchers wanting to measure the perceived potential positive and negative societal impacts of elite sport.
Jonathan M. Williams, Michael Gara and Carol Clark
Context: Balance is important for injury prediction, prevention, and rehabilitation. Clinical measurement of higher level balance function such as hop landing is necessary. Currently, no method exists to quantify balance performance following hopping in the clinic. Objective: To quantify the sacral acceleration profile and test–retest reliability during hop landing. Participants: A total of 17 university undergraduates (age 27.6 [5.7] y, height 1.73 [0.11] m, weight 74.1 [13.9] kg). Main Outcome Measure: A trunk-mounted accelerometer captured the acceleration profile following landing from hopping forward, medially, and laterally. The path length of the acceleration traces were computed to quantify balance following landing. Results: Moderate to excellent reliability (intraclass correlation coefficient .67–.93) for hop landing was established with low to moderate SEM (4%–16%) and minimal detectable change values (13%–44%) for each of the hop directions. Significant differences were determined in balance following hop landing from the different directions. Conclusion: The results suggest that hop landing balance can be quantified by trunk-mounted accelerometry.