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Titouan P. Perrin, Jeremy Rossi, Hugo A. Kerhervé, and Guillaume Y. Millet

Purpose: Carbon plates have been used to increase running shoes’ longitudinal bending stiffness (LBS), leading to reductions in the energy cost of level running (Cr). However, whether or not this is true during uphill (UH) running remains unknown. The aim of our study was to identify the effect of LBS on Cr during UH running. Methods: Twenty well-trained male runners participated in this study. Cr was determined using gas exchange during nine 4-minute bouts performed using 3 different LBS shoe conditions at 2.22 and 4.44 m/s on level and 2.22 m/s UH (gradient: + 15%) running. All variables were compared using 2-way analyses of variance (LBS × speed/grade effects). Results: There was no significant effect of LBS (F = 2.04; P = .14, η p 2 = .11 ) and no significant LBS × grade interaction (F = 0.31; P = .87, η p 2 = .02 ). Results were characterized by a very large interindividual variability in response to LBS changes. Conclusions: The current study contributes to a growing body of literature reporting no effect of LBS on Cr during level and UH running. Yet, the very large interindividual differences in response to changes in LBS suggest that increasing shoe LBS may be beneficial for some runners.

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Edward M. Balog, Mateo Golloshi, HyunGyu Suh, and Melinda Millard-Stafford

Deuterium oxide (D2O) appearance in blood is a marker of fluid bioavailability. However, whether biomarker robustness (e.g., relative fluid delivery speed) is consistent across analytical methods (e.g., cavity ring-down spectroscopy) remains unclear. Fourteen men ingested fluid (6 ml/kg body mass) containing 0.15 g/kg D2O followed by 45 min blood sampling. Plasma (D2O) was detected (n = 8) by the following: isotope-ratio mass spectrometry after vapor equilibration (IRMS-equilibrated water) or distillation (IRMS-plasma) and cavity ring-down spectroscopy. Two models calculated D2O halftime to peak (t 1/2max): sigmoid curve fit versus asymmetric triangle (TRI). Background (D2O) differed (p < .001, η2 = .98) among IRMS-equilibrated water, IRMS-plasma, and cavity ring-down spectroscopy (152.2 ± 0.8, 147.2 ± 1.5, and 137.7 ± 2.2 ppm), but did not influence (p > .05) D2O appearance (Δppm), time to peak, or t 1/2max. Stratifying participants based on mean t 1/2max (12 min) into “slow” versus “fast” subgroups resulted in a 5.8 min difference (p < .001, η2 = .73). Significant t 1/2max model (p = .01, η2 = .44) and Model × Speed Subgroup interaction (p = .005, η2 = .50) effects were observed. Bias between TRI and sigmoid curve fit increased with t 1/2max speed: no difference (p = .75) for fast (9.0 min vs. 9.2 min, respectively) but greater t 1/2max (p = .001) with TRI for the slow subgroup (16.1 min vs. 13.7 min). Fluid bioavailability markers are less influenced by which laboratory method is used to measure D2O as compared with the individual variability effects that influence models for calculating t 1/2max. Thus, TRI model may not be appropriate for individuals with slow fluid delivery speeds.

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Eun-Young Lee, Lee Airton, Heejun Lim, and Eun Jung

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Lindsay Nettlefold, Samantha M. Gray, Joanie Sims-Gould, and Heather A. McKay

Interventions that are effective in research (efficacy or effectiveness) trials cannot improve health at a population level unless they are successfully delivered more broadly (scaled up) outside of the research setting. However, scale-up is often relegated to the too hard basket. Factors such as the need to adapt interventions prior to implementing them in diverse settings at scale, retaining fidelity to the intervention, and cultivating the necessary community and funding partnerships can all present a challenge. In the present review article, we present a scale-up case study—Choose to Move—an effective health-promoting intervention for older adults. The objectives of this review were to (a) describe the frameworks and processes adopted to implement, adapt, and scale up Choose to Move across British Columbia, Canada; (b) provide an overview of the phased approach to scale-up; and (c) share key lessons learned while implementing and scaling up health-promoting interventions with community partners across more than 2 decades.

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Michelle D. Guerrero, Sarah Moore, Guy Faulkner, Karen C. Roberts, Raktim Mitra, Leigh M. Vanderloo, Ryan E. Rhodes, and Mark S. Tremblay

Purpose: The purposes of the current study were to identify risk profiles for nonadherence among children and youth (5–17 y) at the 6-month mark of the COVID-19 pandemic and to discuss similarities and differences between risk profiles identified in the current study and those identified at the 1-month mark of the pandemic. Methods: Data were part of a nationally representative sample of 1143 parents (M age = 43.07 y, SD = 8.16) of children and youth (5–17 y) living in Canada. Survey data were collected in October 2020. Results: Results showed that 3.8% met all movement behavior recommendations, 16.2% met the physical activity recommendation, 27% met the screen time recommendation, and 63.8% met the sleep recommendation. Characteristics associated with nonadherence to all movement behaviors included low parental perceived capability to restrict screen time and decreased overall time spent outdoors. Characteristics associated with nonadherence to the physical activity and screen time recommendations included youth (12–17 y), low parental perceived capability to restrict screen time, decreased time spent outdoors, and increased screen time. Conclusion: Results emphasized the importance of parental perceived capability to restrict screen time and children’s and youth’s outdoor time and showed that pandemic-related factors have impacted children and youth differently.

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Alberto Grao-Cruces, Alejandro Pérez-Bey, José Jiménez-Iglesias, Carolina Cruz-León, Verónica Cabanas-Sánchez, Oscar L. Veiga, and José Castro-Piñero

Background: The aim of this study was to examine associations of total volume and bouts of sedentary time (ST) and moderate to vigorous physical activity (MVPA) with physical fitness (PF) in youth. Methods: This was a 2-year follow-up study with 1418 children and adolescents (51.7% boys). Accelerometers were used to assess ST and MVPA. Cardiorespiratory and muscular fitness values were objectively measured and combined in a global PF variable. Weight status was objectively obtained. Linear regression analyses were used to examine the cross-sectional (using scores at baseline) and longitudinal associations (using the change in the variables) of total volume and bouts of ST and MVPA with PF. Results: Total ST was negatively associated with global PF (β = −0.488, P < .001 in cross-sectional analysis; β = −0.234, P = .003 in longitudinal analysis). However, this association was not independent of MVPA. Total volume of MVPA showed a positive association with global PF independently of ST and weight status (β = 0.285, P < .001 in cross-sectional analysis; β = 0.119, P = .001 in longitudinal analysis). Longitudinal associations found between ST and MVPA accumulated in bouts of various lengths and global PF became nonsignificant when their respective total volumes are included in the model. Conclusions: These results underline the need to accumulate minutes of MVPA, regardless of the bout duration, to increase PF levels in youth.

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I-Min Lee, Christopher C. Moore, and Kelly R. Evenson

There is much evidence showing that physical activity is related to optimal health, including physical and mental function, and quality of life. Additionally, data are accumulating with regard to the detrimental health impacts of sedentary behavior. Much of the evidence related to long-term health outcomes, such as cardiovascular disease and cancer—the two leading causes of death in the United States and worldwide—comes from observational epidemiologic studies and, in particular, prospective cohort studies. Few data on these outcomes are derived from randomized controlled trials, conventionally regarded as the “gold standard” of research designs. Why is there a paucity of data from randomized trials on physical activity or sedentary behavior and long-term health outcomes? A further issue to consider is that prospective cohort studies investigating these outcomes can take a long time to accrue sufficient numbers of endpoints for robust and meaningful findings. This contrasts with the rapid pace at which technology advances. Thus, while the use of devices for measuring physical behaviors has been an important development in large-scale epidemiologic studies over the past decade, cohorts that are now publishing results on health outcomes related to accelerometer-assessed physical activity and sedentary behavior may have been initiated years ago, using “dated” technology. This paper, based on a keynote presentation at 8th International Conference on Ambulatory Monitoring of Physical Activity and Movement 2022, discusses the issues of study design and slow pace of discovery in prospective cohort studies and suggests some possible ways to maximize the utility and comparability of “dated” device data from prospective cohort studies for research investigations using the Women’s Health Study as an example.

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Claudio Quagliarotti, Matteo Cortesi, Vittorio Coloretti, Silvia Fantozzi, Giorgio Gatta, Marco Bonifazi, Paola Zamparo, and Maria Francesca Piacentini

Purpose: Wetsuits have been shown to change swim biomechanics and, thus, increase performance, but not all athletes are comfortable with their use because of possible modifications in motor coordination. The aim of this study was to evaluate the effects of wetsuit use on biomechanical, physiological, and perceptual variables. Methods: Eleven national- and international-level triathletes, familiar with wetsuit use, performed 7 × 200-m front crawl at constant preset speed twice, with and without a full wetsuit. The trunk incline (TI) and index of coordination (IdC) were measured stroke by stroke using video analysis. Stroke, breaths, and kick count, and timing (as breathing/kick action per arm-stroke cycle); stroke length (SL); and underwater length were analyzed using inertial-measurement-unit sensors. Heart rate (HR), rating of perceived exertion (RPE), and swimming comfort were monitored during the task. Results: A lower TI; IdC; number of strokes, kicks, and breaths; HR; and RPE for each 200 m were found in wetsuit compared with swimsuit condition. Higher values of SL and underwater length were found in wetsuit, whereas no differences were found in swimming comfort and timing of kicks and breaths. An increase for swimsuit condition in number of strokes and breaths, HR, and RPE was found during the task compared with the first 200 m. Conclusion: Wetsuit use reduces TI and, thus, drag; increases propelling proficiency; and shows lower fatigability, without modifying motor coordination, compared with swimsuit use at the same speed. The use of a wetsuit during training sessions is recommended to increase comfort and the positive effects on performance.

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Dustin P. Joubert, Trace A. Dominy, and Geoffrey T. Burns

Purpose: The Nike Vaporfly line of running shoes improves running economy by ∼2.7% to 4.2% at running speeds of 13 to 18 km·h−1. It is unclear whether similar benefits are conferred at slower speeds. Our purpose was to determine the effects of the Nike ZoomX Vaporfly Next% 2 (VFN2) on running economy at 10 and 12 km·h−1 compared with a mass-matched control (CTRL) shoe. Methods: Sixteen runners completed 4 × 5-minute trials at both 10 and 12 km·h−1 on the same day. Each shoe was tested twice at each speed in a counterbalanced, mirrored sequence. Data are displayed as mean (SD). Results: A 2-way repeated-measures analysis of variance showed a significant shoe × speed interaction for oxygen consumption (P = .021). At 12 km·h−1, oxygen consumption (in mL·kg−1·min−1) was lower (−1.4% [1.1%]; P < .001) for VFN2 (35.8 [1.7]) relative to CTRL (36.4 [1.7]). That was greater in magnitude than the differences observed at 10 km·h−1 (−0.9% [1.8%]; P = .065) between VFN2 (29.4 [1.9]) and CTRL (29.6 [1.9]). Conclusions: From these data, it appears that the VFN2 still enhances running economy at 10 and 12 km·h−1; however, these benefits are smaller in magnitude compared with previous research at faster speeds.

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Michael J. Marsala, Shannon Belfry, Joseph B. Orange, and Anita D. Christie

Sex-related differences in changes in functional fitness over time were longitudinally assessed in older adults participating in a group-based multimodal exercise program. From a database, functional fitness scores were obtained for 89 older adults (71.6 ± 6.5 years old) who had completed two assessments, 5–8 years apart. Lower body strength, upper body strength, aerobic endurance, flexibility, and change of direction performances were compared over time and with normative values. Females (p = .02), but not males, had an improvement in upper body strength over time. Females were also more flexible than males at both assessments (p ≤ .02). Of those who had five consecutive assessments, females were more flexible than males (p ≤ .05) and had a faster change of direction ability (p < .001). When compared with normative values, our results indicate that typical time-related functional fitness loss can be attenuated with group exercise. Our results further support the need to tailor exercise prescription according to the individual.