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Elin Ekblom-Bak, Örjan Ekblom, Gunnar Andersson, Peter Wallin and Björn Ekblom

Background: The importance of youth physical activity (PA) for adulthood PA, performance, and health was retrospectively evaluated. Methods: A total of 258,146 participants (49% women), aged 19–70, with a first-time health-profile assessment between 1982 and 2015, provided self-reported data on current perceived health, PA, lifestyle, and physical education class participation, and PA outside school hours before age 20. Data on anthropometrics, blood pressure, and estimated maximal oxygen consumption (VO2max) were obtained. Results: Women participating in physical education class, compared with those who did not, had significantly lower OR (range: 0.81–0.87) for perceiving poor overall health, general obesity, and high diastolic blood pressure after adjustment for potential confounders, and increased OR (range: 1.17–1.23) for exercising regularly and a normal/high VO2max in adulthood. For men, the ORs were significantly lower (range: 0.66–0.86) for poor perceived overall health, general, and abdominal obesity. These associations were seen for participants up to 70 years. Increased PA outside school hours revealed even stronger beneficial associations. In joint analyses, both youth and current PA were important for lower OR of poor health and being obese in adulthood. Conclusions: Physical education class participation and additional PA after school hours were both important for perceived health, PA, VO2max, and metabolic health in adulthood up to 70 years.

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Louise M. Burke, John A. Hawley, Asker Jeukendrup, James P. Morton, Trent Stellingwerff and Ronald J. Maughan

From the breakthrough studies of dietary carbohydrate and exercise capacity in the 1960s through to the more recent studies of cellular signaling and the adaptive response to exercise in muscle, it has become apparent that manipulations of dietary fat and carbohydrate within training phases, or in the immediate preparation for competition, can profoundly alter the availability and utilization of these major fuels and, subsequently, the performance of endurance sport (events >30 min up to ∼24 hr). A variety of terms have emerged to describe new or nuanced versions of such exercise–diet strategies (e.g., train low, train high, low-carbohydrate high-fat diet, periodized carbohydrate diet). However, the nonuniform meanings of these terms have caused confusion and miscommunication, both in the popular press and among the scientific community. Sports scientists will continue to hold different views on optimal protocols of fuel support for training and competition in different endurance events. However, to promote collaboration and shared discussions, a commonly accepted and consistent terminology will help to strengthen hypotheses and experimental/experiential data around various strategies. We propose a series of definitions and explanations as a starting point for a more unified dialogue around acute and chronic manipulations of fat and carbohydrate in the athlete’s diet, noting philosophies of approaches rather than a single/definitive macronutrient prescription. We also summarize some of the key questions that need to be tackled to help produce greater insight into this exciting area of sports nutrition research and practice.

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Janet E. Fulton, David M. Buchner, Susan A. Carlson, Deborah Borbely, Kenneth M. Rose, Ann E. O’Connor, Janelle P. Gunn and Ruth Petersen

Physical activity can reduce the risk of at least 20 chronic diseases and conditions and provide effective treatment for many of these conditions. Yet, physical activity levels of Americans remain low, with only small improvements over 20 years. The Centers for Disease Control and Prevention (CDC) considered what would accelerate progress and, as a result, developed Active People, Healthy NationSM, an aspirational initiative to improve physical activity in 2.5 million high school youth and 25 million adults, doubling the 10-year improvement targets of Healthy People 2020. Active People, Healthy NationSM will implement evidence-based guidance to improve physical activity through 5 action steps centered on core public health functions: (1) program delivery, (2) partnership mobilization, (3) effective communication, (4) cross-sectoral training, and (5) continuous monitoring and evaluation. To achieve wide-scale impact, Active People, Healthy NationSM will need broad engagement from a variety of sectors working together to coordinate activities and initiatives.

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Susan Carter

Barbara Drinkwater has been a lifelong champion of equality for women in many areas of life well before it was widely accepted. Her “walking the walk” of women breaking barriers in traditional male roles in administration and leadership is exemplified by her election as the first woman president of the American College of Sports Medicine in 1988. Some of the controversial areas in which Barbara was vocal in the arena of women in sport, besides triad/relative energy deficiency in sport, include increased opportunity and participation, total equality, acceptance of diversity, intolerance of harassment and abuse, and fairness with transgender athletes. She co-founded the evidence-based advocacy group on the international stage known as Women Sport International. As a physiologist, Barbara has had a major influence on attention to the health of the female athlete, and she produced the original pioneering work in the field. Her impactful study, “Bone mineral density after resumption of menses in amenorrheic athletes,” was published in the Journal of the American Medical Association in 1986. Since that time, the female athlete triad has set the stage for research and treatment to enhance women in physical activity at all levels.

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David P. Looney, Mark J. Buller, Andrei V. Gribok, Jayme L. Leger, Adam W. Potter, William V. Rumpler, William J. Tharion, Alexander P. Welles, Karl E. Friedl and Reed W. Hoyt

ECTemp is a heart rate (HR)-based core temperature (CT) estimation algorithm mainly used as a real-time thermal-work strain indicator in military populations. ECTemp may also be valuable for resting CT estimation, which is critical for circadian rhythm research. This investigation developed and incorporated a sigmoid equation into ECTemp to better estimate resting CT. HR and CT data were collected over two calorimeter test trials from 16 volunteers (age, 23 ± 3 yrs; height, 1.72 ± 0.07 m; body mass, 68.5 ± 8.1 kg) during periods of sleep and inactivity. Half of the test trials were combined with ECTemp’s original development dataset to train the new sigmoid model while the other was used for model validation. Models were compared by their estimation accuracy and precision. While both models produced accurate CT estimates, the sigmoid model had a smaller bias (−0.04 ± 0.26°C vs. −0.19 ± 0.29°C) and root mean square error (RMSE; 0.26°C vs. 0.35°C). ECTemp is a validated HR-based resting CT estimation algorithm. The new sigmoid equation corrects lower CT estimates while producing nearly identical estimates to the original quadratic equation at higher CT. The demonstrated accuracy of ECTemp encourages future research to explore the algorithm’s potential as a non-invasive means of tracking CT circadian rhythms.

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Ken Pitetti, Ruth Ann Miller and E. Michael Loovis

Male youth (8–18 years) with intellectual disability (ID) demonstrate motor proficiency below age-related competence capacities for typically developing youth. Whether below-criteria motor proficiency also exists for females with ID is not known. The purpose of this study was to determine if sex-specific differences exist in motor proficiency for youth with ID. The Bruininks-Oseretsky Test of Motor Proficiency was used to measure motor proficiency: six items for upper limb coordination, seven items for balance, and six items for bilateral coordination. One hundred and seventy-two (172) males and 85 females with ID but without Down syndrome were divided into five age groups for comparative purposes: 8–10, 11–12, 13–14, 15–16, and 17–21 years. Males scored sufficiently higher than females to suggest that sex data should not be combined to established Bruininks-Oseretsky Test of Motor Proficiency standards for upper limb coordination, balance, and bilateral coordination subtests.

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Zachary R. Weber, Divya Srinivasan and Julie N. Côté

The objectives of this study were to assess the sex-specific relationships between motor and sensory adaptations to repetitive arm motion–induced neck/shoulder fatigue, and to measure how additional sensory stimulation affects these adaptations. Twenty-three participants performed two sessions of a repetitive pointing task until scoring 8 on the Borg CR10 scale for neck/shoulder exertion or for a maximum of 45 min, with and without sensory stimulation (i.e., light touch) applied on the fatiguing shoulder. Just before reaching the task termination criteria, all participants showed changes in mean and variability of arm joint angles and experienced a fivefold increase in anterior deltoid sensory threshold in the stimulus-present condition. Women with the greatest increases in anterior deltoid sensory thresholds demonstrated the greatest increases in shoulder variability (r = .66), whereas men with the greatest increases in upper-trapezius sensory thresholds demonstrated the greatest changes in shoulder angle (r = −.60) and coordination (r = .65) variability. Thus, sensory stimulation had no influence on time to termination but affected how men and women differently adapted, suggesting sex differences in sensorimotor fatigue response mechanisms.

Open access

D. Enette Larson-Meyer, Kathleen Woolf and Louise Burke

Nutrition assessment is a necessary first step in advising athletes on dietary strategies that include dietary supplementation, and in evaluating the effectiveness of supplementation regimens. Although dietary assessment is the cornerstone component of the nutrition assessment process, it should be performed within the context of a complete assessment that includes collection/evaluation of anthropometric, biochemical, clinical, and environmental data. Collection of dietary intake data can be challenging, with the potential for significant error of validity and reliability, which include inherent errors of the collection methodology, coding of data by dietitians, estimation of nutrient composition using nutrient food tables and/or dietary software programs, and expression of data relative to reference standards including eating guidance systems, macronutrient guidelines for athletes, and recommended dietary allowances. Limitations in methodologies used to complete anthropometric assessment and biochemical analysis also exist, as reference norms for the athlete are not well established and practical and reliable biomarkers are not available for all nutrients. A clinical assessment collected from history information and the nutrition-focused physical exam may help identify overt nutrient deficiencies but may be unremarkable in the well-trained athlete. Assessment of potential food-drug interactions and environmental components further helps make appropriate dietary and supplement recommendations. Overall, the assessment process can help the athlete understand that supplement intake cannot make up for poor food choices and an inadequate diet, while a healthy diet helps ensure maximal benefit from supplementation. Establishment of reference norms specifically for well-trained athletes for the nutrition assessment process is a future research priority.

Open access

Ina Garthe and Ronald J. Maughan

In elite sport, where opponents are evenly matched, small factors can determine the outcome of sporting contests. Not all athletes know the value of making wise nutrition choices, but anything that might give a competitive edge, including dietary supplements, can seem attractive. Between 40% and 100% of athletes typically use supplements, depending on the type of sport, level of competition, and the definition of supplements. However, unless the athlete has a nutrient deficiency, supplementation may not improve performance and may have a detrimental effect on both performance and health. Dietary supplements are classified as a subcategory of food, so manufacturers are not required to provide evidence of product safety and efficacy, nor obtain approval from regulatory bodies before marketing supplements. This creates the potential for health risks, and serious adverse effects have been reported from the use of some dietary supplements. Athletes who compete in sports under an anti-doping code must also realize that supplement use exposes them to a risk of ingesting banned substances or precursors of prohibited substances. Government systems of regulations do not include specific laboratory testing for banned substances according to the WADA list, so a separate regulatory framework to evaluate supplements for their risk of provoking a failed doping test is needed. In the high-performance culture typical of elite sport, athletes may use supplements regardless of possible risks. A discussion around medical, physiological, cultural, and ethical questions may be warranted to ensure that the athlete has the information needed to make an informed choice.