Background: Emerging research shows that the composition of movement behaviors throughout the day (physical activities, sedentary behaviors, sleep) is related to indicators of health, suggesting previous research that isolated single movement behaviors maybe incomplete, misleading, and/or unnecessarily constrained. Methods: This brief report summarizes evidence to support a 24-hour movement behavior paradigm and efforts to date by a variety of jurisdictions to consult, develop, release, promote, and study 24-hour movement guidelines. It also introduces and summarizes the accompanying series of articles related specifically to 24-hour movement guidelines for the early years. Results: Using robust and transparent processes, Canada, Australia, New Zealand, South Africa, and the World Health Organization have developed and released 24-hour movement guidelines for the early years: an integration of physical activity, sedentary behavior, and sleep. Other countries are exploring a similar approach and related research is expanding rapidly. Articles related to guideline development in South Africa, the United Kingdom, Australia, and by the World Health Organization are a part of this special series. Conclusions: A new paradigm employing 24-hour movement guidelines for the early years that combines recommendations for movement behaviors across the whole day is gaining momentum across the globe.
Introducing 24-Hour Movement Guidelines for the Early Years: A New Paradigm Gaining Momentum
Mark S. Tremblay
2014 Global Summit on the Physical Activity of Children
Mark S. Tremblay
Unmasking the Political Power of Physical Activity Research: Harnessing the “Apolitical-Ness” as a Catalyst for Addressing the Challenges of Our Time
Eun-Young Lee and Mark S. Tremblay
Long-Term Importance of Fundamental Motor Skills: A 20-Year Follow-Up Study
Meghann Lloyd, Travis J. Saunders, Emily Bremer, and Mark S. Tremblay
The purpose of this study was to investigate the potential long-term association of motor skill proficiency at 6 years of age and self-reported physical activity (PA) at age 26. Direct motor performance data were collected in 1991 with a follow-up study occurring in 1996, and then indirect questionnaires (self-report) administered in 2001 and 2011. In 2011, 17 participants who were identified as either having high motor proficiency (HMP) or low motor proficiency (LMP) in 1991 completed a series of 4 questionnaires. Analyses were conducted to determine whether there were differences between groups for motor skill proficiency, PA, or sedentary behavior, and whether these outcomes were related across ages. Motor skill proficiency at age 6 was related to self-reported proficiency at age 16 (r = .77, p = .006), and self-reported proficiency between 16 and 26 years (r = .85, p = .001). Motor skill proficiency at age 6 was positively associated with leisure time PA at age 26 in females and participants in the HMP group. The results may provide preliminary evidence about the importance of how early motor skill proficiency relates to long-term PA. More research with larger sample sizes is needed to investigate the importance of motor skills over time.
Aging, Physical Activity, and Hormones in Women—A Review
Jennifer L. Copeland, Samuel Y. Chu, and Mark S. Tremblay
Women experience significant changes in endocrine function during aging. Decreasing levels of anabolic hormones may be associated with musculoskeletal atrophy and decrease in function that is observed in older women and, as a result, there has been an increase in the use of pharmacological hormone therapies. It is difficult to distinguish, however, between physiological changes that are truly age related and those that are associated with lifestyle factors such as physical activity participation. Some research has shown that circulating levels of anabolic hormones such as DHEA(S) and IGF-I in older women are related to physical activity, muscle function, and aerobic power. Exercise-intervention studies have generally shown that increasing age blunts the acute hormonal response to exercise, although this might be explained by a lower exercise intensity in older women. There have been relatively few studies that examine hormonal adaptations to exercise training. Physical activity might have an effect on hormone action as a result of changes in protein carriers and receptors, and future research needs to clarify the effect of age and exercise on these other components of the endocrine system. The value and safety of hormone supplements must be examined, especially when used in combination with an exercise program.
Factor Structure of Responses to the Portuguese Version of Questions About Screen Time–Based Sedentary Behavior Among Adolescents
Diego Augusto Santos Silva, Katie E. Gunnell, and Mark Stephen Tremblay
Background: This study aimed to examine the factor structure of responses to the Portuguese version of questions related to screen time–based sedentary behavior among adolescents. Methods: This cross-sectional study with a sample of 1083 adolescents aged 14–19 years was conducted in Brazil. The sample was randomly divided into 2 groups for an exploratory factor analysis and for a confirmatory factor analysis. Screen time was investigated by a Portuguese version of questions about time sitting in front of television, computer, and video games on weekdays and weekends. Results: Scree plots showed 2 factors with eigenvalues above 1. One factor was formed by items about television and computer use, and the other factor was formed by items about video game use. The exploratory factor analysis with 2 factors resulted in factor loadings above .60. A second model with 1 factor was estimated and resulted in factor loadings above .55. A confirmatory factor analysis was estimated based on the 2-factor exploratory factor analysis and goodness-of-fit statistics were adequate. Confirmatory factor analysis with 1 factor had goodness-of-fit statistics adequate. Conclusions: The Portuguese language version of self-report screen time had 2 possible factor solutions, and items demonstrated good factor structure with reasonable reliability making it suitable for use in the future studies.
Advancing the Debate on ‘Fitness Testing’ for Children: Perhaps We’re Riding the Wrong Animal
Meghann Lloyd, Rachel C. Colley, and Mark S. Tremblay
Relationship Between Active School Transport and Body Mass Index in Grades-4-to-6 Children
Richard Larouche, Meghann Lloyd, Emily Knight, and Mark S. Tremblay
The current investigation assessed the impact of active school transportation (AST) on average daily step counts, body mass index (BMI) and waist circumference in 315 children in Grades 4–6 who participated to Cycle 2 of the Canadian Assessment of Physical Literacy (CAPL) pilot testing. T-tests revealed a significant association between AST and lower BMI values (18.7 ± 3.3 vs. 19.9 ± 3.8 kg/m2). The active commuters accumulated an average of 662 more steps per day, and their waist circumference was lower by an average of 3.1 cm, but these differences were not statistically significant. ANCOVA analyses controlling for age and step counts, found trends toward lower BMI and waist circumference values among the active commuters. These results suggest that AST may be a valid strategy to prevent childhood obesity; further research is needed to determine more precisely the impact of AST on body composition, and the direction of the relationship.
Comparative Validity Assessment of Five Activity Monitors: Does Being a Child Matter?
Michelle R. Stone, Dale W. Esliger, and Mark S. Tremblay
The purpose of this study was to determine the effects of age and leg length on the energy-expenditure predictions of five activity monitors. Participants (N = 86, ages 8–40 years) performed three progressive bouts of treadmill activity ranging from 4 to 12 km/hr. Differences between measured energy expenditure (VO2) and activity-monitor-predicted energy expenditure were assessed across five leg length categories to determine the influence of leg length. Accelerometer counts or pedometer steps along with age, weight, and leg length accounted for 85–94% of measured energy expenditure. The addition of age and leg length as predictor variables explained a larger amount of variance in energy expenditure across all speeds. Differences in leg length and age might affect activity-monitor validity and, therefore, should be controlled for when estimating physical activity energy expenditure.
Impact of the Active Healthy Kids Canada Report Card: A 10-Year Analysis
Mark S. Tremblay, Joel D. Barnes, and Jennifer Cowie Bonne
For 20 years Active Healthy Kids Canada (AHKC) has worked to inspire the country to engage all children and youth in physical activity (PA). The primary vehicle to achieve this is the AHKC Report Card on Physical Activity for Children and Youth, which has been released annually since 2005. Using 10 years of experience with this knowledge translation and synthesis mechanism, this paper aggregates and consolidates diverse evidence demonstrating the impact of the Report Card and related knowledge translation activities. Over the years many evaluations, consultations, assessments, and surveys have helped inform changes in the Report Card to improve its impact. Guided by a logic model, the various assessments have traversed areas related to distribution and reach, meeting stakeholder needs, use of the Report Card, its influence on policy, and advancing the mission of AHKC. In the past 10 years, the Report Card has achieved > 1 billion media impressions, distributed > 120,000 printed copies and > 200,000 electronic copies, and benefited from a collective ad value > $10 million. The Report Card has been replicated in 14 countries, 2 provinces, 1 state and 1 city. AHKC has received consistent positive feedback from stakeholders and endusers, who reported that the Report Card has been used for public awareness/education campaigns and advocacy strategies, to strengthen partnerships, to inform research and program design, and to advance and adjust policies and strategies. Collectively, the evidence suggests that the Report Card has been successful at powering the movement to get kids moving, and in achieving demonstrable success on immediate and intermediate outcomes, although the long-term goal of improving the PA of Canadian children and youth remains to be realized.