Meeting USDHHS Physical Activity Guidelines and Health Outcomes.

Current public health physical activity (PA) guidelines suggest ≥500 METmin/week of PA, with additional benefits beyond 1000 METmin/week (i.e., a dose response). Revised U.S. PA guidelines are scheduled for 2018. The purpose was to relate health markers (blood pressure, percent fat, BMI, blood glucose, cholesterol, and cardiorespiratory fitness) to verify the dose response for PA guidelines revision. 505 non-smoking participants self-reported PA behaviors and completed medical screening. MANCOVA controlling for age and gender determined the relation between health markers and PA. MANCOVA indicated significantly (P<.001) different health markers of percent fat, BMI, glucose, and treadmill time as a function of PA. Post-hoc Helmert contrasts (1] <500 METmin/week vs. ≥500 METmin/week and 2] 500 to <1000 METmin/week vs. ≥1000 METmin/week) indicated that meeting the PA guidelines was associated with better health markers and higher cardiorespiratory fitness. Effect sizes were greater for contrast 1 than for contrast 2, suggesting a plateauing effect. Revised public health guidelines should consider achievement of ≥500 METmin/week to be most important, with additional modest gain thereafter. Revised PA guidelines should stress the importance of achieving 500-1000 METmin/week.

Better Health-Related Fitness in Youth: Implications for Public Health Guidelines.

Public health guidelines for physical activity (PA) behaviors are being updated with 2018 as a proposed release date. Currently, ≥60 minutes of daily PA are recommended for youth. Thus, the purpose of this study was to investigate the association between reported days of aerobic PA and health-related fitness (HRF). Participants included 4448 students in grades 6-8. Self-reported days of ≥60 minutes of aerobic PA was obtained. HRF was assessed with FitnessGram. Discriminant analysis indicated that weekly days of aerobic PA related to HRF. Adolescents who participated in ≥5 days of weekly aerobic PA generally had better fitness results than those with ≤4 days. Chi-square analyses indicated the highest percentages of adolescents in the FitnessGram Healthy Fitness Zone™ (HFZ) for each test item were those with ≥5 days of aerobic PA. These findings provided initial support that the impact of aerobic PA on HRF plateaus at 5 days per week. Thus, adolescents may be able to improve HRF even if they do not meet the currently recommended guidelines for daily PA.

An Analysis of the Medical Costs of Obesity for Fifth Graders in California and Texas.

The prevalence of childhood obesity in the United States increased more than three-fold from 1976 - 1980 to 2007 - 2008. The Presidential Youth Fitness Program's FitnessGram® is the current method recommended by the President's Council on Fitness, Sports & Nutrition for assessing health-related fitness factors, including body composition. FitnessGram® data from California and Texas, the two most populous states, over a three-year time span indicate that more than one-third of fifth grade students, typically ten-year-olds, are obese. Previous studies report that an obese ten-year-old child who remains obese into adulthood will incur elevated direct medical costs beyond his or her normal-weight peers over a lifetime. The recommended elevated cost estimates are approximately $12,660 when comparing against a normal-weight child who gains weight as an adult and approximately $19,000 compared to a child who remains at normal weight as an adult. By applying these figures to FitnessGram® results from California and Texas, each group of fifth grade students in each of the two states will incur between $1.4 and $3.0 billion in direct medical costs over a lifetime. When the percentage of obese fifth graders is extrapolated to the rest of the United States' 4 million ten-year-olds, this results in more than $17 billion (accounting for adulthood weight gain) or $25 billion (not accounting for adulthood weight gain) in added direct lifetime medical costs attributable to obesity for this single-year age cohort. This information should be used to influence spending decisions and resource allocation to obesity reduction and prevention efforts.

Strategic Priorities for Physical Activity Surveillance in the United States.

PURPOSE: Develop strategic priorities to guide future physical activity surveillance in the United States. METHODS: The Centers for Disease Control and Prevention and the American College of Sports Medicine convened a scientific roundtable of physical activity and measurement experts. Participants summarized the current state of aerobic physical activity surveillance for adults, focusing on practice and research needs in three areas: 1) behavior, 2) human movement, and 3) community supports. Needs and challenges for each area were identified. At the conclusion of the meeting, experts identified one overarching strategy and five strategic priorities to guide future surveillance. RESULTS: The identified overarching strategy was to develop a national plan for physical activity surveillance similar to the U.S. National Physical Activity Plan for promotion. The purpose of the plan would be to enhance coordination and collaboration within and between sectors, such as transportation and public health, and to address specific strategic priorities identified at the roundtable. These strategic priorities were used 1) to identify and prioritize physical activity constructs; 2) to assess the psychometric properties of instruments for physical activity surveillance; 3) to provide training and technical assistance for those collecting, analyzing, or interpreting surveillance data; 4) to explore accessing data from alternative sources; and 5) to improve communication, translation, and dissemination about estimates of physical activity from surveillance systems. CONCLUSION: This roundtable provided strategic priorities for physical activity surveillance in the United States. A first step is to develop a national plan for physical activity surveillance that would provide an operating framework from which to execute these priorities.

Implementing Policies to Enhance Physical Education and Physical Activity in Schools.

The purpose of this commentary is to provide an overview of national physical activity recommendations and policies (e.g., from the Institute of Medicine, National Physical Activity Plan, and Centers for Disease Control and Prevention) and to discuss how these important initiatives can be implemented in local schools. Successful policies are illustrated. Specific strategies and ideas are shared regarding how physical educators can assert themselves and impart their knowledge in an effort to build support for policy implementations that enhance the delivery of physical education and physical activity in their schools and communities.

Longitudinal trajectories of physical activity in women using latent class growth analysis: The WIN Study.

PURPOSE: This study aimed (1) to examine the longitudinal trajectories in objectively measured physical activity (PA); (2) to identify unknown (i.e., latent) subgroups with distinct trajectories; and (3) to examine the correlates of latent subgroups among community dwelling women. METHODS: The study sample included a total of 669 women from the Women's Injury Study, a 5-year prospective cohort study conducted from 2007 in the Southwest Central region of the US. Pedometer-based step-count data across 18 consecutive months were fitted to a latent growth model (LGM) and a latent class growth model (LCGM). Baseline characteristics were regressed on latent class membership. RESULTS: The longitudinal change in PA was best fit to a piecewise LGM with seasonal transitions. Significantly increased and decreased levels of PA were observed during the spring, fall, and winter, respectively (p < 0.001). Three latent subgroups with distinct PA trajectories were identified (low-active (46.8%), somewhat-active (41.3%), and active (11.9%)). Age and body fat percentage at the baseline significantly explained the likelihoods of being in low-active subgroup. CONCLUSION: Seasonal variations in PA among women were observed but may not be practically significant. A relatively large portion of the sample showed low levels of PA for long periods. Intervention strategies should be considered for women who are overweight or obese, and aged >40 years old to promote PA during the life course.

Advancing kinesiology through improved peer review.

Peer review of scholarship is essential to journal quality, evidence, knowledge advancement, and application of that knowledge in any field. This commentary summarizes recent literature on issues related to peer-review quality and current review practice in kinesiology and provides recommendations to improve peer review in kinesiology journals. We reviewed the literature on the characteristics of peer review in scientific journals and describe the status of peer review in kinesiology journals. Although the majority of scholars and editors strongly support the peer-review process, systematic research in several disciplines has shown somewhat positive but mixed results for the efficacy of peer review in evaluating the quality of and improving research reports. Past recommendations for improvement have focused on agreement between reviewers, standards for evaluating quality, and clarification of the editorial team roles. Research on interventions, however, indicates that improving reviewer performance is difficult. The specific research on peer review in kinesiology is limited. Six recommendations to improve peer review are proposed: publishing clear evaluation standards, establishing collaborative evaluation procedures and editorial team roles, utilizing online submission data to help improve reviewer comments, creating author appeals procedures, protecting reviewer time commitments, and improving reviewer recognition. There is considerable variation in peer-review criteria and procedures in kinesiology, and implementing several reasonable improvements may advance knowledge development and the field of kinesiology.

Musculoskeletal risk factors as predictors of injury in community-dwelling women.

BACKGROUND: Participating in health-related physical activity (PA) may increase risk for musculoskeletal injury (MSI). PURPOSE: This study aimed to estimate the prevalence of structural/biomechanical risk factors in community-dwelling women and associated risk for incidence of MSI in women who are physically active. METHODS: The Women's Injury study is a surveillance of PA behaviors and MSI in women age 20-83 yr. An orthopedic examination was performed before entry into the study to assess presence of structural/biomechanical risk factors. A total of 886 women completed data collection by reporting weekly PA behavior and MSI for up to 3 yr (2007-2009), with the average participant enrolled for 98 wk. To estimate MSI risk associated with each risk factor separately, time to first MSI was modeled using proportional hazard regression with time-dependent PA covariates, controlling for age, body mass index, and previous injury. RESULTS: Over the course of the study, 236 of the women (26.6%) reported at least one MSI that was PA related. We found a significant association between the number of high flexibility risk factors and PA-related injury at all levels of PA exposure (HR = 1.15 and confidence interval (CI) = 1.04-1.27 for moderate-to-vigorous PA; HR = 1.16 and CI = 1.05-1.28 for moderate PA; HR = 1.15 and CI = 1.04-1.27 for vigorous PA). CONCLUSIONS: When participating at any level of PA for health benefits, women with hypermobility in multiple muscle groups or joints should be watchful for musculoskeletal symptoms and should be counseled not to ignore symptoms when they first occur.

Association of multiple adiposity exposures and cardiorespiratory fitness with all-cause mortality in men: the Cooper Center Longitudinal Study.

OBJECTIVE: To examine the additive effects of an increased number of positive adiposity exposures on all-cause mortality in men before and after stratification by cardiorespiratory fitness (CRF) level. PATIENTS AND METHODS: A total of 36,836 men underwent a physical examination at the Cooper Clinic from January 1, 1971, through December 31, 2006. Exposures included body mass index, waist circumference, percentage of body fat, and CRF as determined by duration of a maximal exercise test. Participants were identified as being either obese (positive) or nonobese (negative) for each adiposity exposure and then grouped into 4 categories: group 1, negative for all adiposity exposures; group 2, positive for any 1 exposure; group 3, positive for any 2 exposures; and group 4, positive for all exposures. Then CRF was grouped as fit or unfit on the basis of the upper 80% and lower 20% of the age-standardized CRF distribution as previously reported in the Cooper Center Longitudinal Study. Hazard ratios were computed with Cox regression analysis. RESULTS: A total of 2294 deaths occurred during a mean ± SD of 15.5 ± 8.1 years of follow-up. Adjusted hazard ratios across adiposity groups were 1.0 (referent), 1.05, 1.37, and 1.87 for groups 1 through 4, respectively (P for trend <.001). Mortality rates were significantly lower within each of the first 3 adiposity groups in fit compared with unfit men (P<.009 for all comparisons). CONCLUSION: An increasing number of positive adiposity exposures were associated with increased mortality in men. Because moderate to high CRF attenuated mortality rates in all adiposity groups, measurement of CRF should be included for identifying men at increased risk for all-cause mortality.

2014 consensus statement from the first Economics of Physical Inactivity Consensus (EPIC) conference (Vancouver).

This article describes major topics discussed from the 'Economics of Physical Inactivity Consensus Workshop' (EPIC), held in Vancouver, Canada, in April 2011. Specifically, we (1) detail existing evidence on effective physical inactivity prevention strategies; (2) introduce economic evaluation and its role in health policy decisions; (3) discuss key challenges in establishing and building health economic evaluation evidence (including accurate and reliable costs and clinical outcome measurement) and (4) provide insight into interpretation of economic evaluations in this critically important field. We found that most methodological challenges are related to (1) accurately and objectively valuing outcomes; (2) determining meaningful clinically important differences in objective measures of physical inactivity; (3) estimating investment and disinvestment costs and (4) addressing barriers to implementation. We propose that guidelines specific for economic evaluations of physical inactivity intervention studies are developed to ensure that related costs and effects are robustly, consistently and accurately measured. This will also facilitate comparisons among future economic evidence.

Relations between sedentary behavior and FITNESSGRAM healthy fitness zone achievement and physical activity.

PURPOSE: To investigate the relations between sedentary behaviors and health-related physical fitness and physical activity in middle school boys and girls. METHODS: Students (n = 1515) in grades 6-8 completed the Youth Risk Behavior Survey sedentary behavior questions, the FITNESSGRAM physical fitness items, and FITNESSGRAM physical activity self-report questions. RESULTS: When students reported ≤ 2 hours per day of sedentary behaviors, their odds of achieving the FITNESSGRAM Healthy Fitness Zone for aerobic capacity, muscular strength and endurance, flexibility, and body composition increased. Similarly, the odds of achieving physical activity guidelines for children increased when students reported ≤ 2 hours per day of sedentary behaviors. CONCLUSIONS: Results illustrate the importance of keeping sedentary behaviors to ≤ 2 hours per day in middle school children, thus increasing the odds that the student will achieve sufficient health-related fitness benefits and be more likely to achieve the national physical activity guidelines.

Costs associated with women's physical activity musculoskeletal injuries: the women's injury study.

BACKGROUND: Despite benefits of physical activity (PA), exercise is also associated with risks. Musculoskeletal injury (MSI) risk increases with exercise frequency/intensity. MSI is associated with costs including medical care and time lost from work. PURPOSE: To evaluate the economic costs associated with PA-related MSIs in community-dwelling women. METHOD: Participants included 909 women in the Women's Injury Study reporting PA behaviors and MSI incidence weekly via the Internet for up to 3 years (mean follow-up 1.89 years). Participants provided consent to obtain health records. Costs were estimated by medical records and self-reports of medical care. Components included physician visits, medical facility contacts, medication costs, and missed work. RESULTS: Of 909 participants, 243 reported 323 episodes of expenditure or contact with the health care system associated with PA. Total costs of episodes ranged from $0-$18,934. Modal cost was $0 (mean = $433 ± $1670). Costs were positively skewed with nearly all participants reporting no or very low costs. CONCLUSIONS: About 1 in 4 community-dwelling women who are physically active experienced a PA-related MSI. The majority of injuries were minor, and large expenses associated with MSI were rare. The long-term health benefits and costs savings resulting from PA likely outweigh the minor costs associated with MSI from a physically-active lifestyle.

Physical activity and musculoskeletal injuries in women: the Women's Injury Study.

BACKGROUND: Increased injury rates have been associated with physical activity (PA). The differences in musculoskeletal injury (MSI) characteristics resulting from PA, versus those unrelated to PA, are unknown. We describe the pattern of PA and non-PA MSI incurred by community-dwelling women. METHODS: Data were extracted from the Women's Injury Study, a web-based observational study that tracked weekly PA behaviors and self-reported MSI of 909 community-dwelling women ages 20-83 years. The primary outcome was self-reported MSI that interrupted daily activities ≥2 days and/or required treatment from a health care provider. Follow-up telephone reporting of MSIs allowed further description of injuries. Mixed effects logistic regression was used to identify injury sites associated with PA, controlling for age, body mass index, previous injury, and use of alcohol. RESULTS: Incidence of PA and non-PA MSIs were comparable; some differences in injury characteristics were evident across 83,241 person-weeks of reporting. Non-PA MSIs were more likely to come on "suddenly" (54% vs. 8%) and commonly involved head/jaw/neck injuries. Reported PA-related MSIs were less likely to require health care provider treatment (60% vs. 80%) and resulted in less missed days of work/school (11%) versus non-PA MSIs (17%). Compared to non-PA related injuries, PA-related injuries were more likely to involve the lower (odds ratio [OR]=3.10, p=0.002) or upper limbs (OR=2.54, p=0.01) and less likely to involve the head/jaw/neck (OR=0.21, p=0.002). CONCLUSION: There are some differences in mechanisms of injury, the distribution of injuries by anatomical location, and the treatment of injuries depending on aerobic activity participation, although absolute rates of MSI were comparable.

Meeting physical activity guidelines and health-related fitness in youth.

BACKGROUND: National physical activity guidelines have been developed for Americans. Interest lies in the relationship between meeting the national physical activity guidelines and physical fitness outcomes in youth. Theoretically, those who meet the physical activity guidelines are more physically fit, which translates to better health and reduced risk. PURPOSE: To examine the relationship between youth self-reported physical activity behaviors sufficient to meet DHHS Physical Activity Guidelines for Americans and an external health criterion: achievement of the FITNESSGRAM(®) Healthy Fitness Zone™ (HFZ). METHODS: Logistic regression was used to examine achievement of the HFZ for three physical fitness measures (i.e., aerobic capacity, BMI, and muscle fitness) separately, and for all three combined, based on self-reported physical activity of 7 days per week for aerobic activity and ≥3 days per week of muscle-strengthening activity. One model examined the direct relationship between physical activity and fitness measures, and a second model assessed the same relationship while controlling for gender, age, ethnicity, economic status, and school. Data were collected during the 2009-2010 academic year and analyzed in 2012. RESULTS: Adolescents failing to meet national aerobic and muscle-strengthening physical activity guidelines have higher odds of not achieving healthy physical fitness levels of aerobic capacity, BMI, muscle fitness, and the combination of all three. An increase in the number of days of aerobic activity was related to decreased odds of being in the Needs Improvement Fitness Zone. CONCLUSIONS: The findings provide further support that meeting the national physical activity guidelines produces health benefits for youth.

District and school physical education policies: implications for physical education and recess time.

BACKGROUND: The relationship between physical education (PE) policies and children's PE and recess time is not well understood. PURPOSE: The purpose of this study is to assess the association of district and school PE policies, the PE environment, and PE and recess time. METHODS: Key informants in 65 schools from 9 states completed instruments assessing district and school PE policies, the school PE environment, and time in PE and recess. RESULTS: Few significant associations were found between PE policies and PE or recess minutes; no policies were associated with both. A number of PE environmental variables were associated with both policies and time in PE and recess. CONCLUSIONS: PE policies, their implementation, and PE environmental variables can have important implications for recess time. Some school PE environment measures designed to improve PE may result in PE time limitations. Deficiencies in PE and recess time are not likely to be effectively addressed through policy adoption alone.

School physical activity policy assessment.

BACKGROUND: Physical activity (PA) levels in schools vary widely, and there is interest in studying how student PA accrual relates to school policy and environmental conditions. School PA policy research, however, is in its infancy and generalizable measurement tools do not exist. We developed and assessed reliability of items on the School Physical Activity Policy Assessment (S-PAPA), an instrument designed to assess school PA policy related to physical education (PE), recess, and other opportunities. METHODS: To develop items, we perused associated literature, examined existing instruments, and consulted school policy makers. For test-retest reliability assessment, 31 elementary school PE teachers completed the survey twice, 14 days apart. RESULTS: S-PAPA uses open-ended, dichotomous, multichotomous, and checklist formatting and has 3 modules: 1) Physical Education (47 items), 2) Recess (27 items), and 3) Other Before, During, and After School Programs (15 items). Responses to more than 95% of items were highly related between Times 1 and 2. Generally, physical education and recess items had fair to substantial levels of agreement, and items about other school PA programs had fair to perfect agreement. CONCLUSIONS: Test-retest results suggest S-PAPA items are reliable and useful in assessing PA policies in elementary schools.

Prevalence of muscle-strengthening activities in women: the WIN study.

BACKGROUND: Aerobic and muscle-strengthening activities are related to morbidities and mortality. Resistance exercise/strength training items are included in national surveys, but the manner in which muscle-strengthening activity is queried varies among these surveys. PURPOSE: The purpose of this study was to use different self-report measures to examine the prevalence of meeting the 2008 Physical Activity Guidelines for Americans regarding muscle-strengthening activities among women. METHODS: We surveyed 606 community-dwelling women at 4 points in time across a 1.5- to 3-year time period to determine whether the respondents met the national physical activity guidelines for performing muscle-strengthening activities ≥ 2 days per week. RESULTS: Results were consistent across time but depended on the manner in which the question was asked. If asked to reflect over the past month or a general question about the typical number of days engaged, approximately 40% of women reported engaging in ≥ 2 days per week of resistance exercise/strength training. However, when reports were obtained weekly for 13 weeks, only approximately 18% of respondents met the guidelines. CONCLUSION: Results indicate that the timing and nature of questioning can substantially influence the self-reported prevalence of muscle-strengthening physical activities for community-dwelling women.

Meeting physical activity guidelines and musculoskeletal injury: the WIN study.

INTRODUCTION: The United States Department of Health and Human Services disseminated physical activity (PA) guidelines (PAGs) for Americans in 2008. The guidelines are based on appropriate quantities of moderate-to-vigorous aerobic PA and resistance exercise (RE) associated with decreased morbidity and mortality risk and increased health benefits. However, increases in PA levels are associated with increased risk of musculoskeletal injuries (MSIs). We related the amount and type of PA conducted on a weekly basis with the risk of MSI. METHODS: A prospective, observational study using weekly Internet tracking of moderate-to-vigorous PA and RE behaviors and MSIs in 909 community-dwelling women for up to 3 yr was conducted. The primary outcome was self-reported MSIs (total, PA related, and non-PA related) interrupting typical daily work and/or exercise behaviors for ≥ 2 d or necessitating health care provider visit. RESULTS: Meeting versus not meeting PAGs was associated with more MSIs during PA (HR = 1.39, 95% confidence interval [CI] = 1.05-1.85, P = 0.02) but was not associated with MSIs unrelated to PA (HR = 0.99, 95% CI = 0.75-1.29, P = 0.92) or with MSIs overall (HR = 1.15, 95% CI = 0.95-1.39, P = 0.14). CONCLUSIONS: The results illustrate the risk of MSI with PA. MSI risk rises with increasing PA. Despite this modest increase in MSIs, the known benefits of aerobic and resistance PAs should not hinder physicians from encouraging patients to meet current PAGs for both moderate-to-vigorous exercise and RE behaviors with the intent of achieving health benefits.

Framework for physical activity as a complex and multidimensional behavior.

CONTEXT: The selection of the most psychometrically appropriate self-report tool(s) to measure specific physical activity constructs has been a challenge for researchers, public health practitioners, and clinicians, alike. The lack of a reasonable gold standard measure and inconsistent use of established and evolving terminology have contributed to these challenges. The variation of self-report measures and quality of the derived summary estimates could be attributed to the absence of a standardized conceptual framework for physical activity. OBJECTIVE: To present a conceptual framework for physical activity as a complex and multidimensional behavior that differentiates behavioral and physiological constructs of human movement. PROCESS: The development of a conceptual framework can provide the basic foundation from which to standardize definitions, guide design and development of self-report measures, and provide consistency during instrument selection. CONCLUSIONS: Based on our proposed conceptual framework for physical activity, we suggest that physical activity is more clearly defined as the behavior that involves human movement, resulting in physiological attributes including increased energy expenditure and improved physical fitness. Utilization of the proposed conceptual framework can result in better instrument choices and consistency in methods used to assess physical activity and sedentary behaviors across research and public health practice.