Supramaximal Interval Running Prescription in Australian Rules Football Players: A Comparison Between Maximal Aerobic Speed, Anaerobic Speed Reserve, and the 30-15 Intermittent Fitness Test.

ABSTRACT: Collison, J, Debenedictis, T, Fuller, JT, Gerschwitz, R, Ling, T, Gotch, L, Bishop, B, Sibley, L, Russell, J, Hobbs, A, and Bellenger, CR. Supramaximal interval running prescription in Australian Rules Football players: A comparison between maximal aerobic speed, anaerobic speed reserve and the 30-15 intermittent fitness test. J Strength Cond Res 36(12): 3409-3414, 2022-Accurate prescription of supramaximal interval running during Australian Rules Football (AF) preparatory periods is important to facilitate the specific targeting of physiological and neuromuscular adaptation. This study compared the variability in supramaximal interval running performance prescribed by proportion of maximal aerobic speed (MAS), anaerobic speed reserve (ASR), and 30-15 intermittent fitness test (30-15IFT) terminal speed. Seventeen male junior AF players first completed assessments of MAS, ASR, and 30-15IFT in a randomized order. They subsequently performed supramaximal interval running trials (15 seconds on: 15 seconds off until volitional exhaustion) at 120% MAS, 20% ASR, and 95% 30-15IFT in a randomized order. Variability in time to exhaustion (TTE) for each prescription method was calculated as the mean of the square root of the squared difference between the individual value and the mean value, and it was compared via repeated-measures analysis of variance with statistical significance set at p ≤ 0.05. Time to exhaustion during supramaximal interval running was not different between the prescription methods ( p = 0.58). Time to exhaustion residuals were reduced when prescribed by ASR compared with MAS (standardized mean difference [SMD] = -0.47; 29%); however, confidence intervals about this reduction indicated that there was some uncertainty in this finding (SMD = -1.03 to 0.09; p = 0.09). Trivial differences in TTE residuals were present when prescribed by 30-15IFT compared with MAS (SMD = -0.05 ± 0.59; p = 0.86). Although there was some uncertainty about the reduction in supramaximal interval running performance variability when prescribed by ASR compared with MAS, the 29% reduction exceeds the inherent error in TTE efforts (i.e., ∼9-15%) and may thus be considered practically meaningful. Reducing supramaximal interval running performance variability ensures similar physiological demand across individuals, potentially facilitating similar degrees of physiological adaptation.

Rationale and design of "Hearts & Parks": study protocol for a pragmatic randomized clinical trial of an integrated clinic-community intervention to treat pediatric obesity.

BACKGROUND: The prevalence of child and adolescent obesity and severe obesity continues to increase despite decades of policy and research aimed at prevention. Obesity strongly predicts cardiovascular and metabolic disease risk; both begin in childhood. Children who receive intensive behavioral interventions can reduce body mass index (BMI) and reverse disease risk. However, delivering these interventions with fidelity at scale remains a challenge. Clinic-community partnerships offer a promising strategy to provide high-quality clinical care and deliver behavioral treatment in local park and recreation settings. The Hearts & Parks study has three broad objectives: (1) evaluate the effectiveness of the clinic-community model for the treatment of child obesity, (2) define microbiome and metabolomic signatures of obesity and response to lifestyle change, and (3) inform the implementation of similar models in clinical systems. METHODS: Methods are designed for a pragmatic randomized, controlled clinical trial (n = 270) to test the effectiveness of an integrated clinic-community child obesity intervention as compared with usual care. We are powered to detect a difference in body mass index (BMI) between groups at 6 months, with follow up to 12 months. Secondary outcomes include changes in biomarkers for cardiovascular disease, psychosocial risk, and quality of life. Through collection of biospecimens (serum and stool), additional exploratory outcomes include microbiome and metabolomics biomarkers of response to lifestyle modification. DISCUSSION: We present the study design, enrollment strategy, and intervention details for a randomized clinical trial to measure the effectiveness of a clinic-community child obesity treatment intervention. This study will inform a critical area in child obesity and cardiovascular risk research-defining outcomes, implementation feasibility, and identifying potential molecular mechanisms of treatment response. CLINICAL TRIAL REGISTRATION: NCT03339440 .

Association of Physical Activity With Income, Race/Ethnicity, and Sex Among Adolescents and Young Adults in the United States: Findings From the National Health and Nutrition Examination Survey, 2007-2016.

Importance: Physical activity in youth is associated with adult health. Understanding the prevalence and factors of moderate to vigorous physical activity among adolescents and young adults will guide public health and policy efforts. Objectives: To describe the current patterns of physical activity and duration among adolescents and young adults and to identify the direction and magnitude of associations between physical activity and income, race/ethnicity, and sex. Design, Setting, and Participants: This cross-sectional secondary data analysis used the self-reported physical activity data of adolescents and young adults from the National Health and Nutrition Examination Survey from 2007 through 2016. This data set is a multistage probability sample of the noninstitutionalized US population and allows estimates that represent the US population. The years 2007 through 2016 were selected because of the consistent physical activity questions during this period. Adolescents and young adults aged 12 to 29 years who responded to the survey were included. Individuals who were underweight were excluded. Data analysis was performed from October 17, 2017, to April 27, 2018. Main Outcomes and Measures: Self-reported physical activity duration and intensity. Results: Of the 9472 participants, 4771 (50.4%) were males, and the weighted mean age (range) was 20.6 (12-19) years. Across all demographic categories, females reported less physical activity than did their male counterparts. White adolescent males were most likely (89.3%; 95% CI, 86.5%-92.1%) and black females aged 18 to 24 years were least likely (45%; 95% CI, 39.0%-51.0%) to report any physical activity. Among those who were active, black males aged 18 to 24 years reported the longest duration of activity (77.9 minutes per day; 95% CI, 66.4-89.3 minutes per day), and black females aged 25 to 29 years reported the shortest duration of activity (33.2 minutes per day; 95% CI, 28.1-38.2 minutes per day). In adjusted models, younger age, white race, and higher income were associated with greater physical activity. Conclusions and Relevance: Female adolescents and young adults were not meeting the recommended guidelines for physical activity, and substantial disparities by race and income levels were noted. These data highlight opportunities for targeted physical activity programming and policy efforts.