Patricia A. Eisenman

Quantifying Physical Activity via Pedometry in Elementary Physical Education

PURPOSE The objective of this study was to determine a pedometer steps per minute standard for quantifying the lesson time that first- and second-grade physical education students spent in moderate to vigorous physical activity (MVPA). METHODS The sample was divided into validation (N = 246) and cross-validation (N = 123) samples using the holdout technique. Using the criterion test model, steps per minute cut points were empirically and judgmentally determined. C-SOFIT systematic observation was the criterion instrument and pedometry was the predictor instrument. Data were collected from 45 physical education lessons implemented in six schools. The three-step analytic procedure of computing mastery/nonmastery outcome probabilities, phi coefficients, and error proportions was used to determine the optimal steps per minute cut point for quantifying 33.33% of the physical education lesson time engaged in MVPA within a 30 class. RESULTS Steps per minute was highly correlated with observation (r = 0.74-0.86, P < 0.0001). Five steps per minute scores that were accurate indicators of 33.33% of the class time engaged in MVPA in the validation sample were accurate indicators of steps per minute in the cross-validation sample. The optimal steps per minute cut point ranged from 60.00 to 63.00, which is equivalent to 1800-1890 steps in a 30-min physical education class. CONCLUSION Data supports the use of pedometry steps per minute values as an accurate indicator of MVPA. Pedometry demonstrates promise as a viable large-scale surveillance instrument for measuring MVPA in physical education.

Cardiorespiratory Fitness and Coronary Heart Disease Risk Factors The LDS Hospital Fitness Institute Cohort

BackgroundCardiorespiratory fitness is favorably associated with most modifiable coronary heart disease (CHD) risk factors. Findings are limited, however, by few data for women, persons with existing CHD, and low-risk populations. In the present study, we described cross-sectional associations between cardiorespiratory fitness and CHD risk factors in a large cohort of middle-aged men and women, of whom the majority were LDS Church members (Mormons), with and without existing CHD. Methods and ResultsComprehensive health examinations were performed on 3232 men (age 45.9±10.8 years) and 1128 women (age 43.8±12.8 years) between 1975 and 1997. Maximal treadmill exercise testing was used to categorize those with (12% of the men and 10% of the women) and those without CHD into age- and sex-specific cardiorespiratory fitness quintiles. After adjustments for age, body fat, smoking status, and family history of CHD, favorable associations were observed between fitness and most CHD risk factors among men and women, regardless of CHD status. ConclusionsThese data indicate that enhanced levels of cardiorespiratory fitness may confer resistance to elevations in CHD risk factors even in a low-risk sample of middle-aged men and women. Furthermore, these findings reinforce current public health recommendations that advocate increased national levels of physical activity and cardiorespiratory fitness for primary and secondary CHD prevention.

Exercise and Fitness for Persons with Disabilities

SummaryOver the past decade greater attention has been focused on the role of exercise and fitness for persons with disabilities. Increased involvement in exercise programmes, competitive sports and fitness activities has led to further inquiry into the broader concepts of performance, prevention of further deterioration of a given disability, maintenance for activities of daily living, and overall well-being. This paper reviews the literature on 3 categories of disabilities, mental retardation, mental illness and selected physical disabilities, in order to determine the role of exercise and fitness programmes in each. Despite problems in research design, sampling procedures, instrument validity, and delineation of fitness components, there is growing support for the premise that physical exercise has a role to play in breaking the debilitative cycle. Although the research indicates that physical activity can serve as a potential non-pharmacological adjunct therapy for persons with physical disabilities, there is still a need for well-controlled studies to quantify the individualisation of exercise programming.

Does Augmented Feedback from Pedometers Increase Adults' Walking Behavior?

This study investigated whether feedback from pedometers motivated adults to increase their walking behavior. Participants (n = 26) were enrolled in one of two 8-wk. “Walking for Fitness” classes. The study used a crossover design, such that Group 1 wore pedometers for the first 3 weeks (Feedback Condition) and sealed “disguised” pedometers for the last 3 weeks (No-feedback Condition). The order of feedback was reversed for Group 2. Analysis indicated that (a) neither group increased their walking behavior significantly over time and, (b) interactions between groups were not significant at Week 3 or 6, indicating that groups did not respond differently to feedback from the pedometers. If a motivational effect from pedometers exists, it may be small, dissipate before 3 wk., only work in combination with goal setting, or only motivate certain types of individuals.

Waist Circumference, Pedometer Placement, and Step-Counting Accuracy in Youth

This study examined whether differences in waist circumference (WC) and pedometer placement (anterior vs. midaxillary vs. posterior) affect the agreement between pedometer and observed steps during treadmill and self-paced walking. Participants included 19 pairs of youth (9–15 years old) who were matched for sex, race, and height and stratified by WC (high WC: HWC; low WC: LWC). Participants performed 3-min treadmill-walking trials at speeds of 59, 72, and 86 m·min-1 and a 400-m self-paced walking trial on level ground. Bland-Altman plots were used to assess the agreement between pedometer and observed steps of spring-levered pedometers by WC, pedometer placement, and walking speed. In the HWC group, the posterior pedometer placement consistently agreed most closely with observed steps at all treadmill speeds and during self-paced walking. In the LWC group, no single pedometer placement consistently agreed most closely with observed steps at all treadmill speeds and during self-paced walking. We conclude that a posterior pedometer placement improves step-count accuracy in most youth with an HWC at a range of walking speeds on level ground.

Repetitive Eccentric Strain at Long Muscle Length Evokes the Repeated Bout Effect

The repeated bout effect (RBE) is a phenomenon characterized by less delayed onset muscle soreness (DOMS) and torque deficit after the second of 2 separate eccentric exercise bouts. Previous investigators have reported that shifting of optimum angle after an initial bout of eccentric exercise mediates the RBE. We hypothesized that an RBE for elbow extensor exercise occurs after an initial bout performed at long (starting position of 508 to an end position of 1308) but not short (starting position of 08 to an end position of 808) muscle length because strain at long length evokes a shifting of the optimum angle to a longer length. Untrained women performed an initial bout at either long or short length (n = 9 per group) followed 1 week later by a repeated bout (RB) through the full ROM (0–1308). Extensor torque and optimum angle was evaluated before, immediately after, and 2 days after each bout. A mechanical transducer depressed on the triceps brachii quantified DOMS. Torque deficits were 3% and 7% after exercise at short vs. long length, respectively. Two days after the RB, torque deficit was 8% and 1% for those previously exercising at short vs. long length (group 3 bout, p < 0.05). Greater DOMS (N) was observed after exercise at long (16 ± 3) vs. short (23 ± 2) length; whereas greater DOMS occurred for the short-length (17 ± 2) vs. long (26 ± 3) group after the RB (group 3 bout, p < 0.05). Optimum angle shifted to a longer length after exercise at long (110 ± 48) vs. short (11 ± 38) length (group 3 bout, p < 0.05). After the RB, those exercising previously at short length experienced a shift of 115 ± 48 (main effect, p < 0.05). The findings of this study indicate that the repetitive strain at long but not short muscle length evokes both immediate and sustained shifts in optimum angle to longer lengths, and that this shifting mediates (r2 5 0.71) the RBE.

Cross-Validation of Aerobic Capacity Prediction Models in Adolescents

Cardiorespiratory endurance is a component of health-related fitness. FITNESSGRAM recommends the Progressive Aerobic Cardiovascular Endurance Run (PACER) or One mile Run/Walk (1MRW) to assess cardiorespiratory endurance by estimating VO2 Peak. No research has cross-validated prediction models from both PACER and 1MRW, including the New PACER Model and PACER-Mile Equivalent (PACER-MEQ) using current standards. The purpose of this study was to cross-validate prediction models from PACER and 1MRW against measured VO2 Peak in adolescents. Cardiorespiratory endurance data were collected on 90 adolescents aged 13-16 years (Mean = 14.7 ± 1.3 years; 32 girls, 52 boys) who completed the PACER and 1MRW in addition to a laboratory maximal treadmill test to measure VO2 Peak. Multiple correlations among various models with measured VO2 Peak were considered moderately strong (R = .74-0.78), and prediction error (RMSE) ranged from 5.95 ml·kg⁻¹,min⁻¹ to 8.27 ml·kg⁻¹.min⁻¹. Criterion-referenced agreement into FITNESSGRAMs Healthy Fitness Zones was considered fair-to-good among models (Kappa = 0.31-0.62; Agreement = 75.5-89.9%; F = 0.08-0.65). In conclusion, prediction models demonstrated moderately strong linear relationships with measured VO2 Peak, fair prediction error, and fair-to-good criterion referenced agreement with measured VO2 Peak into FITNESSGRAMs Healthy Fitness Zones.

Development of an aerobic capacity prediction model from one-mile run/walk performance in adolescents aged 13–16 years

Abstract A popular algorithm to predict VO2Peak from the one-mile run/walk test (1MRW) includes body mass index (BMI), which manifests practical issues in school settings. The purpose of this study was to develop an aerobic capacity model from 1MRW in adolescents independent of BMI. Cardiorespiratory endurance data were collected on 90 adolescents aged 13–16 years. The 1MRW was administered on an outside track and a laboratory VO2Peak test was conducted using a maximal treadmill protocol. Multiple linear regression was employed to develop the prediction model. Results yielded the following algorithm: VO2Peak = 7.34 × (1MRW speed in m s−1) + 0.23 × (age × sex) + 17.75. The New Model displayed a multiple correlation and prediction error of R = 0.81, standard error of the estimate = 4.78 ml kg−1·min−1, with measured VO2Peak and good criterion-referenced (CR) agreement into FITNESSGRAM’s Healthy Fitness Zone (Kappa = 0.62; percentage agreement = 84.4%; Φ = 0.62). The New Model was validated using k-fold cross-validation and showed homoscedastic residuals across the range of predicted scores. The omission of BMI did not compromise accuracy of the model. In conclusion, the New Model displayed good predictive accuracy and good CR agreement with measured VO2Peak in adolescents aged 13–16 years.

Addressing Health Disparities from Within the Community: Community-Based Participatory Research and Community Health Worker Policy Initiatives Using a Gender-Based Approach

BACKGROUND The Coalition for a Healthier Community for Utah Women and Girls (CHC-UWAG) focused on addressing obesity-related health disparities impacting Utah women of color using community-based participatory research, a gender-based approach, and culturally sensitive health promotion activities delivered through community health workers (CHWs). A randomized trial of low vs. high intensity wellness coaching by CHWs was initiated. During this process, numerous policy issues emerged and were tracked. We present a case study illustrating how we identified, tracked, and engaged with emerging policy initiatives. METHODS Between September 2011 and August 2017, policy initiatives addressing obesity-related disparities among Utah women and girls were identified, tracked in a shared document, and updated regularly. Policies were classified by level (organizational, local, and statewide) and by focus (healthy eating, active living, and promotion of community health workers). CHC-UWAG engagement with policy work was also documented and tracked. RESULTS Broad dissemination of study findings generated interest in the role of CHWs in addressing obesity. Partnering community-based organizations implemented policies focused on healthy eating and physical activity. Barriers to the broader use of CHWs in Utah were addressed in policy initiatives including the formation of a Utah Public Health Association Section for CHWs and a statewide CHW Coalition with involvement of CHC-UWAG members. CONCLUSIONS The regular solicitation of information about policy initiatives resulted in successful policy tracking and engagement in policy work. The utilization of a gender-based approach helped illuminate the impact of emerging policies on the health of women and girls.

Effect of a randomised 12-week resistance training programme on muscular strength, cross-sectional area and muscle quality in women having undergone Roux-en-Y gastric bypass

ABSTRACT The purpose of this study was to examine the effect of a 12-week resistance training programme on fat-free mass (FFM), muscle cross-sectional area, muscular strength and muscle quality in women who underwent Roux-en-Y gastric bypass surgery. Participants were 16 women (mean age = 44.9 ± 10.2 years) from bariatric surgical groups who were randomly assigned into either a control or an intervention group. Air displacement plethysmography measured FFM and magnetic resonance imaging measured quadriceps muscle cross-sectional area and whole thigh muscle cross-sectional area. Muscular strength and quality was assessed using an estimated 1-Repetition Maximum assessment. All measurements were collected twice, at baseline and at a 12-week follow-up. There were significantly greater improvements in leg press strength (mean differences = 55.4%, P < 0.001, Cohen’s d = 2.4), leg extension strength (mean differences = 18.0%, P = 0.014, Cohen’s d = 0.86) and leg press muscle quality (mean differences = 54.5%, P < 0.001, Cohen’s d = 1.9) in the intervention group compared to the control group following the resistance training programme. The resistance training intervention significantly improved muscular strength and quality; however, it did not illicit changes in FFM or muscle cross-sectional area in women who underwent Roux-en-Y gastric bypass surgery.