Mark G. Abel

Promoting Children's Health Through Physically Active Math Classes: A Pilot Study

School-based interventions are encouraged to support youth physical activity (PA). Classroom-based PA has been incorporated as one component of school wellness policies. The purpose of this pilot study is to examine the effects of integrating PA with mathematics content on math class and school day PA levels of elementary students. Participants include four teachers and 75 students. Five math classes are taught without PA integration (i.e., baseline) followed by 13 math classes that integrate PA. Students wear pedometers and accelerometers to track PA during math class and throughout the school day. Students perform significantly more PA on school days and in math classes during the intervention. In addition, students perform higher intensity (step min-1) PA during PA integration math classes compared with baseline math classes. Integrating PA into the classroom is an effective alternative approach to improving PA levels among youth and is an important component of school-based wellness policies.

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.

A comprehensive evaluation of motion sensor step-counting error

The purpose of this study was to conduct a comprehensive evaluation of the effect that walking speed, gender, leg length, motion sensor tilt angle, brand, and placement have on motion sensor step-counting error. Fifty-nine participants performed treadmill walking trials at 6 speeds while wearing 5 motion sensor brands placed on the anterior (Digiwalker, DW; Walk4Life, WFL; New Lifestyles, NL; Omron, OM), midaxillary (DW; WFL; NL; ActiGraph, AG), and posterior (DW, WFL, NL) aspects of the waistline. The anterior-placed NL and midaxillary-placed AG were the most accurate motion sensors. Motion sensor step-count error tended to decrease at faster walking speeds, with lesser tilt angles, and with an anterior waistline placement. Gender and leg length had no effect on motion sensor step-count error. We conclude that the NL and AG yielded the most accurate step counts at a range of walking speeds in individuals with different physical characteristics.

Evaluation of circuit-training intensity for firefighters.

Abel, MG, Mortara, AJ, and Pettitt, RW. Evaluation of circuit-training intensity for firefighters. J Strength Cond Res 25(10): 2895–2901, 2011—Firefighters are required to perform a variety of strenuous occupational tasks that require high levels of both aerobic and anaerobic fitness. Thus, it is critical that firefighters train at an appropriate intensity to develop adequate levels of aerobic and anaerobic fitness. Circuit training is a unique training method that stresses both energy systems and therefore may be a viable training method to enhance firefighter preparedness. Thus, the purpose of this study was to compare the aerobic and anaerobic intensities of a circuit-based workout to physiological data previously reported on firefighters performing fire suppression and rescue tasks. Twenty career firefighters performed a workout that included 2 rotations of 12 exercises that stressed all major muscle groups. Heart rate was recorded at the completion of each exercise. Blood lactate was measured before and approximately 5 minutes after the workout. The workout heart rate and post–workout blood lactate responses were statistically compared to data reported on firefighters performing fire suppression and rescue tasks. The mean circuit-training heart rate was similar to previously reported heart rate responses from firefighters performing simulated smoke-diving tasks (79 ± 5 vs. 79 ± 6% maximum heart rate [HRmax], p = 0.741), but lower than previously reported heart rate responses from firefighters performing fire suppression tasks (79 ± 5 vs. 88 ± 6% HRmax, p < 0.001). The workout produced a similar peak blood lactate compared to that when performing firefighting tasks (12 ± 3 vs. 13 ± 3 mmol·L−1, p = 0.084). In general, the circuit-based workout produced a lower cardiovascular stress but a similar anaerobic stress as compared to performing firefighting tasks. Therefore, firefighters should supplement low-intensity circuit-training programs with high-intensity cardiovascular and resistance training (e.g., ≥85% 1-repetition maximum) exercises to adequately prepare for the variable physical demands of firefighting.

The effect of a novel tactical training program on physical fitness and occupational performance in firefighters

Abstract Pawlak, R, Clasey, JL, Palmer, T, Symons, TB, and Abel, MG. The effect of a novel tactical training program on physical fitness and occupational performance in firefighters. J Strength Cond Res 29(3): 578–588, 2015—Structural firefighting is a dangerous and physically demanding profession. Thus, it is critical that firefighters exercise regularly to maintain optimal physical fitness levels. However, little is known about optimal training methods for firefighters, and exercise equipment is often not available to on-duty firefighters. Therefore, the purpose of this study was to determine the effect of a novel supervised on-duty physical training program on the physical fitness and occupational performance of structural firefighters. Twenty professional male firefighters were divided into a supervised exercise group (SEG; n = 11) and a control group (CG; n = 9). The SEG participated in a 12-week circuit training intervention. The SEG exercised for 1 hour on 2 d·wk−1. At baseline and after the intervention, subjects performed a battery of physical fitness tests and a simulated fire ground test (SFGT). At baseline, there were no significant differences (p = 0.822) in the completion rate of the SFGT in the SEG (82%) vs. the CG (78%). After the intervention, a significantly greater proportion of the firefighters in the SEG completed the SFGT compared with the CG (SEG = 100% vs. CG = 56%; p < 0.013). In addition, the SEG demonstrated significant improvements in body mass, fat mass, and body mass index (p ⩽ 0.05). The findings of this study indicate that training with firefighter equipment improved occupational performance and anthropometric outcomes in incumbent firefighters. Furthermore, implementing a supervised exercise program using firefighter equipment can be done so in a safe and feasible manner.

Arterial hemodynamics are impaired at rest and following acute exercise in overweight young men

Higher body mass index (BMI) is associated with greater cardiovascular disease (CVD) risk, in part due to aortic stiffening assessed by carotid-femoral pulse wave velocity (cfPWV). Importantly, greater cardiorespiratory fitness (CRF; VO2peak) decreases CVD risk, and is associated with reductions in aortic stiffness. We tested the hypothesis that young adult overweight (OW, n=17) compared with healthy-weight (HW, n=17) men will have greater resting aortic stiffness, reduced CRF and an impaired post-exercise hemodynamic response. Resting cfPWV was greater in OW versus HW individuals (5.81 ± 0.13 vs 4.81 ± 0.12 m/sec, p<0.05). Relative CRF (VO2peak; mL/kg/min) was lower in OW compared with HW individuals (49.4 ± 1.3 vs 57.6 ± 1.0 mL/kg/min, p<0.05), and was inversely related with cfPWV (p<0.05). However, CRF as absolute VO2peak (L/min) was not different between groups and there was no relation between cfPWV and absolute VO2peak (L/min), indicating reduced relative CRF in OW men is due to greater body mass. Following the maximal treadmill exercise test, cfPWV was greater in OW compared with HW subjects from rest to 60 minutes post-exercise (p<0.05). Compared with HW, OW individuals had higher systolic blood pressure (main effect, p<0.05) and diastolic blood pressure was selectively increased for up to 60 minutes following exercise (p<0.05). Overweight individuals had an attenuated post-exercise decrease in mean arterial pressure (p<0.05). Collectively, these results indicate that young, apparently healthy, OW men have greater resting aortic stiffening and an impaired post-exercise hemodynamic response.

The effects of using stationary bicycle desks in classrooms on adolescents’ physical activity

ABSTRACT The high level of overweight and obesity in children and adolescents has been termed a public health crisis and is associated with low levels of physical activity (PA). Experts recommend that youth engage in 60 minutes or more of moderate to vigorous PA per day, yet two-thirds of adolescents do not obtain this goal. Schools have been identified as locations in which PA promotion should occur, but there are limited opportunities for adolescents to enhance their PA during school hours. The present study used stationary bicycle desks (FitDesk) in a secondary school to investigate whether these desks enhanced student PA over an academic year. Results indicated that the students on the bicycle desks spent less relative time in sedentary activity, spent more time in moderate-to-vigorous physical activity (MVPA), and improved each of the PA outcomes compared to the control group from Assessment Period 1 to Period 2. Students and teachers noted both advantages and limitations of using the desks during the school day but overall were enthusiastic about the use of FitDesks in classrooms. Implications for enhancing activity during the school day for occupational therapists and limitations of using the stationary bike desks are discussed.

Exercise Program Design for Structural Firefighters

ABSTRACT STRUCTURAL FIREFIGHTING IS A PHYSICALLY DEMANDING AND HAZARDOUS PROFESSION THAT REQUIRES SUFFICIENT LEVELS OF PHYSICAL FITNESS TO ENHANCE OCCUPATIONAL PREPAREDNESS, SAFETY, AND HEALTH. A COMPREHENSIVE EXERCISE PROGRAM SHOULD BE IMPLEMENTED TO ACHIEVE THE REQUISITE PHYSICAL FITNESS. A NEEDS ANALYSIS IS PRESENTED TO ENSURE THAT AN EXERCISE PROGRAM ADDRESSES THE PHYSIOLOGICAL AND BIOMECHANICAL DEMANDS OF OCCUPATIONAL TASKS. IDENTIFYING SPECIFIC NEEDS WILL PROMOTE ENHANCED WORK EFFICIENCY AND A DECREASED RISK OF FIRE GROUND INJURIES AND CHRONIC DISEASE. IN ADDITION, THE FIREFIGHTING OCCUPATION PRESENTS INHERENT CHALLENGES TO DEVELOPING AN APPROPRIATE TRAINING PROGRAM. PROGRAMMATIC TRAINING STRATEGIES ARE PRESENTED TO OVERCOME THESE CHALLENGES.

Development of a System for Observing Dance Activities in the Classroom Environment (SODANCE).

Abstract This study sought to develop a system for observing dance activities in the classroom environment (SODANCE) based on the system for observing fitness instructional time (SOFIT). SODANCE utilizes direct observation to quantify the physical activity intensity of dance activities. Female students aged 11–17 years participated in an activity protocol of SOFIT and common dance activities to identify appropriate coding categories. Each student wore a heart rate monitor and accelerometer while performing the following activities: lying, sitting, standing, walking, running, single-leg balances, leg swings, pirouettes, and leaps. Ultimately, heart rate reserve output was determined to be the best assessment, followed by accelerometry-based vector magnitude output, and expert opinion. Chi squared tests were used to determine if there were significant differences in the proportion of subjects whose heart rate reserve data classified the activity as light vs. moderate vs. vigorous. In conclusion, the dance activities were coded as follows: single-leg balances = 4, leg swings = 4, pirouettes = 5, and leaps = 5. The developed SODANCE instrument may be used by researchers and practitioners to assess physical activity intensity during dance classes in the public schools.

Development of 1RM Prediction Equations for Bench Press in Moderately Trained Men.

Abstract Macht, JW, Abel, MG, Mullineaux, DR, and Yates, JW. Development of 1RM prediction equations for bench press in moderately trained men. J Strength Cond Res 30(10): 2901–2906, 2016—There are a variety of established 1 repetition maximum (1RM) prediction equations, however, very few prediction equations use anthropometric characteristics exclusively or in part, to estimate 1RM strength. Therefore, the purpose of this study was to develop an original 1RM prediction equation for bench press using anthropometric and performance characteristics in moderately trained male subjects. Sixty male subjects (21.2 ± 2.4 years) completed a 1RM bench press and were randomly assigned a load to complete as many repetitions as possible. In addition, body composition, upper-body anthropometric characteristics, and handgrip strength were assessed. Regression analysis was used to develop a performance-based 1RM prediction equation: 1RM = 1.20 repetition weight + 2.19 repetitions to fatigue − 0.56 biacromial width (cm) + 9.6 (R 2 = 0.99, standard error of estimate [SEE] = 3.5 kg). Regression analysis to develop a nonperformance-based 1RM prediction equation yielded: 1RM (kg) = 0.997 cross-sectional area (CSA) (cm2) + 0.401 chest circumference (cm) − 0.385%fat − 0.185 arm length (cm) + 36.7 (R 2 = 0.81, SEE = 13.0 kg). The performance prediction equations developed in this study had high validity coefficients, minimal mean bias, and small limits of agreement. The anthropometric equations had moderately high validity coefficient but larger limits of agreement. The practical applications of this study indicate that the inclusion of anthropometric characteristics and performance variables produce a valid prediction equation for 1RM strength. In addition, the CSA of the arm uses a simple nonperformance method of estimating the lifters 1RM. This information may be used to predict the starting load for a lifter performing a 1RM prediction protocol or a 1RM testing protocol.