Leg fat-free mass and inter-limb leg fat-free mass asymmetry comparisons between bioelectrical impedance analysis and dual-energy X-ray absorptiometry in male career firefighters.

The purpose of this study was to compare dominant and non-dominant leg fat-free mass (FFM) estimations and inter-limb leg FFM asymmetry detection between multi-frequency bioelectrical impedance analysis (MF-BIA) and dual-energy X-ray absorptiometry (DXA) in career firefighters. Sixty-one male career firefighters (age = 31.9 ± 7.

Work-Related Fatigue: Relationship Between Perceived and Performance Fatigability in Career Firefighters.

Objective: The purpose of this study was to (1) examine the relationship between perceived work-related fatigue and performance fatigability, and (2) assess the impact of percent body fat (%BF) on perceived fatigue constructs in career firefighters.

Methods: Thirty-nine career firefighters completed body composition testing, the Occupational Fatigue Exhaustion Recovery (OFER15) scale assessing three subscales of work-related fatigue (acute fatigue, chronic fatigue, and inter-shift recovery), and maximal leg extensor isometric strength testing prior to and following an isotonic fatiguing protocol.

Results: Performance fatigability was not associated with any of the OFER15 perceived work-related fatigue variables ( P ≥ 0.

The impact of inter-limb leg lean tissue mass asymmetry on stair climb performance in career firefighters.

The purpose of this study was to examine the influence of inter-limb leg lean tissue mass (LTM) asymmetry on stair climb (SC) performance in firefighters. Forty-one career firefighters (age = 32.3 ± 8.

The feasibility of workload monitoring among law enforcement officers: A multi-methodological approach.

This study examined the feasibility of workload monitoring to assess internal workload in law enforcement officers (LEO) using a multi-methodological approach. Fifty front-line LEO completed workload surveys on workdays for eight weeks. Retention and adherence were assessed across the survey period.

Longitudinal Changes in Quadriceps Morphology over the First 3 Months after Anterior Cruciate Ligament Reconstruction.

Purpose: Neuromuscular deficits and atrophy after anterior cruciate ligament reconstruction (ACLR) may be accompanied by changes in muscle composition and poor quadriceps muscle quality (QMQ). Quadriceps atrophy occurs after ACLR but improves within the first three postoperative months, yet this hypertrophy could be attributable to increases in noncontractile tissue (i.e.

Impact of Age on the Affective Responses Following Worksite Resistance Exercise in Career Firefighters.

Introduction: The purpose of this study was to examine the impact of age on the affective responses (attitude, feelings, self-efficacy, intention, enjoyment, and fondness) after a worksite circuit-style resistance exercise routine in career firefighters.

Methods: Nineteen young (25.5 ± 3.

Validity of total body water measured by multi-frequency bioelectrical impedance devices in a multi-ethnic sample.

Background & Aims: Total body water (TBW) is the largest component of fat free mass and therefore is commonly used in multi-compartment body composition models and as a stand-alone method to assess body composition. Previous literature has not validated bioelectrical impedance spectroscopy device estimates of TBW in racial and ethnic minority populations; previous studies have focused on bioelectrical impedance analysis devices that rely on proprietary algorithms and participant characteristics for accuracy. The purpose of this study was to assess the validity of two bioelectrical impedance spectroscopy devices for measures of TBW compared to a deuterium dilution criterion in a multi-ethnic sample.

Test-Retest Reliability and Minimum Difference Values of a Novel and Portable Upright Row Strength Assessment in Probation Officers.

Upper body (UB) strength is important for occupational tasks and injury prevention in law enforcement officers (LEOs). Portable, reliable, and cost-effective assessments are needed to examine UB strength among LEOs in field settings. The purpose of this study was to examine the test-retest reliability and minimum difference (MD) values of a novel and portable isometric upright row assessment in probation officers.

The Time Course of Health, Fitness, and Occupational Performance Changes in Recruits across a Fire Academy.

Purpose: The purpose of this study was to examine the time course of health, fitness, and occupational performance changes in firefighter recruits across a fire academy.

Methods: Nineteen recruits (24.9 ± 4.

Differences in strength, leg lean mass, and lifestyle factors between premenopausal and perimenopausal women.

Background: Menopausal changes coupled with age-related reductions in muscle strength can impact functionality.

Aim: To evaluate the differences in muscle strength, dominant leg lean mass (DLM ), relative protein intake (r_PRO) and physical activity (PA) between premenopausal (PRE) and perimenopausal (PERI) women.

Methods: Twenty-four PRE- (age = 39.

Examining the Usability of Workload Monitoring in Firefighter Recruits.

Objective: Although workload monitoring is commonly used in athletic settings to mitigate injury risk, we are unaware of previous studies examining its feasibility among firefighters.

Methods: Nineteen firefighter recruits completed a short online workload survey at the end of each training day (Monday-Friday) for 26 weeks during the academy. A modified System Usability Scale was provided at midtesting (3 months into the academy) and posttesting (end of the academy).

Metabolic effects of menopause: a cross-sectional characterization of body composition and exercise metabolism.

Objectives: To evaluate body composition, fat distribution, and metabolism at rest and during exercise in premenopausal, perimenopausal, and postmenopausal women.

Methods: This cross-sectional study in 72 women ages 35 to 60 years evaluated body composition via a fourcompartment model, fat distribution using dual-energy x-ray absorptiometry-derived android to gynoid ratio, metabolic measures via indirect calorimetry, and lifestyle factors using surveys. One-way analyses of variance and one-way analyses of covariance covaried for age and hormone levels (estrogen and progesterone) were used to compare groups.

Segmental bioelectrical impedance spectroscopy: A novel field assessment of muscle size and quality in normal weight and obese older men.

The purpose of this study was to determine if segmental bioelectrical impedance spectroscopy characteristic frequency (f) and phase angle (P) were reflective of differences in quadriceps muscle size and quality, respectively, in normal weight and obese older men, and to assess the impact of hydration status on these measurements. Forty-one healthy older men volunteered for this study and were recruited by age (65-74 years) and two body mass index groups: normal weight and obese. Participants visited the laboratory on one occasion where they underwent a hydration status assessment via urine specific gravity, a percent body fat assessment via dual-energy X-ray absorptiometry, a segmental bioelectrical impedance spectroscopy thigh assessment to determine f and P, and resting ultrasonography to assess superficial quadriceps cross-sectional area and echo intensity as a proxy for muscle quality.

The validation of contemporary body composition methods in various races and ethnicities.

Few investigations have evaluated the validity of current body composition technology among racially and ethnically diverse populations. This study assessed the validity of common body composition methods in a multi-ethnic sample stratified by race and ethnicity. One hundred and ten individuals (55 % female, age: 26·5 (sd 6·9) years) identifying as Asian, African American/Black, Caucasian/White, Hispanic, Multi-racial and Native American were enrolled.

The impact of repeated bouts of shiftwork on rapid strength and reaction time in career firefighters.

The purpose of this study was to examine the influence of repeated bouts of shiftwork on lower extremity maximal and rapid strength and reaction time in career firefighters. Thirty-five firefighters (3 females; 34.3 ± 9.

Factors Associated with the Willingness to Perform a Physical Employment Standard in Probation Officers.

Purpose: This study examined worker characteristics and behaviors and the perceived importance of job-related tasks associated with the willingness to perform a proposed probation officer physical ability test (PROPAT).

Methods: North Carolina probation officers (N = 1213, 46.2% female, 39.

Metabolic effects of high-intensity interval training and essential amino acids.

High-intensity interval training (HIIT) promotes positive cardiometabolic and body composition changes. Essential amino acids (EAA) may support changes associated with HIIT, but evaluation of potential synergistic effects is lacking. The purpose of this study was to compare independent and combined effects of HIIT and EAA on total body composition and metabolism in men and women considered overweight/obese; an exploratory aim was to evaluate the modulatory effects of sex.

Neuromuscular determinants of simulated occupational performance in career firefighters.

Purpose: Although firefighters are required to perform various high-intensity critically essential tasks, the influence of neuromuscular function on firefighter occupational performance is unclear. The primary aim of the current study was to identify the key neuromuscular determinants of stair climb (SC) performance in firefighters.

Methods: Leg extension isometric peak torque (PT), peak power (PP), torque steadiness at 10% (Steadiness) and 50% (Steadiness) of PT, fatigability following 30 repeated isotonic concentric contractions at 40% of PT, percent body fat (%BF), and a weighted and timed SC task were examined in 41 (age: 32.

Acute feeding has minimal effect on the validity of body composition and metabolic measures: dual-energy X-ray absorptiometry and a multi-compartment model.

Understanding the effects of acute feeding on body composition and metabolic measures is essential to the translational component and practical application of measurement and clinical use. To investigate the influence of acute feeding on the validity of dual-energy X-ray absorptiometry (DXA), a four-compartment model (4C) and indirect calorimetry metabolic outcomes, thirty-nine healthy young adults ( 19 females; age: 21·8 (sd 3·1) years, weight; 71·5 (sd 10·0) kg) participated in a randomised cross-over study. Subjects were provided one of four randomised meals on separate occasions (high carbohydrate, high protein, ad libitum or fasted baseline) prior to body composition and metabolic assessments.

The influence of age on the recovery from worksite resistance exercise in career firefighters.

Unlabelled: Resistance exercise is an important strategy to reduce injuries and improve performance in the fire service. However, given the large age range of firefighters, it is important to determine if age influences their recovery following an acute bout of resistance exercise.

Purpose: To examine the changes in indirect markers of muscle damage in young and older firefighters following a feasible worksite resistance exercise routine.

Validity of Body-Composition Methods across Racial and Ethnic Populations.

Multi-compartment body-composition models that divide the body into its multiple constituents are the criterion method for measuring body fat percentage, fat mass, and fat-free mass. However, 2- and 3-compartment body-composition devices such as air displacement plethysmography (ADP), DXA, and bioelectrical impedance devices [bioelectrical impedance analysis (BIA)] are more commonly used. Accurate measures depend on several assumptions, including constant hydration, body proportion, fat-free body density, and population characteristics.

Measuring muscle quality: associations between echo intensity and normalized strength and power.

. Muscle quality has received considerable attention within the literature due to its influence on health and performance. However, it has been assessed by various measures (e.

High-intensity interval training and essential amino acid supplementation: Effects on muscle characteristics and whole-body protein turnover.

The purpose of this study was to compare the independent and combined effects of high-intensity interval training (HIIT) and essential amino acids (EAA) on lean mass, muscle characteristics of the quadriceps, and 24-hr whole-body protein turnover (WBPT) in overweight and obese adults. An exploratory aim was to evaluate potential modulatory effects of sex. Sixty-six adults (50% female; Age: 36.

An exploratory study of the effects of strenuous exercise on markers of coagulation activation, circulating microparticles, and inflammation in sickle cell trait.

This exploratory study evaluated the effect of intense exercise on biomarkers of inflammation and coagulation activation in subjects with and without sickle cell trait (SCT). Fifteen healthy African American men (18-35 years, 5 SCT, 10 control) completed a strenuous exercise protocol. Microparticle-associated prothrombinase and tissue factor activities, as well as soluble VCAM, total white cell and monocyte count increased transiently in all subjects following exercise.

Influence of Baseball Training Load on Clinical Reach Tests and Grip Strength in Collegiate Baseball Players.

Context: A baseball-specific training load may influence strength or glenohumeral range of motion, which are related to baseball injuries. Glenohumeral reach tests and grip strength are clinical assessments of shoulder range of motion and upper extremity strength, respectively.

Objective: To examine changes in glenohumeral reach test performance and grip strength between dominant and nondominant limbs and high, moderate, and low baseball-specific training-load groups.