Impact of body weight on performance of a weight-supported motor fitness test in men.

The impact of body weight on test scores is a common issue in applied measurement. Dimensional analysis suggests that heavier participants are disadvantaged in weight-supported tasks. The purpose of this study was to evaluate the impact of body weight on performance scores for a military obstacle course. Three cohorts of male participants completed the Indoor Obstacle Course Test (IOCT). In cohort 1 (N = 2,191), height and weight were measured. In cohort 2 (N = 134), skinfold measurements were also performed. In cohort 3 (N = 44), all aforementioned measurements were performed, as well as upper- and lower-body tests for aerobic power, anaerobic power, muscular strength, and muscular endurance. The R2 between IOCT scores and body weight was 0.06 and that between IOCT scores and percentage of body fat was 0.08. All cohort analyses suggested that, for male subjects, body weight had only a small impact on the performance score distribution and the IOCT is fit for purpose as a fair repeatable system for assessment of physical performance.

Effects of heavy load carriage during constant-speed, simulated, road marching.

Load carriage is a key element in dismounted military operations. Load carriage requirements in the field regularly exceed 50% of lean body mass (LBM) and have only rarely been studied. Therefore, our purpose was to determine the metabolic and motivational effects of heavy loads (30-70% LBM) during constant-rate "road" marching on a treadmill. Ten healthy male Army officers carried loads of 30%, 50%, and 70% LBM in an all-purpose, lightweight, individual, carrying equipment pack for 30 minutes, at a speed of 6 km/h. Oxygen consumption (VO2), ventilation, heart rate (HR), respiratory exchange ratio, rating of perceived exertion (RPE), and Self-Motivation Inventory scores were recorded at each trial. Significant increases were observed for VO2, ventilation, and HR between the trials. RPE significantly increased for the 70% LBM trial, compared with the 30% and 50% trials. No significant differences were seen in respiratory exchange ratio or Self-Motivation Inventory scores. Increasingly heavy loads carried in a rucksack resulted in increased VO2, RPE, and HR; therefore, increasing the load that a soldier is required to carry may negatively affect road march performance.

Metabolic effects of soldier performance on a simulated graded road march while wearing two functionally equivalent military ensembles.

OBJECTIVES: The purpose of this study was to examine metabolic effects of soldier performance on a simulated road march, comparing two functionally equivalent military ensembles (FEMEs) with changing gradation of marching, and to create prediction equations addressing workload with different loads and treadmill grades. METHODS: Fourteen male military subjects were tested while wearing two different FEMEs on a graded (0%, 5%, or 10%), 3.5 miles/h, road march for 30 minutes. Data collected included oxygen uptake (VO2), carbon dioxide output, ventilation, respiratory exchange ratio, and heart rate (HR). RESULTS: No significant differences were found between the two FEMEs in each graded condition. Combining ensemble data, significant differences occurred in all conditions, comparing all grades. A 10% graded road march (3.5 miles/h, approximately 27-kg load) represented 61% to 90% of maximal values. For treadmill grades of <10%, VO2 and HR were modeled as follows (adjusted R2 = 0.89 [VO2] and 0.82 [HR]): VO2 (mL/kg per minute) = 10 + [2 - grade (%)] + [0.2 - load (% of body mass)]; HR (beats per minute) = 90 + [6 . grade (%)] + [0.7 - load (% of body mass)]. CONCLUSIONS: Three factors, namely, elevation grade, equipment weight (load), and overall subject physical abilities, were significant for overall metabolic demand during a simulated graded road march and might affect field performance.

Body mass penalties in the physical fitness tests of the Army, Air Force, and Navy.

Recent research has empirically documented a consistent penalty against heavier service members for events identical or similar to those in the physical fitness tests of the Army, Air Force, and Navy. These penalties, which are not related to body fatness, are based on biological scaling models and have a physiological basis. Using hypothetical cases, we quantified the penalties for men, with body mass of 60 vs. 90 kg, and women, 45 vs. 75 kg, to be 15% to 20% for the fitness tests of these three services. Such penalties alone can adversely affect awards and promotions for heavier service members. To deal equitably with these penalties in a practical manner, we offer two recommendations, i.e., (1) implementation of revised fitness tests with balanced events, in which the penalties of one event for heavier service members are balanced by an equal and opposite bias against lighter service members, or (2) development of correction factors that can be multiplied by raw scores to yield adjusted scores free of body mass bias.

Improvement in sit-up performance associated with 2 different training regimens.

STUDY DESIGN: Factorial experimental design. OBJECTIVE: To compare the outcomes of 2 different abdominal muscular fitness training regimens on sit-up performance across sex and abdominal muscular fitness level. BACKGROUND: Researchers suggest that the curl-up, when compared to the sit-up, optimizes the challenge to the abdominal muscles while minimizing shear and compressive forces on the lumbar spine. Although researchers have compared curl-ups and sit-ups in many ways, a comparison of sit-up performance after training programs involving curl-ups and sit-ups has not been investigated. METHODS AND MEASURES: One hundred two active, healthy, college-aged subjects participated in this study. After stratification based upon maximal 2-minute sit-up performance during the orientation session, subjects were randomly assigned to either a training group using curl-up exercise, a training group using sit-up exercise, or a control group. Maximal 2-minute sit-up test performance was measured before and after a 6-week training program. Data were analyzed utilizing an ANOVA model. Significant interactions or main effects were analyzed utilizing Tukey's Honestly Significant Difference Test. Level of significance for all testing was at alpha = 0.05. RESULTS: The sit-up training group improved significantly (P < 0.05). No significant difference in sit-up performance was noted for the curl-up or control groups after the 6-week training program. No statistically significant difference in improvement was noted between sex of subject and level of abdominal muscular fitness of subject. CONCLUSIONS: Short-term sit-up training with the Modified Kersey Method in this population significantly improved a maximum 2-minute sit-up test performance. Curl-up training utilizing the same method did not result in improvement in the number of sit-ups performed in 2 minutes. Specificity of training provides the primary explanation for our findings.

Creation of a criterion-referenced Military Optimal Performance Challenge.

PURPOSE: To compare an empirical, Army doctrine-based (endurance, strength, mobility, military relevant tasks), criterion-referenced, body mass (BM) unbiased Military Optimal Performance Challenge (MOPC) to the Army's Physical Fitness Test (APFT) and thus assisting commanders to determine military readiness. METHODS: Militarily-relevant physical assessments were combined to create a composite MOPC score. The MOPC and APFT were administered to 20 male, military subjects during a 2-week period. Data collection included 3-Mile Run, Mobility Test, Upper/Lower Body Strength/Endurance, Simulated Casualty Evacuation Test. The APFT was administered through Army guidelines before MOPC data collection. RESULTS: The APFT was influenced by BM, lean body mass (LBM) (r = -0.44; r(2) = 0.20; p = 0.04), whereas MOPC was less impacted (r = 0.21; r(2) = 0.04; p = 0.32). Eight subjects, as viewed by %APFT, are "fit for duty" (80.6%); however, all eight subjects' mean score as %MOPC was <50%. CONCLUSIONS: The MOPC offers a robust approach to military readiness and is free of the confounding influence of BM. The MOPC is a unique assessment requiring a multitude of abilities to garner success and may assist in training for functional combat performance skills demanding high work capacities.