Marcie B. Beckett’s scientific contributions

This study was performed to determine the effect of changes in skin blood flow (SBF) on bioelectrical resistance (RES). Twenty-three men had their left hand repeatedly immersed (1 min) and removed from water (3 min) for a total of 12 min in order to manipulate SBF in the contralateral (right) limbs where RES electrodes were located. Tests were completed at three water temperatures (5, 15, and 350C) in constant ambient air temperature (25 +/- 1 deg C). SBF was monitored on the middle finger of the right hand using a laser-Doppler flowmeter, and skin temperature on the dorsal right hand (Th) and foot (Tf). Time series analysis revealed cyclic SBF and RES responses were inversely correlated at all water temperatures (r = -0. 38 to -0. 64; p < .05) . T. and Tf were not correlated with SBF for any test. During hand immersion in 5, 15, and 350C water, SBF decreased by 36, 20, and 4%, respectively, while RES increased by 3.5, 2.0, and 0.7 ohms, respectively. When incorporated into existing bioimpedance (BIA) prediction equations, the largest RES difference observed (3. 5 ohms) translated into a difference of 0.4% body fat and 0.4 L body water. Changes in SBF of the magnitude observed in this study appear to have a relatively small impact on BIA prediction of body water and composition. Bioelectrical impedance, Skin blood flow, Body composition, Skin temperature, Laser-Doppler flowmetry.

Assessed the role of psychological variables (mood, physical estimation and attraction, self-concept, and personality) in predicting physical performance and fitness in 64 male and 38 female active-duty US Navy personnel. Ss performed physical performance and fitness tasks and completed standardized questionnaires. Results were analyzed by canonical correlation and multiple regression techniques. Men and women differed significantly on measures of size, body fat, and physical capacity. Findings indicate that questionnaire measures, most notably Attraction, Estimation, and Physical Self-Concept scores, can be used to predict both performance and fitness. There were no differences between men and women in significance of primary questionnaire measures to predict performance or fitness, with Attraction, Estimation, and Physical Self-Concept scores being the best predictors among all questionnaire measures in both gender groups. (PsycINFO Database Record (c) 2014 APA, all rights reserved)

Candidates for U.S. Navy Special Warfare Sea Air Land (SEAL) teams undergo vigorous training at Basic Underwater Demolition/SEAL (BUD/S) school. Recently, some question has arisen as to whether BUD/S graduates are adequately prepared to become active SEAL team members (SEALs). This study was undertaken to compare BUD/S graduates with SEALs with respect to their physical condition and capacities. Thirty-nine BUD/S graduates and 48 SEALs were characterized in terms of physical fitness, physique and cold pressor response. BUD/S graduates were found to be leaner than SEALs, to have slightly less muscle strength and anaerobic power, but greater muscle endurance and aerobic capacity. Both groups had similar responses to a cold pressor test. These differences undoubtedly reflect differences between the training and operational environments, and some consideration must be given to whether the training program needs to be modified to change physical fitness outcomes. It should be recognized, however, that these differences in physical fitness are relatively small, and BUD/S graduates appear sufficiently prepared to join the ranks of operational SEALs.

The purpose of the present study was to assess the role of psychological variables (e.g., mood scales, physical estimation and attraction, physical self-concept, and personality scales) in predicting physical performance and fitness measures in a sample of military volunteers. Subjects were 102 active duty U. S. Navy personnel, 64 males and 38 females. Subjects performed a number of physical performance and fitness tasks (including 1.5-mile run, carrying task, and incremental treadmill task), and completed a battery of standardized questionnaires. Results were analyzed by multiple regression technique. The primary findings were: (a) questionnaire measures, most notably the Attraction score from the Physical Estimation and Attraction Scale, can be used to predict performance and fitness measures in an active duty Navy sample; (b) while fitness measures are clearly superior to questionnaire measures in predicting physical performance, questionnaire measures, again most notably the Attraction score, can be used to enhance the prediction equation over fitness measures alone; (c) there were only minimal differences between males and females in significance of questionnaire measures to predict performance or fitness.

Through the Physical Readiness Test (PRT), the Navy assesses the physical fitness and body composition of its members. Those fitness attributes which contribute to optimal Navy job performance have not yet been fully identified. The purpose of this study was to determine the extent to which performance of simulated general shipboard work can be predicted by measures of physical capacity. Three tasks representative of general shipboard work were developed - a long duration carry and two maximal box lifting tests. These tasks, as well as, PRT items (including lean body mass LBM from body circumference and weight), other field fitness measures, and Incremental Lift Machine (ILM) tests were performed by 102 Navy men and women. Substitution of broad jump score for LBM offers a small improvement in task prediction. ILM scores offer lift capacity prediction comparable to that obtained from PRT and broad jump scores. LBM, broad jump and ILM scores are all strong indicators of overall body strength. If these prediction methods are to be implemented as screening or selection tools, critical lifting and carrying task parameters for Navy jobs must be defined. In addition, further research is needed to cross-validate results obtained in this study and to expand prediction application.

In October 1981, OPNAVINST 6110.1B was promulgated establishing the percentage of body weight contributed by fat mass (%BF) as the basis for weight control decisions. Tables based upon the work of Wright, et al. allowing prediction of %BF from neck, biceps, forearm, abdomen and thigh circumferences were accepted for use on an interim basis. This report covers validation of the equation of Wright and his co-workers, as well as development and cross- validation of a new equation which offers improved prediction of %BF for U.S. Navy female personnel. Anthropometric measures consisting of 8 skinfold thicknesses, 11 body circumferences, height, and body weight were made of 214 female U.S. Navy personnel aged 18-44 years (mean age - 26.5 years). In addition, each participant had her body density and %BF determined by underwater weighing. Validity of the Wright equation was assessed by correlation between predicted and measured %BF. The correlation coefficient - 0.80 (std. err. meas. = 4.19 %BF). Errors in prediction near the Navy minimum standard of 30% BF, dictated development of a new equation. Factor analysis of the anthropometric variables indicated a suitable equation could be developed using circumferences and height as predictors. An equation was developed using forward, stepwise multiple regression of logarithmic transforms of circumferences and height as predictors of body density determined from underwater weighing. The final equation was: Body Density = -0.350 x log (ABDOMEN I + HIP - NECK) + 0.221 X log (HEIGHT) + 1.296. All measurements are expressed in centimeters. The multiple correlation coefficient for this equation was 0.85.