RESUMO
Fifteen male soldiers performed six maximal-effort, 20-km road marchers. They carried load masses of 34, 48, and 61 kg, using a standard military backpack with frame or an experimental doublepack. March times decreased as mass increased and were faster with the standard pack than with the double-pack. The doublepack resulted in less low back discomfort and a lower incidence of blisters at the highest load, but also resulted in more discomfort in the neck and hips. Neither load mass nor pack type affected soldiers' marksmanship ability, grenade throw accuracy, or cognitive ability. The maximal-effort march itself affected the marksmanship tasks by increasing the post-march vertical shot group dispersion. The concept of distributing the load mass more evenly around the center of mass of the body has both positive and negative aspects and warrants further investigation.
Assuntos
Militares , Análise e Desempenho de Tarefas , Caminhada , Suporte de Carga , Vesícula/etiologia , Cognição/fisiologia , Equipamentos e Provisões , Dermatoses do Pé/etiologia , Frequência Cardíaca , Humanos , Masculino , Militares/psicologia , Dor/etiologia , Dor/fisiopatologia , Estados Unidos , Caminhada/lesões , Caminhada/fisiologiaRESUMO
This study was conducted to determine the effects on manual dexterity of the thickness of handcovering. Twelve men were timed as they performed five dexterity tests while barehanded and while wearing each of three thicknesses of chemical protective gloves, 0.18 mm, 0.36 mm, and 0.64 mm. The subjects participated in 14 sessions held on consecutive weekdays. Analysis of the data from six sessions spanning the test period yielded significant main effects (p < 0.001) of handwear and of session on all dexterity tests. Mean times were best with bare hands and poorest with the 0.64 mm gloves. Performance with the gloves improved over sessions to the extent that the results with gloves approached or surpassed performance levels achieved with the bare hands during the early sessions. Regression analyses carried out on the data from the last three sessions revealed a linear increase in times to test completion as a function of increases in thickness of the handcovering. The occurrence of damage to the gloves, in the form of punctures and tears, was inversely related to thickness. The findings suggest that selection of the thinnest glove material compatible with protection from the chemical environment and practice working with the handwear will result in relatively efficient manual performance.
