Peak oxygen uptake and respiratory function in persons with spinal cord injury.

This study investigated the association between peak oxygen uptake (peak VO2) during arm cranking exercise and respiratory function in paraplegics. Fourteen male paraplegics were recruited for the present study. The subjects were grouped according to the level of injury into the HL (Th3-Th8) and LL (Th11-L3) group. Prior to the maximal test, pulmonary function, including vital capacity (VC) and residual volume (RV), was measured in the sitting position. Mean peak VO2 in the LL group (1662 ml.min-1) was significantly greater than that in the HL group (1357 ml.min-1), corresponding to 82% of that in the LL group (P < or = 0.05). In respiratory function, the HL group showed marked restrictive impairment of ventilatory function. That is, VC and RV were significantly lower in the HL group than in the LL group (P < or = 0.05). The reduction in VC and RV is related to the degree of loss of control in respiratory functioning muscle mass. However, there was no clear-cut correlation between respiratory function and peak VO2 expressed as a function of body mass (ml.kg-1.min-1). In addition, a multiple linear regression analysis revealed that RV and VC were not associated with peak VO2 (ml.min-1) in contrast to the importance of body mass. It seems reasonable to conclude from these results that respiratory function is not an important factor in determining peak VO2 in the paraplegic.

[Body density assessment utilizing skinfold thickness and age in Japanese men].

A study was conducted to investigate the validity of skinfold-based prediction equations for body density (g/ml) by Nagamine and Suzuki (1964), and to formulate more convenient and more useful equations for predicting body density from skinfold and age in men. Subjects of the study were 257 healthy men aged 19-60 years in or near Nagasaki City. The regression equation for the dependent variable, body density, was determined by hydrostatic weighing. Independent variables included eight skinfolds, the sum of two skinfolds (triceps, subscapular), the sum of three skinfolds (triceps, subscapular, and abdominal), age, and body surface area. Skinfolds were measured with an Eiken-model skinfold caliper. Age (mean 33.1, range 19-60 yrs.), weight (mean 65.3, range 46.6-107.7 kg), height (mean 168.8, range 152.3-185.4 cm), and body density (mean 1.05874, range 1.00860-1.09020 g/ml) were also recorded. Percent body fat was calculated using the formula by Brozek et al. and ranged from 6.1% to 38.9%. Multiple correlation coefficients (MR) and standard error (SE) of 10 regression equations (A-J) for predicting body density in men were obtained. The best-fitting and the most convenient prediction equation for body density was equation-E.: body density = 1.09556-0.00062 x sum of three skinfolds (mm)-0.00028 x age (MR = 0.815 and SE = 0.0087 g/ml). The equation was cross-validated on a different sample of 45 men. The correlation coefficient between predicted and hydrostatically determined body density was 0.781 (p < 0.001). Equation-E (Tahara's equation) appears to be useful in body density analysis particularly when the subjects are Japanese men, aged 18-50 yrs, with percent body fat 10 to 30%.