E. M. Bernauer

Evaluation of a new air displacement plethysmograph for measuring human body composition.

A new air displacement plethysmograph, the BOD POD (BP), was evaluated in comparison to hydrostatic weighing (HW). Sixty-eight adult subjects (26 F, 42 M) varying widely in age (range 20-56 yr), ethnicity, and fatness participated in this study. Same-day test-retest reliability was assessed in a subsample of 16 subjects (9 F, 7 M) and validity was assessed in all subjects (N = 68). The test-retest coefficients of variation (CV) for %FAT measured by BP (%FATBP) and HW (%FATHW) were not significantly different (1.7% +/- 1.1% and 2.3% +/- 1.9% for BP and HW, respectively (mean +/- SD)), indicating excellent reliability for both methods. Validity of percent fat measured by the BP (%FATBP) was also excellent. The mean difference in %FAT (BP - HW) was -0.3 +/- 0.2 (SEM), with a 95% confidence interval of -0.6 to 0 %FAT. The regression equation (%FATHW = 1.86 + 0.94 %FATBP; r2 = 0.93, SEE = 1.81) was not significantly different from the line of identity (%FATHW = %FATBP), and did not differ by gender. These findings indicate that the BOD POD is a highly reliable and valid method for determining %FAT in adult humans in comparison to HW. This new method has several advantages over HW in that it is quick, relatively simple to operate and may be able to accommodate special populations such as the obese, elderly, and disabled.

Moderate resistance exercise program: Its effect in slowly progressive neuromuscular disease

A 12-week moderate resistance exercise program was performed by 27 patients with slowly progressive neuromuscular diseases (NMD) and 14 control subjects (CTL) in order to determine safety and efficacy of a strengthening program. A 3-day per week submaximal regimen of home exercise using ankle and wrist weights and hand grip exerciser was prescribed. One side of the body was randomly chosen for exercise. Subjects were tested for maximal isokinetic and isometric strength at baseline and after weeks 4 and 12 of the training protocol, and the prescribed amount of work was gradually increased throughout the program. Both the NMD and CTL groups demonstrated significant (p < .05) increases in most strength measures. Both groups responded similarly to the exercise program, and strength gains did not significantly differ between the exercised and nonexercised limbs in either group. This study provides evidence that a 12-week submaximal strength training program is practical and safe in slowly progressive NMD and produces moderate improvement in measured strength.

Exercise reverses depressed metabolic rate produced by severe caloric restriction

The effects of caloric restriction and exercise on resting metabolic rate (RMR) were studied in five obese humans. Subjects consumed a 500 kcal.d-1 diet for 4 wk, with the subjects remaining sedentary during the first 2 wk and then exercising 30 min daily at 60% VO2max during the last 2 wk of caloric restriction. After 2 wk of dieting, RMR decreased to approximately 87% of the pre-dieting control value. Over the last 2 wk of dieting with the addition of daily exercise, the fall in RMR was reversed as it returned to the pre-dieting level. In summary, daily exercise reversed the drop in RMR associated with severe caloric restriction.

Isometric and Isokinetic Measurement of Hamstring and Quadriceps Strength

This study evaluates quadriceps strength at varying movement velocities in a group of healthy subjects. Specific objectives included (1) investigating the effect of angular velocity on peak torque (PT) (2) investigating the effect of angular velocity on joint angle at peak torque (JAPT) and (3) evaluating whether the use of a relatively new isokinetic testing device yields new insights to previously accepted relationships between angular velocity and PT or JAPT. Twenty healthy subjects were tested for isometric and isokinetic knee extension and flexion strength on a LIDO Active Isokinetic Rehabilitation System at velocities of 0 degrees, 60 degrees, 120 degrees, and 180 degrees/sec. Isometric PT (0 degrees/sec) was found to be highly correlated with isokinetic PT for both extensors and flexors at all velocities (r = .88-.93, p less than .01). PT declined significantly as angular velocity increased for both extension (p less than .01) and flexion (p less than .05). A relationship between isometric and isokinetic JAPT was significant for extension only at 60 degrees and 180 degrees/sec (r = .48-.52, p less than .05). These results indicate that knee isometric and isokinetic PT as measured on the LIDO Active system are highly related for both extension and flexion. PT declined as isokinetic angular velocity increased. Isometric and isokinetic JAPT are significantly related only for extension.

Exercise during the menstrual cycle: variations in physiological baselines.

Abstract Eighteen healthy undergraduates, free of any acknowledged menstrual disorders, performed a standard bicycle ergometer exercise on the first and the fourteenth day of the month under controlled environmental conditions. Postabsorptive measurements were made of blood hemoglobin, blood hematocrit, heart rate, and blood pressures at rest and following exercise. Heart rate and systolic blood pressures taken at rest varied significantly between all the experiments, regardless of time relative to the menstrual cycle. Resting blood hemoglobin and hematocrit, however, varied significantly relative to the time of the experiment with respect to the menstrual cycle. All measurements made following the exercise failed to show a statistical significance between experiments. The results suggest that variations in blood hemoglobin and hematocrit are related to the menstrual cycle at rest but apparently are completely masked by a moderate bout of exercise. The physiological bases of the cyclic changes and the exe...

The effect of selected pace variations on the oxygen requirement of running a 4:37 mile.

Abstract Nine experienced middle distance runners completed three experimental runs of equal distance and duration on a motor driven treadmill. Each run varied according to pace (steady, fast-slow-fast, and slow-fast), with the individual order of runs rotated to prevent bias in this respect. Heart rate and oxygen consumption measures were taken during rest, exercise and a 30-minute recovery period. Oxygen consumption values for the 30–90 minute recovery period were extrapolated from earlier measured recovery values. Analysis of data indicated that there were no significant differences among the three pace plans in net oxygen intake during the runs. However, the total oxygen debt value for the steady pace was lower than that for either the fast-slow-fast or the slow-fast paces. The total net oxygen requirement for the steady pace was found to be significantly less than that for the other two paces with no significant difference between the fast-slow-fast and slow-fast paces. It was concluded that a steady...