The purpose of this study was to identify the most desirable cranking rate to be used by paraplegic individuals during submaximal arm training programs. Eleven healthy paraplegic males (M age = 28.8 years) with lesion levels ranging from T4 to T12 served as subjects. Arm exercise loads for the four submaximal cranking rates studied (50, 60, 70, and 80 rpm) were set to elicit 60% of peak V̇O2. Duration of the submaximal tests was 15 min. V̇E, V̇O2, RER, HR, and differentiated RPE were recorded each minute throughout the 15-min test. A randomized block ANOVA and Duncan’s post hoc analysis indicated that 80 rpm produced significantly higher (p <.05) values for HR, absolute V̇O2, V̇E, V̇CO2, and V̇E/V̇O2 than any other rates. Cranking at 70 rpm resulted in significantly higher (p <.05) values for O2 pulse, while relative V̇O2 was significantly higher (p <05) at 70 rpm than at all other rates except 80 rpm. RPE was significantly higher (p <.05) at 50 rpm than at 60 or 70 rpm, with no difference between 50 and 80 or 60, 70, and 80. The authors concluded that 70 rpm was the most appropriate cranking rate for paraplegic males to use during arm training programs.
George T. Hardison Jr., Richard G. Israel, and Grant W. Somes
Mollie G. DeLozier, Richard G. Israel, Kevin F. O’Brien, Robert A. Shaw, and Walter J. Pories
This investigation quantified body composition and aerobic capacity and examined the interrelationships of these measures in 20 morbidly obese females (M age = 34.6 yrs) prior to gastric bypass surgery. Fifteen subjects were hydrostatically weighed at residual lung volume in order to determine body composition. Eighteen subjects performed a maximal modified progressive treadmill test to determine aerobic capacity. Results indicated that the 15 subjects who were weighed hydrostatically were heavier (M wt = 132.34 kg) and fatter (M % fat = 53.18) than any previously described individuals. Relative weight, which is used as a criterion to determine surgery eligibility, was not significantly (p > .05) correlated to percent body fat. Mean aerobic capacity (V̇O2 = 14.99 ml • kg-1 mir-1) was comparable to Class III cardiac patients and was limited by the individuals’ extreme body weight. Since relative weight was shown to be an insensitive measure of obesity, it is recommended that percent fat be measured and used as a means to determine eligibility for gastric bypass surgery. Further study of these individuals is warranted in order to determine what effects large weight loss following surgery will have on parameters of body composition and aerobic capacity. Understanding how large weight loss affects these parameters will aid in designing effective postsurgical exercise rehabilitative programs for future patients.
Tibor Hortobágyi, Richard G. Israel, Joseph A. Houmard, Kevin F. O'Brien, Robert A. Johns, and Jennifer M. Wells
Four methods of assessing body composition were compared in 55 black and 35 white, Division 1, American football players. Percent body fat (%BF) was estimated with hydrostatic weighing at residual volume, corrected for race; seven-site skinfolds (7 SF), corrected for race; bioelectrical impedance analysis (BIA); and near-infrared spectrophotometry (NIR). Percent body fat with HW in blacks (mean = 14.7%) and whites (19.7%) did not differ (P > .05) from %>BF with 7 SF (blacks, 14.7%; whites, 19.0%). In relation to HW, BIA significantly (P < .05) overpredicted (blacks: 20.1%, SEE = 3.2%; whites; 22.3%, SEE = 4.3%) and NiR underpredicted %BF (blacks; 12.6%, SEE = 3.9%; whites; 17.7%, SEE = 3.6%). The contribution of BIA variables (resistance, phase angle, conductance) and NIR optical density to predict %BF was trivial compared to body mass index. It appears that race may not substantially influence %BF prediction by NIR and BIA. It was concluded that when considering the cost and expertise required with NIR and BIA, SF measurements appear to be a superior alternative for rapid and accurate body composition assessment of athletes, independent of race.