In the present study, three groups of young adults (N=4, N=153, N = 29) were used separately or together to test for the effects of diurnal variation, of diet or physical activity on bioelectric impedance and of the possible changes in bioelectric impedance during the menstrual cycle in women taking oral contraceptives and in women not taking oral com traceptives. In young adults of normal stature and weight, there was no significant association between measures of bioelectric resistance and time- of-day or between interval from previous meal or drink and means of the differences of body composition variables estimated from underwater weigh' ing less corresponding values predicted from sex-specific equations using bioelectric resistance and anthropometry. In the women who did not participate in some form of regular physical activity, the means of the differences of body composition variables estimated from underwater weighing less corresponding values predicted from bioelectric resistance and anthropometry were significantly different from corresponding mean differences for women who did participate in some form of regular physical activity. The corresponding findings in the men were not significant. Also, the effects of oral contraceptive usage, and of the timing within the menstrual cycle on measures of bioelectric resistance were not significant. Except for the effect of the absence of exercise in the women, the effects of the physiologic variables and oral contraceptive usage upon bioelectric impedance were not significant.
Chumlea, Wm. Cameron; Roche, Alex F.; Guo, Shumei; and Woynarowska, Barbara
"The Influence of Physiologic Variables and Oral Contraceptiveson Bioelectric Impedance,"
2, Article 7.
Available at: https://digitalcommons.wayne.edu/humbiol/vol59/iss2/7