The Role of Oral Contraceptives and Gender in the Responses to Eccentric Resistance-Exercise and Cycling Performance

Abstract

The primary aim of this thesis was to investigate the effect of gender and oral contraceptive use on the responses to eccentric resistance-exercise and endurance-exercise performance. The results of the three experiments conducted to achieve this aim are presented in this thesis. All subjects included in the present experiments were recreationally active individuals (exercised > 3 d·wk-1 for 30 min·session-1) that did not participate in regular cycling exercise or regular resistance-exercise training. The aim of experiment one was to examine the effect of long-term oral contraceptive use on endurance-exercise performance in recreationally-active women. Eight normally-menstruating women, not taking oral contraceptives (WomenNM) and eight women taking oral contraceptives (WomenOC) performed an incremental cycling test to determine peak O2 uptake and to estimate the anaerobic threshold (AnT). Subjects also completed a continuous submaximal cycling test across three work stages (two 6 min work stages performed below the AnT, and one work stage performed above the AnT to exhaustion). Pulmonary gas exchange, heart rate, blood pressure, blood lactate concentration ([La-]), and rate of perceived exertion were measured throughout, and cycling economy was calculated. Physical characteristics were comparable between the groups (p > 0.05). Peak O2 uptake (WomenNM, 2.59 ± 0.50 L·min-1; WomenOC, 2.13 ± 0.20 L·min-1) and O2 uptake at the AnT (WomenNM, 1.47 ± 0.27 L·min-1; WomenOC, 1.18 ± 0.15 L·min-1) were significantly different between the groups (p < 0.05).