The Difference in Efficiency and Pulmonary Function While Performing Cycle Ergometry on Land and in Water

The purpose of this study was to quantify the difference in net efficiency and pulmonary function while performing cycle ergometry on land in water. Thirty healthy adults (mean ± SD, age, 20 ± 2 y; stature, 165 ± 10 cm; mass, 70 ± 5 kg) participated in one day of testing consisting of both land and water conditions. Heart rate, O2 consumption, CO2 production, rated perceived exertion, and minute ventilation were measured for both conditions at rest, pedaling at no resistance, 50, and 100 W for two minutes. A repeated measures two-way ANOVA with post hoc tests was used to analyzed the data. The magnitude of physiological functions (rated perceived exertion, minute ventilation, energy expenditure, & heart rate) increased at higher resistance levels (50 and 100W) in water as compared to land. Efficiency decreased at 50 and 100W in water. Energy expenditure and minute ventilation both increase while cycling in water, resulting in a decrease of efficiency by 4.61%. This is due to the drag forces associated with fluid dynamics. This study and its results add to the understanding of water exercise and are beneficial to the rehabilitation and the general well-being and health of the population