Several benefits in the physical fitness components can be acquired with the practice of aquatic exercises. Moreover, water provides an environment for the practice of exercises with reduced impact on lower limbs and major or minor cardiorespiratory overload, depending on the movements performed. However, such exercises can produce physiological responses different from those on dry land, since important physiological alterations occur during immersion, being important to understand them at rest for better prescription in this environment. The present study has the purpose to review studies about the heart rate behavior and the oxygen uptake during immersion at rest and to understand the factors that influence in this behavior. Several investigations indicate that heart rate at rest is reduced with immersion in aquatic environment; however, it is important to highlight that factors such as water temperature, body position, immersion depth and initial heart rate may minimize or maximize such responses. The studies which approached the oxygen uptake responses are not conclusive; however, contrary to heart rate, the same ones indicate similar or greater response during immersion at rest. Thus, it can be concluded that, due to the verified cardiorespiratory alterations with immersion in aquatic environment, the prescription of exercises in this environment must be differentiated from exercises on dry land.
heart rate; oxygen uptake; aquatic environment
