Acute Physiological Effects of Exercise in Water

Abstract

The acute effects of exercise in water may differ from those on land because of the physical properties of the water. The increased hydrostatic pressure causes a hypervolaemia, which influences the haemodynamic effects of exercise in water. Water resistance and temperature affect the metabolic pathways utilized during exercise. As a result the use of land-based norms to prescribe and monitor water exercise may be unreliable. This review focuses on upright exercise in water, namely cycle ergometry and walking/running.Oxygen consumption (VO2) and heart rate are influenced by the depth and temperature of the water, exercise mode and speed. For example, cycle ergometry on land and in water yield similar maximal oxygen uptake (VO2max) responses. However, shallow water running elicits a VO2max which is approximately 10% lower than similar land activity. Deep water running yields a 26% lower VO2max than on land.Cycle ergometry and walking/running in water have been shown to provide cardiovascular benefits in line with the American College of Sports Medicine guidelines. However a complex interaction exists between the water, exercise and subject variables which will affect the exercise response. Future research should focus on the biomechanical and neuromuscular effects of exercise in water at various depths.