Love water-based activities? You may be helping your health more than you thought.

A small study by Howard Carter of the University of Western Australia School of Sport Science suggests that immersing the body in water to the level of the heart increases blood flow through the brain's cerebral arteries, thus improving vascular health and cognitive function.

"Studies on the positive effect of exercise on heart health have been numerous, but we are taking a different angle and are interested in the link between heart and brain health," says Carter. "To our knowledge, ours is the first examination of the effect of graded euthermic [warm] water immersion on cerebral blood flow."

Nine healthy males participated in the study and were asked to stand in a tank while remaining as still as possible. Subjects were given a 10-minute rest period before "three submersible water pumps filled the tank at a constant rate with euthermic water (30 C) to the level of the heart's right atrium."

Study results showed a 14 per cent blood flow increase to the middle cerebral artery and a nine per cent blood flow increase to the posterior cerebral artery when subjects were immersed in water.

Carter says findings point to potential benefits of aquatic-based activities.

"As with land-based exercise, different types of water-based activities, such as water aerobics and swimming, have slightly different effects on heart function and cerebral blood flow so each would require further investigation," he says.

Researchers are now working on a six-month exercise training study to determine if water-based exercise results in consistently greater increases in cerebral blood flow compared to land-based workouts. The research team will also further examine whether water workouts "greatly improve" vascular health and cognitive function.