Kiger (2013) THE CARDIOVASCULAR RESPONSES OF RUNNING ON AN UNDERWATER

This study examined the cardiovascular responses of running on an underwater treadmill at two different water temperatures (95°F and 104°F) compared to land-based running in healthy, college-aged individuals. Participants completed trials at progressive speeds and inclines, with physiological variables like heart rate (HR), oxygen consumption (VO₂), and perceived exertion (RPE) measured.

Key findings include:

• Heart Rate: Running on the underwater treadmill resulted in lower HR compared to land-based running, demonstrating the cardiovascular efficiency of water-based exercise.
• Oxygen Consumption: VO₂ was also lower in water, likely due to the buoyancy reducing joint stress and muscle load.
• Perceived Exertion: RPE was similar across all trials, suggesting that participants felt comparable effort levels regardless of environment.

Water temperature did not significantly influence physiological responses between 95°F and 104°F trials. However, higher temperatures were reported as less comfortable due to increased heat stress and dehydration risk. These findings highlight underwater treadmills as a viable alternative to land-based exercise, offering reduced cardiovascular strain while maintaining training intensity.