The Self-Powered Underwater Treadmill is swimming pool exercise equipment designed for use by seniors and individuals with lower extremity disabilities or arthritis. This unit has a flow-through, high-speed turbine that dampens the walkway belt movement for safe boarding and exponentially increases resistance as the walking or running speed increases. It also features a double-sided platform. With the platform positioned roller side up, users can enjoy a foot massage while taking a leisurely stroll. Flip the platform over to increase the baseline resistance for a more intense workout. The stainless steel handrail can be removed for swimming, inverting the platform, servicing, shipping, or storage. Large rounded corners and soft molded feet protect the user's toes while holding the treadmill in place and protecting the pool interior.