Have you ever noticed how people exercising in the pool are smiling, while the people in the gym are grimacing?
If you are exercising for better cardiovascular, endurance and strength benefits (and not nursing a joint, therapy or rehab issue) there may be several reasons for a workout on an underwater treadmill. Aquatic Exercise is recommended for many reasons-
For people not able to exercise on a landbased treadmill for many reasons, they will be able to burn the same or more calories when walking on an underwater treadmill at the same pace as walking on a landbased treadmill.
Track coaches are beginning to require their track athletes to workout in the pool at least twice a week for 2 reasons- fewer injuries(esp. stress fractures) and exercise with increased resistance for potentailly greater speed and endurance.
Marathon runners and ultra marathon runners that want more "mileage" with less chance of injury will be able to run and increase the load.
For the best fitness options, the exercise prescription may include several steps to increasing the exercise load-
Increase the stride length
Increase the speed/tempo
Add ankle fins for increased drag
If there are no joint issues, decreasing the depth of water to as much as waist level will increase the workload- but decrease the other benefits from aquatic exercise.
What should be the proper water depth?
If you are a healthy individual with no therapy, rehab, joint or other issues,
for most people most resources suggest the depth while on the treadmill to be approximately the center of the chest or at the level of the xiphoid process. For most people the pool depth should be between 3 and 4 feet- depending on many factors- please refer to a professional for personal recommendations.
If you have health issues or questions, please consult your doctor, professional trainer, or therapist for recommendations before beginning exercise.