Patients who have been recovering in an ICU, mechanically ventilated for a prolonged period of time, are usually unable to even move their limbs against gravity. Also their ability to breathe by themselves has been compromised. Aquatic therapy can be very helpful for these patients. In the water, (slow) movement is much easier and because of the pressure effects, central blood volume increases so that the heart can act more efficiently. The aquatic environment is very effective in increasing muscle strength and breathing ability.