Hydrotherapy pool

Buoyancy removes most of the load from joints, so movement that is impossible or too painful on land becomes possible. Water resistance provides strengthening in every direction without any equipment. Hydrostatic pressure reduces swelling. Warm water reduces muscle tone and pain.

Those four effects together are the reason hydrotherapy is often the only place a programme can start, and the reason it is a bridge rather than a destination.

Patients using wheelchairs, patients in the early phase of rehabilitation and patients unable to manage steps need safe entry to the water; ask for pool access at your centre to be confirmed in your plan. Access is frequently the practical barrier that keeps the people who would benefit most out of the water.

Sessions are conducted with a physiotherapist in the water. Contraindications are checked: open wounds, uncontrolled epilepsy, severe cardiac impairment, incontinence without management, and active infection.

Bone and muscle adapt to load. Water removes load, which is exactly why it helps at the start and exactly why a programme that stays in the water stops producing gains.

We use hydrotherapy to get movement started and to keep conditioning going during painful phases, and we move work onto land as soon as it is tolerated. A patient who only ever exercises in water will not be ready to walk on land.

Therapy pools are warmer than swimming pools, which reduces muscle tone and pain and is a large part of why movement becomes possible in water before it does on land.

That warmth is itself a clinical consideration: it increases cardiovascular load, which matters in cardiac and respiratory disease and is checked before the first session.

Not the exercise but the water. Warm immersion raises heart rate and core temperature, and most people fatigue faster than they expect — which is why sessions start short and lengthen rather than the reverse.

It also means that a person who tolerates a long session on land may manage much less here at first, and that is expected rather than a sign of poor progress.

In knee osteoarthritis, about as effective. For knee and hip osteoarthritis, a Cochrane review found moderate-quality evidence that aquatic exercise gives small, short-term improvements in pain, disability and quality of life compared with no exercise 1. When trials in knee osteoarthritis compare water with land directly, the pooled results show no significant difference in pain, stiffness or physical function 2.

The choice between them therefore rests on what a person can tolerate rather than on which medium works better. Water lets exercise begin when land-based work is too painful or too risky, and the programme moves onto land as tolerance improves.