By Mandi Blackwelder, DVM CCRP

What is an underwater treadmill?

Yes, just as it sounds. It is a treadmill where pets walk on a treadmill in a tank of water for rehabilitation and conditioning.

How on earth do you get a dog to do that?

The beauty of the treadmill tanks today is that the dog walks up a ramp into an empty tank – usually lured by a treat the first time.   The water comes in slowly around their feet from around the sides of the treadmill belt. Just as the dog says to himself “Hey, there’s water coming up in here,” the belt starts moving. So now he’s thinking “Hey, the ground is moving, I’d better walk,” and he stops wondering about the water.   It’s amazing to watch and it is quite rare that a dog will try to jump out. The occasional dog will just ride the belt to the back of the tank, but with a bit of encouragement, once he gets his walk going on the belt, he does fine.

Who can it help?

  • Arthritic dogs – this is my favorite tool for these old guys. They feel young again in the tank.
  • Post operative pets – orthopedic. Broken limbs, ruptured cruciates, and a variety of other orthopedic surgeries will benefit
  • Neurological pets – gets them walking again!
  • Blood clots — especially cats
  • Athletes – gives them a conditioning edge of endurance and strength

What about cats? (Cats hate water, you know)

Surprisingly, cats have a similar reaction to dogs. With the belt moving, they have to keep walking or they will fall. All pets know this intuitively which makes it hard to plan how to place feet in order to jump, so they don’t.

How is water helpful? 

  • Buoyancy: Quite simply, we weight less in water. So if your pet has a sore or weak leg, she will bear more weight on it in water. This maintains the muscles in the affected limb.   For many dogs, just knowing they are buoyant will increase their confidence.   Sore arthritic old guys will walk like they used to and LOVE it. Paralyzed dogs who can’t yet walk on land, have reflexes that kick in when the belt moves underneath them . Then they think “Hey, look at ME, I’m walking!!” and put in more effort. And dogs recovering from surgery, who KNOW that leg hurts, take a few steps and realize that it hurts less.
  • Heat: The water in the treadmill is warm. Warmth soothes sore muscles, loosens tight tendons and increases blood supply to healing tissues. At about 85 degrees, it is “bathtub warm” but not so warm they overheat with exercise.
  • Hydrostatic pressure: This is a fancy way of saying that the water pushes in slightly on the dog. For a pet with swelling, that minor amount of pressure (coupled with the increased blood flow from the heat) it helps return that fluid to the body. Less swelling means less pressure, less pain and better movement.
  • Cardiovascular health: For athletic patients that need conditioning, the underwater treadmill is a remarkable tool. The walking speed can be increased to running speed (up to 7mph on some machines). The level of the water can be adjusted for maximum resistance.   Patients build endurance, increase cardiovascular capacity, strengthen muscles and maintain flexibility which reduces the chances of injury.   (As a note, I have seen this tool become a crutch for many owners of athletic dogs. Using the treadmill is NOT a substitute for balance work and physiotherapy, but an addition. Most athletic injuries do not happen on a straight run, they happen in a turn or jump which requires physiotherapy and other training to prevent).

I have a bathtub at home, can’t I just walk my dog in that?

Walking in water and walking on a treadmill in water do two different things. Walking in water is about resistance – advancing your legs forward in water is harder than in air.   The treadmill and the bathtub accomplish this at water heights above the elbow. But the treadmill portion is essential to healing lameness and rebuilding nerve function because it is the consistently the same pace requiring each foot to bear weight evenly. You can’t limp on a treadmill. For pets recovering from paralysis, when the ground is moving under their feet, the legs will reflexively walk, even if they can’t walk on land. This retrains the nerves and strengthens the muscles involved in walking.