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.