Hot tubs A swim spa is a tub that allows you to swim continuously against a water current. It acts as a smaller swimming pool in the sense that you can swim just like in a regular pool, but you will not “hit the wall” or have to turn around to continue to swimming. Swim spas also come in split-models, with a hot tub spa in one end and a swimming area in the other end. Swim spas tend to be larger than hot tubs, and provide the absolute best swimming exercise work out, using the least amount of space in your home or yard. A swim spa provides you a place to exercise, relax the mind and body, or spend time with family and friends.