Aqua fitness is considered one of the best forms of physical training since it is low impact and easier on the joints. It is particularly good for rehabilitation programs. A long and narrow lap pool is preferred by those wanting to swim lengths as part of their routine.
Even if your backyard is quite small you can have a pool that allows you to distance swim for exercise. Small pools can be equipped with special jets to create a current to swim against. A pool will fit into any size backyard making it more usable and enjoyable.