Use Fins for a Powerful Swim
If you want to bring your lap swimming to the next level, you may want to try using fins for a while. Because they increase the surface area of your foot, you'll get more power and distance from your kicks. They can also help improve ankle strength and flexibility.
Experts say it's best to use fins as an occasional tool for building up kick strength, and not as something you use continually over the long term.
Fins come in different sizes, shapes and materials. If you're not certain which fins are best for your fitness and swimming level, ask a salesperson at your sporting goods store.