Water exercise is a fun and energizing workout that can provide aerobic, strength and flexibility training. Aquatic dumbbells are shaped like the weighted dumbbells used for land exercise, but are light because they are made of foam or plastic floats attached to a plastic rod. The weights you use on land work your muscles as you raise them against gravity, but in the water, the resistance is opposite. The dumbbells resist your efforts to lower them. The bigger the foam or plastic floats on your aquatic dumbbells, the more resistance they will provide.

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