1. A practice or exercise to test or improve one's fitness for athletic competition, ability, or performance.
2. A test of one's ability, capacity, stamina, or suitability.
3. An undertaking or plan intended to resolve a problem of indebtedness, especially in lieu of bankruptcy or foreclosure proceedings.

Give yourself plenty of time to warm up and cool down with easy walking or gentle stretching. Then speed up to a pace you can continue for five to 10 minutes without getting overly tired. As your stamina improves, gradually increase the amount of time you exercise.

For getting started, the biggest difficulty in adults over 30 learning to swim is psychological, not physical. Many adults that haven't learned to swim have had a life of avoidance of water and have some degree of fear or discomfort around water.

It is possible to learn to swim by yourself. The shallow end of a swimming pool is a good place to learn to swim by yourself. Swimming involves breathing, kicking with your legs and stroking with your arms. These are things you can practice one at a time in shallow water.