A 3000-yard workout is 120 lengths of a 25-yard pool. Swimming all of these lengths at the same pace can bore even the most dedicated swimmer. Including different types of workouts keeps you entertained and improves your technique, muscle strength and cardiovascular endurance. Focus alternately on breath control, different strokes, strength or sprint speed to vary your workout. Do two to five workouts per week to improve your overall swimming speed, endurance and strength.