The Run to Swim Ratio

The run to swim ratio is about 4:1, meaning that four miles of running equals one mile of swimming. At 8:00 to 10:00 pace, you'd be running 32 to 40 minutes (respectively) for approximately a four-mile run to equate to one mile of swimming.
Counting your strokes will enable your workout to be more efficient. Aim for 24 strokes in a 25-meter pool.
Breathe every two to three strokes when swimming freestyle. You'll tire too quickly if you breathe less often. When taking a breath, turn your head just far enough for your mouth to clear the water. Your hips and legs will sink if you turn too far.
To improve your freestyle stroke, alternate swimming with your fists closed for one lap, then open for the next. This helps your hands develop a feel for the water. Don't begin stroking with one arm until the other one is fully extended in front of you.
Swimming with fins can increase ankle flexibility and strengthen muscles in the quads, hamstrings, calves and abdomen, all beneficial to runners.
If you're new to swimming, aim to swim for 15 to 20 minutes. Start by resting for just five to ten seconds at the end of each lap. Your goal should be to eventually swim without taking any rests.
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