One-Hour Workout: Swim Endurance Builder

This progressive workout will help you build your aerobic fitness and hone your pacing in the water.

Photo: Cameron Spencer/Getty Images

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When it comes to classic swim workouts that help build aerobic endurance, they don’t come much simpler than this one. It’s also a super versatile workout that can be adapted based on fatigue and time available.

You’ll begin with a 10-minute easy swim, gradually increasing the effort (or Rate of Perceived Exertion, RPE) to a 6 out of 10 by the end of the warm-up. Then do a progressive pull prep set, which starts with a 200 and drops 25 each swim, so: 200, 175, 150, 125, 100, 75, 50, 25. Gradually build the effort to a 8-8.5 out of 10 by the 50 and 25. Use a pull buoy and, depending on what swim training gear you’re used to, you might also want to include a front-mounted snorkel, ankle strap/band, and paddles.

The main set sees the progressive pattern continuing with 8 x 100 or 8 x 150 (depending on time/fitness/preference), building effort every two intervals. By the final two intervals (#7 & #8) you should be working at a solid 8-9/10 RPE. Take 30 seconds rest between each 100 or 150. By increasing the effort/intensity every two swims, this forces you to really hone in on your pacing. You’ll want to make sure you control the effort in the opening intervals, otherwise by the time it comes to the final two you’ll be struggling.

Wrap it up with a 200 easy freestyle/backstroke cool-down.

Note: If you are short on time or feeling fatigued, do 6 x 100/150 for the main set and begin the prep set at 150, not 200.

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One-Hour Workout: Swim Endurance Builder


10 min. smooth swim

Prep. Set

Pull: 200, 175, 150, 125, 100, 75, 50, 25 – building effort to 8-8.5/10 RPE by the end

Use pull buoy and your choice of: snorkel, ankle strap/band, paddles

Main Set

8 x 100-150 on 30 sec. rest – building effort every 2 intervals, the final 2 should be at 8-9/10 RPE


200 easy freestyle/backstroke

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