One-Hour Workout: Fast 50s

Build your swim speed—and kick strength—with this simple pool workout.

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As a triathlete, a lot of your workouts don’t need to be fancy or complicated, they just need to be consistent and have a clear objective and focus. This swim session is straightforward and “gets the job done,” helping you to build aerobic endurance, speed, and work on your kick—and we all know how much triathletes need to do that!

The warm-up should be progressive in effort, with the opening 400 very easy and relaxed. None of it should be above 5-6/10 RPE (rate of perceived effort). Save that for later.

Think of the 16 x 25 swim as a prep set for the main set—they are designed to “open your engine” and get you going for the work ahead. Progress through the 16 x 25 in blocks of four, so lap 1 is easy, lap 2 is easy-moderate, lap 3 is moderate-fast, lap 4 is fast. Repeat that pattern four times through. Take 10 seconds rest between each 25.

The progressive theme continues into the main set with 5 x 50 swim, progress 1 through 5, followed by 5 x 50 kick, progress 1 through 5. This means you should be hitting maximum effort on the fifth rep—no excuses! Take 10-15 seconds between each 50. Repeat this for two or three rounds, depending on speed/time.

Swim a relaxed 200-300 as cool-down.

Fast 50s


400 swim, 300 pull, 200 drill, 100 kick

Main Set

16 x 25, progress 1-4 (four times through) with 10 seconds rest between each 25

2x or 3x
5 x 50 swim, progress 1-5
5 x 50 kick, progress 1-5
Take 10-15 seconds rest between each 50


200-300 easy swimming

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