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Swim workouts

VO2max Swim: Hard Repeats That Make Fast Laps Feel Easier

Warm up 12 minutes, then swim 4 to 8 hard 2-minute repeats, about 8 out of 10, with 1 minute easy between. It pushes up the most oxygen your body can use.

Why it works: Chapter 27, How hard intervals grow your heart

The workout

33–45 min

VO₂max · Aerobic ceiling, peak oxygen uptake

  1. Warmup

    12 min

    RPE 3/10

    You could keep this up for hours.

  2. Intervals

    4–8 × 2 min

    RPE 8/10 · 1 min easy swim between

    You could hold this for a few minutes.

  3. Cooldown

    10 min

    RPE 3/10

    You could keep this up for hours.

The lesson

  1. 1

    Warm up for 12 minutes

    Easy swimming, building a little over the last few minutes. No drills today. The repeats need you fresh.

  2. 2

    Swim 2 minutes hard

    Ask how long you could keep this up: a few minutes at most. If it feels like you could only last thirty seconds, you are going too fast. About 8 out of 10, freestyle, body long. Breathe as often as you need to.

  3. 3

    Swim 1 minute easy

    Keep moving, slow and relaxed. One minute is not enough to recover fully, and that is the point. Your breathing stays high going into the next repeat.

  4. 4

    Repeat 4 to 8 times

    Your app sets the count. Every repeat at the same effort. The last should look like the first.

  5. 5

    Even repeats beat fast ones

    If your stroke or your effort falls apart before the last repeat, swim the remaining repeats easy. Even repeats matter more than one fast one.

  6. 6

    Cool down for 10 minutes

    Easy swimming, any stroke, until your breathing is calm again.

Watch for

  • Going all-out on the first repeat. The later ones fall apart and you spend less time at the effort that counts.
  • Easing off to a comfortable pace. It turns into a threshold swim and your ceiling never gets pushed.
  • Stopping during the easy minute. Your breathing drops too far and the next repeat starts from scratch.
  • Fighting the water when tired. Your head lifts and your stroke shortens, and you work harder to go slower.

Questions

What is VO2max, and does swimming raise it?

VO2max is the most oxygen your body can take in and use, the ceiling on your aerobic fitness. Hard repeats of a few minutes are the standard way to push it up, and once it rises, every hard swim below it costs you less. In water the work falls on your heart and lungs with no impact on your joints.

How hard should VO2max intervals feel?

About 8 out of 10, an effort you could keep up for a few minutes at most. If you could hold it much longer, it is too easy; if it feels like you could only last thirty seconds, you are going too fast.

How often should I do a VO2max swim?

Your plan spaces them for you: at most one a fortnight, counting VO2max runs, rides and swims together, and only once your body handles threshold work.