Find the heart of the session first

Before cutting anything, identify the main set. If the workout is built around 10 × 100 m at a steady pace, that block probably matters more than two small supplementary sets. If the goal is technique, the heart of the workout may instead be a drill-to-swim progression.

Ask yourself: if I could keep only one block after warming up, which one would still make this session worth doing? Protect that block.

Reduce volume before rewriting the instruction

To save time, it is often cleaner to reduce the number of repeats than to change every distance, effort, and rest instruction. Ten 100s can become six 100s at the same pace with the same recovery. The workout is shorter, but it still speaks the same training language.

Dropping a few repeats, removing a second similar set, or cutting an accessory block is usually better than squeezing every rest interval. Halving all the rest can change the training load much more than expected.

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What not to cut first

Do not go straight from the locker room into maximal work. Even in a short session, keep a few minutes to settle into the water. And when the main set depends on demanding technique, do not remove the only block that helps you establish that technique first.

Example: turn 55 minutes into 35

Imagine 400 m warm-up, 8 × 50 m drill/swim, 12 × 100 m steady endurance, then 200 m easy. A shorter version could be 300 m warm-up, 4 × 50 m drill/swim, 7 × 100 m at the same pace, and 100 m easy. You preserve the entry into the session, the technical cue, and most importantly the main set.

It is not mathematically the same workout, but the purpose is still recognizable. That is much more useful than keeping every line and rushing through all of it.

Accept that the adapted workout is a new version

The goal is not to pretend 35 minutes equals 55. You swam less volume, and that is fine. What matters is that you made a deliberate choice about what to keep.

Over time, you can even create short versions of your favorite sessions: same purpose, simpler structure, clear minimum. Busy days then become an organization problem rather than a reason to swim randomly.