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Phelps 10 × 400 Descending Send-Off

10 × 400 free, send-off drops 5 s each: 4:45 → 4:00

Elite session. As written this is for very experienced, high-volume athletes. Most people should start with the scaled version under the steps.
Time
≈1h06
Hard
≈43:45
in zones 4–5
Difficulty
EliteDifficulty 5 of 5 — Elite
Elite · scaled option below
Inspired by
Michael Phelps and Bob Bowman

What we typed

25 m pool. Warm up 800 easy mixed strokes. Then 10 × 400 freestyle at moderate-to-hard effort with send-offs dropping 5 s each rep: 400 on 4:45, 400 on 4:40, 400 on 4:35, 400 on 4:30, 400 on 4:25, 400 on 4:20, 400 on 4:15, 400 on 4:10, 400 on 4:05, 400 on 4:00. Note: elite send-offs, scale to yours. Cool down 300 easy.

Fit File Forge built the steps below from these words — the same steps your watch gets.

Describe your own

The session

22 steps

25 m pool

Warm upMixed

800 mEasyZ2

10 × 400 m· Hard· Freestyle

Send-off 4:45 → 4:00 · 5 s less each

Cool down

300 mEasyZ2

Targets that fit you. Swims use Garmin's effort levels (easy, moderate, hard, all out…). Send-offs listed as clock times are the original, elite intervals — scale them to leave yourself the rest the set intends.

Scaled version

5 × 200 with the send-off dropping 5 seconds each from a comfortable start (e.g. 3:30 → 3:10).

Build the scaled version in Forge

About this session

The story

A Bob Bowman workout for Michael Phelps at North Baltimore Aquatic Club included 10 × 400 free starting on a 4:45 interval and cutting it by 5 seconds each swim. These are elite send-offs; scale them to yours.

What it trains

Aerobic capacity and pacing under a shrinking rest interval.

Who it's for

Elite and very strong club swimmers as written. Everyone else: the scaled version.

Sources 1
  1. Selected Workouts for Michael Phelps - Bob Bowman (North Baltimore Aquatic Club) — USA Swimming (archived), 2004

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