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RideThreshold

Seiler 4 × 16

4 × 16 min at the highest sustainable power, 2–3 min easy

Time
1h39
Hard
1:04:00
in zones 4–5
Difficulty
Very hardDifficulty 4 of 5 — Very hard
Inspired by
Stephen Seiler

What we typed

Warm up 15 min building from 50% to 75% FTP. 4 × (16 min at 93–97% FTP, the highest you can hold for all four; 2 min 30 s easy at 50% FTP). Cool down 10 min at 50% FTP.

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

Describe your own

The session

4 steps

Warm up

Build from 50% to 75% FTP.

15 min50–75% FTPZ2
4×16 min

Rep

Highest you can hold for all four.

16 min93–97% FTPZ4

Easy

2m 30s49–52% FTPZ1

Cool down

10 min49–52% FTPZ1

Targets

Set as a share of your FTP. Your watch applies it to the FTP in its own settings, so it keeps up as that changes.

50–75% FTP
93–97% FTP
49–52% FTP

Scaled version

3 × 12 minutes at 90–95% FTP.

Build the scaled version in Forge

About this session

The story

The longest of the three formats Stephen Seiler's group compared (4 × 4, 4 × 8 and 4 × 16 minutes). In that study it gained a little less than 4 × 8 — but it's a superb long-threshold session in its own right.

What it trains

Long threshold work with very short breaks — over an hour of near-threshold riding.

Who it's for

Well-trained endurance riders and long-course triathletes.

Sources 1
  1. Adaptations to aerobic interval training: interactive effects of exercise intensity and total work duration — Scandinavian Journal of Medicine & Science in Sports (PubMed), 2013

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