Swimming

Swim to your CSS, not a stranger's.

Every set is written as a share of your critical swim speed, so the pool sessions your coach plans are pitched at your threshold — and the swims land on the same fitness and fatigue curve as everything else you train.

38cited swimming workouts and 0 plans, scored as sTSS from critical swim speed.

What your coach sees

What a swimming coach needs. Exactly.

sTSS, from your critical swim speed

A 400 m / 200 m test sets your CSS, and every swim is scored against it, with the intensity cubed because water drag climbs that fast. Easy lengths stay cheap; threshold sets cost what they should.

SwimmingExample
Line
Lengths · 20 × 100 at CSS
Load
sTSS from critical swim speed
Library
38 workouts · 0 plans

Drills to open water, each one sourced

Catch and rotation drills, aerobic 400s, CSS 100s, Red Mist, race-pace sets, sighting, drafting, starts and cold-water acclimation, transcribed from a research dossier with citations on every entry. Open-water sessions carry their safety rules with them.

Ready for the triathlon and the open-water race

Swim sessions sit in the same week as your riding and running, so the coach can space the hard days across all three — and the open-water work is there for the race that isn't in a pool.

LibrarySwimming
Workouts
38, each cited
Plans
0 multi-week
Curve
Fitness · fatigue · form

No invented numbers.

Load is sTSS — your swim's pace measured against your critical swim speed, with intensity cubed, weighted by how long you held it.

In the catalog38 workouts · 0 plans
Hand-authored from a cited research dossier. Every entry carries its sources and an honest note about what the evidence does and doesn't say.
DisciplinesPool · Open_water
Tracked as distinct work, because they are.
Arrives on its ownStrava · Apple Health
Matching activities import automatically, so you don't log the same session twice.
Your coach, in your AI appClaude · ChatGPT · any MCP client
Helios runs no model of its own. It hands your coach the numbers and the coach lives where you already are.

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