Middle Distance (70.3)
Middle distance triathlon, widely known as 70.3, covers a 1.9 km swim, 90 km bike, and a 21.1 km half-marathon run.
Overview
Middle distance triathlon typically comprises a 1.9-kilometre swim, a 90-kilometre bike leg, and a 21.1-kilometre run, the last of which is a half-marathon.
It is popularly known as '70.3' after the combined legs totalling roughly 70.3 miles, a name associated with the Ironman 70.3 series.
It sits between the shorter Olympic distance and the full long distance, emphasising sustained endurance over several hours.
What defines it
- Approximate distances are 1.9 km swim, 90 km bike, and 21.1 km run (a half-marathon).
- The '70.3' name refers to the roughly 70.3 total miles of the combined legs.
- Steady pacing and a nutrition strategy matter across a race that usually lasts several hours.
- It is often approached as a stepping stone between Olympic distance and full long-distance racing.
Getting started
- 1Develop consistent endurance in swimming, cycling, and running before combining them over longer sessions.
- 2Many athletes complete shorter formats such as sprint and Olympic distance first.
- 3Review the specific event's course profile and cut-off details, since these vary between races.
Other Triathlon disciplines
The forms of Triathlon sit alongside each other — explore the rest.
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Techniques
- Freestyle StrokeThe fastest swimming stroke, using alternating overhead arm pulls, a flutter kick and rhythmic side breathing.
- Cycling CadenceThe technique of pedalling at a smooth, steady rhythm and choosing a gear that keeps the legs turning efficiently.
- Running FormThe efficient posture and stride mechanics of distance running, keeping the body relaxed and the cadence smooth.
Playing surfaces
- WaterThe medium for aquatic sport — pool or open water that supports the body with buoyancy and resists movement with drag rather than giving footing.
- Road (Tarmac / Asphalt)Paved tarmac or asphalt: a firm, smooth, predictable surface that rewards steady pace and rhythm — the ground for road running, cycling and race-walking.
- GravelLoose crushed stone over a firm base — an unpaved middle ground between smooth road and rough trail, ridden and run for variable grip and steady pace.
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- 2026-07-09
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