What strength does for an endurance athlete
- Better economy: the same pace or power for less energy, in both running and cycling (Rønnestad and Mujika, 2014).
- Better performance: a systematic review found that strength training improved time-trial performance and economy in competitive endurance athletes (Beattie et al., 2014).
- No hidden cost: a 2022 meta-analysis of 43 studies found that combining endurance and strength training did not reduce gains in maximal strength or muscle size (Schumann et al., 2022).
The research is strongest for running and cycling. We found no comparable evidence for swimming performance, so this guide makes no claims about it.
Heavy, short and few: the session
- A squat or leg press: 3 to 4 sets of 4 to 6 reps, heavy but with a rep or two in reserve.
- A hinge: Romanian deadlift or hip thrust, 3 sets of 5 to 8.
- A single-leg exercise: Bulgarian split squat or step-ups, 2 or 3 sets of 6 to 8 per leg.
- Calf raises, 3 sets of 8 to 12, slow on the way down.
- Jumps: 3 to 5 sets of 5 box jumps or bounds, fresh, at the start or between lifts.
- Optional for the swim: a pull-up or lat pulldown and a row, 2 or 3 sets each.
Heavy, low-rep sets build strength without much muscle growth or fatigue, which is what an endurance athlete wants. High-rep circuits feel like hard work but add endurance you already train every day.
Through the season
| Phase | Sessions | Focus |
|---|---|---|
| Off-season | 2 a week | Build strength: the heaviest weeks of the year |
| Base and build | 2 a week | Keep the weights, cut a set if training load climbs |
| Race season | 1 a week | Short and heavy, to keep what you built |
| Last 7 to 10 days | None or 1 light | Arrive fresh |
Put strength on an easy day or after an easy session, never the day before your key run or ride of the week.
Fitting it into a triathlon week
Swim, bike and run already fill most weeks, so pair strength with an easy session rather than giving it a day of its own. A good pattern is lifting after an easy swim or a short easy ride, with at least a few hours, or ideally a day, before your next hard run or bike.
If something has to give in a heavy week, cut the volume of the gym session first: fewer sets, the same weights. A small dose is enough to hold strength: one short, heavy session a week.