The honest answer is two sessions a week. The useful answer is that it depends on where you are in a season, and that the mistake almost everyone makes is not lifting too much — it is stopping entirely the moment running gets serious.
Base phase: two to three sessions
When running volume is moderate and there is no race in sight, this is the time to actually get stronger. Two heavy sessions a week, three if your mileage is genuinely low. Rep ranges of four to six, long rests, focus on adding load.
Build phase: two sessions
Running volume and intensity are both climbing. Strength work holds at two sessions but stops chasing new maximums — the aim is to maintain what you built while the running does the heavy lifting for your race goal.
Peak phase: one to two sessions
This is where most runners quit the gym, and it is a mistake. Detraining strength takes only a few weeks, and arriving at a race having lost the thing that was protecting you from injury is a poor trade. Drop to one session if you must, keep it heavy, keep it short.
Taper: keep going, do less
Cut volume — fewer sets, fewer exercises — but keep the load heavy. A short, sharp session eight to ten days out, and something very light in the final week. Stopping cold tends to leave athletes feeling flat rather than fresh.
The mistake is rarely lifting too much. It is stopping entirely the moment running gets serious.
Where to put it in the week
The principle is polarisation: make hard days hard and easy days genuinely easy. That means strength work goes on a day that is already hard, not on a recovery day where it quietly turns an easy day into a moderate one.
- Best: after a quality run, same day.
- Acceptable: on its own, at least 24 hours from a key session.
- Avoid: the day before a long run or an interval session.
- Avoid: on your designated easy or rest day.
A workable week
- Monday — rest or easy run
- Tuesday — intervals, then strength
- Wednesday — easy run
- Thursday — easy run
- Friday — tempo, then strength
- Saturday — easy run or rest
- Sunday — long run
That is one template, not the template. The shape matters more than the specific days: two strength sessions, both attached to hard running days, with at least one properly easy day between them and the long run.
When to skip it
Skip a session if you are ill, if you are genuinely under-slept, or if a niggle is telling you something. Missing one session costs you nothing. Training through an injury costs you a season.
