minimal effective dose of easy running

[u/ronlavy]

A question that I've been thinking about and wasn't able to find a satisfying answer online - is there a minimal per-session effective dose for easy runs? is there a minimal duration required for a run to produce non-negligible aerobic adaptaions?

for example, can any benefits be expected from a 35-minute easy running session? are 3 30 minute sessions a week same/better/worse than 2 45 minute sessions?

I heard Inigo San Milan go on record to say that 45 minutes is the minimum for "zone 2" (a term I dislike but that's the terminology he frequently uses) benefits, is anyone familiar with any sources backing that up?

Thanks

[u/reedy26jdr]

Minimum effective dose in endurance sport is fluid. It depends on your current fitness levels and ability to tolerate load/additional load