Strength training for runners: two sessions a week is the whole game

New runners are told to run more. Fewer are told the thing that protects all that running: lift twice a week. The evidence here is unusually clean, and it matters most for beginners, who get hurt the most.

Start with economy — how much energy you burn at a given pace. Across controlled studies, eight to twelve weeks of resistance training improves running economy by roughly 4–5%. That means the same pace costs you less, so it feels easier and you can hold it longer. Explosive, plyometric-style work (think low hops and bounds) produces a similar gain — one study measured a 4.1% improvement at a brisk pace — and even simple isometric calf strengthening landed in the 4–7% range. The mechanism isn't mysterious: stronger, stiffer tendons and muscles return more energy with each stride.

The part beginners care about most is injury. In one cohort, runners who did resistance work at least three times a week had a 54% lower rate of running-related injuries. Targeted strengthening matters too: a group that neglected foot and ankle work got hurt 2.42 times as often as those who trained it, and six weeks of hip strengthening cleared up pain in runners with IT-band syndrome. Strength fixes the weak links that repetitive impact keeps finding.

Two worries usually stop new runners from lifting. First, "I'll get bulky and slow." You won't — most resistance-training studies show no change in body mass at all. You get stronger, not heavier. Second, "I won't know what to do." You don't need a complicated program. Effective loads run the full range from heavy (around 85% of a one-rep max for a few reps) to moderate (40–70%), so squats, lunges, step-ups, calf raises, and some hip and core work — two short sessions a week — covers it.

Keep it simple, keep it twice a week, and treat it as running insurance you actually cash in.

Source: Trowell et al. — Resistance Exercise for Improving Running Economy and Decreasing Injury Risk (PMC9319953)