How to Add Strength Training to Your Running Plan (Without Ruining Your Legs)

There’s a persistent rumour in the running world: lift weights and your legs will turn to concrete. The truth? Done right, strength training doesn’t wreck your running—it supercharges it. The trick is in timing, intensity, and purpose, not in avoiding the rack altogether.

Why runners need strength training

Research consistently shows runners who lift are less injured, more economical, and faster over distance.
Stronger legs mean better ground reaction control, improved stride efficiency, and resilience when fatigue sets in. Think of it as bullet-proofing your chassis, not bulking it.

When to lift

The biggest mistake is hammering squats the day before speed work. Schedule your heavy sessions after quality runs, or pair them with an easy run day so the following 24 hours can be recovery-focused.
A simple rhythm:

• Mon – Speed or interval run

• Tue – Strength (lower-body emphasis)

• Thu – Tempo or mid-long run

• Fri – Mobility / upper-body strength

• Sun – Long run

That spacing gives 48 hours between your hardest leg demands—enough to adapt, not collapse.

How to lift

Focus on movement quality and intent rather than volume. Two to three sessions per week are plenty.

Core lifts: squat, deadlift, split squat, hip thrust, calf raise
Accessory work: single-leg balance, hamstring curls, glute med work, trunk rotation

Aim for 3–5 sets of 3–8 reps at controlled tempo. You want power and control—not “pump till failure.”

How to avoid the ‘dead-leg’ trap

• Keep heavy sessions at least two days before races or key runs.

• Prioritise sleep and carbs after gym days—recovery fuel, not restriction.

• Deload every 4–6 weeks: reduce volume, keep intensity.

• Use RPE (Rate of Perceived Exertion) instead of fixed loads when mileage spikes.