How to Lift Weights Without Messing Up Your Runs

There’s a fine line between strength gains and excessive aches and pain.

You already know that lower-body strength-training can make you faster, but damn if time in the squat rack doesn’t trash your legs for tomorrow’s run. If you’ve ever rationalised skipping it to prep for the next day’s mileage, you may have a point. According to a recent review of 132 studies, it takes a full day or two more to recover from resistance training than it does a high-intensity run.

That doesn’t mean bail on strength work – just game it. Research shows that properly scheduling resistance training can lop seconds – even minutes – off your PB.

To get it right, you need to understand how your body reacts to moving heavy stuff. Picture pushing a hand truck 15 metres. Pretty easy. That’s running, and your body is the hand truck – it moves its own weight rather effortlessly. Now slide the hand truck under a fridge and push it just one metre. A lot more difficult. That’s mechanical loading; it’s why 10 heavy squats hurt more than 1000 foot strikes.

The reason strength training makes you faster is because it lowers the amount of energy required to hit a certain pace, explains Dr Kenji Doma, a sports and exercise scientist at James Cook University in Queensland, Australia, and author of the review. Your brain alters its neural recruitment pattern, calling up the most fatigue-resistant muscle fibres so you exert less energy.

The key to balancing both activities is timing. You don’t want to run at 80 per cent of your max effort right after heavy lifting, because there’s a lot more mechanical load being applied to your neuromuscular system, so your muscles fatigue more than they would in a typical running session, says Doma. Simply put, you won’t be ready to perform at the same level if you run the next day. Proof: researchers put runners who were experiencing delayed-onset muscle soreness (DOMS) after resistance-training on a 3K time trial. They found that, on average, the runners ran nine per cent slower and were at greater risk of injury due to muscle fatigue causing poor running form.

The ideal strength schedule, Doma says, is to start the week with low weight and intensity to avoid shocking the body. Then prioritise. runners should only strength-train twice a week, to ensure full recovery before a tough run, he says. Last, realise it’s okay to run on sore legs. If they feel tired, Doma recommends moving at 70 per cent or less of your max effort (a seven out of 10 rate of perceived exertion).

Want to put everything into a real-life training week? Your wish is Doma’s command.


Day 1
Light resistance training with a focus on upper body

Day 2
Tempo run (run at an eight out of 10 effort for approximately 20 minutes)

Day 3
Easy run, heavy resistance training with a focus on lower body

Day 4

Day 5
Tempo run

Day 6
Easy run

Day 7
Long run

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