Marathon Training Injury Prevention: A Physio's Guide

Somewhere between 30-70% of marathon runners get injured badly enough during training to lose time off their plan, depending on which study you read and how "injury" is defined. That range is wide, but the pattern underneath it is consistent: the vast majority of these injuries are preventable, and they're almost never caused by "bad luck." They're caused by predictable training errors.

Why Marathon Injuries Happen

Running is a high-repetition, high-impact activity. Over a training block you'll take hundreds of thousands of ground contacts on the same joints, tendons, and muscles. Injury happens when the load placed on a tissue exceeds what it's currently prepared to handle — and "currently prepared" is the key phrase, because that capacity can be built up deliberately.

The most common culprits

• Doing too much, too soon. Increasing weekly mileage faster than your tissues can adapt is the single biggest driver of running injuries.
• Ignoring strength work. Runners who skip strength training are more prone to tendon and joint injuries, because running alone doesn't sufficiently load muscles through their full range in ways that build resilience.
• No deload weeks. Continuous mileage increases without periodic recovery blocks don't give tissues time to actually adapt.
• Ignoring early warning signs. Many runners push through nagging pain until it becomes a diagnosed injury, when a few days of modified training earlier would have resolved it.

The Injuries Physios See Most in Marathon Training

1. Runner's knee (patellofemoral pain). Often linked to hip and glute strength deficits, not just "knee problems."
2. Achilles tendinopathy. Usually a gradual overload issue, made worse by sudden increases in speed work or hill training.
3. Shin splints (medial tibial stress syndrome). Classic "too much, too soon" injury, especially in runners returning from a break.
4. IT band syndrome. Frequently tied to weak hip abductors and training volume spikes.
5. Plantar fasciitis. Linked to calf tightness, footwear changes, and rapid mileage increases.

Almost every one of these has the same root fix: build capacity ahead of demand, not after an injury forces you to.

How to Structure Training to Reduce Risk

1. Progress mileage gradually

A commonly cited guideline is capping weekly mileage increases at roughly 10%, though the right number depends on your training history and current fitness. The point isn't the exact percentage — it's building in a ceiling so ambition doesn't outrun tissue adaptation.

2. Strength train twice a week, minimum

Focus on the hips, glutes, and calves — the areas most linked to common running injuries — alongside general full-body strength work. This isn't about bulking up; it's about giving your tendons and joints more resilience under repeated load.

3. Build in deload weeks

Every 3-4 weeks, deliberately drop volume by 20-30%. This is where adaptation actually consolidates — the hard weeks create the stimulus, the easier weeks let your body catch up.

4. Respect early warning signs

Pain that's sharp, one-sided, or gets worse during a run (rather than warming up and easing) is worth addressing immediately, not "running through." A few modified sessions early is far cheaper than eight weeks off later.

5. Get a running-specific movement assessment

A lot of runners carry small asymmetries or strength imbalances they've never noticed because running doesn't obviously feel wrong — until it does. An assessment before a big training block can catch these early.

The Bottom Line

Marathon injuries aren't random — they're the predictable result of specific, identifiable training decisions. A plan that balances mileage progression, strength work, and recovery isn't just "nice to have," it's what actually gets you to the start line healthy.