Marathon Training Load: Avoiding the Classic Breakdowns

If you are running an autumn marathon, late August is where the block gets serious. The long runs are genuinely long, the weekly mileage is at or near its peak, and there are still enough weeks left that quitting feels unthinkable. It is also, reliably, when my phone starts ringing.

Marathon training injuries are rarely mysterious. In the overwhelming majority of cases I can trace them back to something specific in the training diary three to six weeks before the pain started. That is the useful part: if the cause is a decision, the prevention is also a decision.

Load, not weakness

The single most useful idea in running injury is that tissue has a tolerance, that tolerance moves, and it moves slowly. Bone, tendon and muscle all adapt to being loaded, but each adapts on its own timescale, and all of them are slower than your cardiovascular system.

That produces the classic marathon trap. By week eight you feel fit. You are fit. But feeling fit is a statement about your heart and lungs, not about the tendon at the back of your ankle, and it tempts you into exactly the sort of jump that causes trouble. Research consistently links rapid increases in training load with elevated injury risk, and every experienced coach I know builds their plan around that principle rather than around heroics.

The classic breakdown points

Achilles and calf. The most common casualty of adding speed work on top of high mileage. Stiffness for the first ten minutes of a run, warming up, then aching later. Tendons dislike sudden change more than they dislike hard work.

Front of the knee. Aching around the kneecap, worse on descents, stairs and after sitting. Often shows up when hills or long runs increase sharply.

Outside of the knee. A sharp, well-localised pain on the outer knee that appears at a predictable point in a run and forces you to stop. Typically linked to hip control and to a big jump in downhill or long-run volume.

Bone stress injuries. The one that ends marathons. Pain that is pinpoint over a bone, gets worse as the run goes on rather than warming up, hurts on hopping, and may ache at night. Shin, foot and hip are the usual sites. This needs assessment, not another week of hoping.

Plantar heel pain. Sharp on the first steps in the morning, easing with movement, then returning after a long run.

The three load errors behind most of them

The spike week. Somebody misses a fortnight through work or a cold, then rejoins the plan where the plan says they should be. The plan does not know about the fortnight. Rejoin where your body left off, not where the schedule is.

Stacking intensity on top of volume. Adding tempo runs, intervals and hills in the same week that your long run steps up is two load increases at once. Change one variable at a time.

Skipping the down week. Adaptation happens during recovery, not during the session. A planned easier week every third or fourth week is not lost fitness, it is when the fitness actually gets built.

The load you are not counting

Two things influence injury risk more than most runners expect.

The first is sleep. It is the most powerful recovery tool available and the first thing people sacrifice when training hours rise.

The second is energy availability. Marathon training burns a great deal, and runners who under-fuel, deliberately or otherwise, are at meaningfully higher risk of bone stress injuries as well as fatigue, poor adaptation and hormonal disruption. This affects men and women. If your weight is drifting down during a heavy block, or your periods have become irregular or stopped, that warrants a conversation with your GP rather than being treated as a sign the training is going well.

What to do when a niggle appears

Mid-block, the instinct is to either ignore it or panic. Neither helps. I use a simple framework with runners.

Pain that stays at a mild level, does not make you limp, settles within 24 hours and is not getting worse week on week is usually something you can keep training around, with reduced volume and no speed work for a fortnight.

Pain that changes how you run, gets worse during a run, is still there the next morning, or is sharply localised over a bone means stop and get it assessed. That is not the end of your marathon. Most runners who get a niggle looked at in week two of it still make the start line. Most of those who wait until week eight do not.

Cross-training genuinely works here. Cycling, the pool, or a cross-trainer will preserve most of your aerobic fitness for two or three weeks while a tissue calms down. You will lose far less than you fear.

Red flags

Seek urgent medical assessment rather than physiotherapy if you develop chest pain, unusual breathlessness, palpitations or fainting during exercise; calf pain with swelling, warmth and redness that did not follow an injury; or sudden severe pain at the back of the ankle with difficulty pushing off, which can indicate an Achilles rupture.

The taper is part of the training

The final point, because it is the one people undermine. The taper is where the accumulated work becomes performance. Cutting volume substantially in the last two to three weeks while keeping some intensity is well supported, and it is also the period when a last-minute panic session causes an injury that all those months cannot survive. Trust the block you have done.

If something has started grumbling

The runners I work with across Liverpool and Merseyside usually want two things: an honest answer about whether the race is still on, and a plan that keeps as much training as safely possible. That is exactly what an assessment should give you. I offer home visits at £90 a session and online video consultations at £60, evenings Monday to Friday, plus Saturday and Sunday daytimes, and you do not need a GP referral. There is more about how I work with runners on my sports injury physiotherapy in Liverpool page and on the sports injury rehabilitation page.

If you are mid-block and something is not right, get it looked at this week rather than next month. Book at /portal/book or call me on +44 7443 357020.