The University of Stirling campus marks the half-way point of the inaugural Stirling Scottish Marathon.

Ahead of the event, expected to attract around 6,500 runners, we caught up with one of our resident sport science experts, Dr Angus Hunter, to explain what happens to the body when you take on a 26-mile run. Here’s Dr Hunter’s top five marathon insights.

You burn a day’s-worth of calories

Runners can expect to burn a day’s-worth of calories in the process of a marathon. This means your body rapidly depletes its fuel stores, which, if not replenished, can cause premature fatigue.

Anyone training for a marathon needs 40 to 60 additional grams of carbs per hour of exercise to help their performance. That’s why it’s so important to plan your nutrition in the run-up to the event.

Your muscles work incredibly hard

Evidence suggests that the quadriceps and calf muscles are worked the hardest during a marathon. Our bodies cope with the hard work through appropriate pacing – gained through experience – and adequate hydration to meet the body’s requirements. Keeping on top of this will help your legs propel you around the course.

Your pH drops

Over a marathon, your pH will generally drop throughout. If you start off fast, you build up acidity, and that will impair the electrical signals that run from your brain across to your muscles. So pace yourself – if you start off slow, you end up clearing more lactate than you can produce, and you won’t get an acidic build up.

You might “hit a wall”

The theory is that the point where your glycogen (carbohydrate) stores become depleted, it feels like “hitting a wall”. It’s something 40% competitors suffer from but it can be avoided with appropriate training.

It takes time to recover

Your body can take as long as two or three months to fully recover from running a marathon, depending on the intensity you sustained on the run.

One theory behind this is that your muscles have suffered low-frequency fatigue, which impairs the release of calcium – and you need calcium for your muscles to shorten – so be aware this will take a couple of months to normalise.

Our sport scientists know how it feels!

Enjoy your run – when you cross that finish line, you’ll be in no doubt it was worth all the hard work!