Is Running A Marathon Even Good For You?

Medical comment provided by Dr Donald Grant, GP and Senior Clinical Advisor at The Independent Pharmacy.

It’s a tough feat, even for tough feet: the 42.2km course of a standard marathon is a challenge many runners aspire to beat.

More and more of us are reaching the impressive milestone. 2026′s Brighton Marathon, for instance, saw a record-breaking 14,000 finishers.

Generally, being able to complete the race is seen as a marker of amazing health. Certainly, exercise is great for us, and runners can be expected to live as many as 12 years longer than less active people.

But given that ultra-endurance running has been associated with GI issues, and that tendinopathy, stress fractures, and even a higher risk of kidney and heart issues can hit on race day, we asked GP Dr Donald Grant to share whether they’re overall good or bad for our health.

Sure, the day itself can be tough – “The marathon itself places a significant amount of stress on the body, particularly on the heart, joints and muscles, and it’s not uncommon to see temporary inflammation, fatigue or minor injuries following the event”.

That’s especially true if you haven’t prepared well for the event. But the race is only one session in what is usually a multi-week programme.

“Many of the long-term health benefits actually stem from the training element, where continuous exercise helps improve cardiovascular well-being, strengthen muscles and support mental well-being,” said Dr Grant.

“For most people, these benefits will outweigh the short-term strain of the event itself, provided they train appropriately.

Sticking to a well-organised endurance training plan can “strengthen the heart and make it more efficient, reducing blood pressure.

“These adaptations are linked to a reduced risk of chronic conditions such as heart disease, stroke, and type 2 diabetes.”

So, while “The intense and repetitive strain placed on the body, particularly the joints, muscles, and connective tissues, can increase the likelihood of overuse injuries such as tendonitis and knee problems,” in general, “Running a marathon can be very good for your health when approached responsibly, but it can be harmful if undertaken without proper preparation and care.

“The difference lies in how well the demands of training and racing are balanced with recovery and overall lifestyle.”

Of course, you definitely don’t have to run a marathon to see health benefits.

Some research has suggested that the Goldilocks zone for maximum longevity is about two and a half hours of running per week (for reference, the average marathon finish time for UK women is about five hours, and obviously happens in one day).

“While running offers clear health benefits, these don’t necessarily continue to increase the longer or more intensely you train. Even moderate distance running is sufficient to improve cardiovascular fitness and overall well-being,” Dr Grant said.

“With extreme endurance events such as marathons, it could be said that benefits plateau and the risks of factors such as overuse injuries or fatigue may increase. It’s all about finding a balance that works for you.”