Running a marathon can actually improve damage in the knees of middle-aged adults, according to a new study.

As part of research led by Dr Alister Hart of University College London and the Royal National Orthopaedic Hospital, and conducted in part by London Marathon Medical Director Professor Sanjay Sharma, 82 healthy adults underwent MRI scans on both knees six months before and two weeks after their first marathon.

MRI scans before training and running the London Marathon showed signs of damage to key structures in the knees of the majority of the 82 participants in the study.

But after the marathon, the 71 participants who completed the training and the event itself saw a reduction in the damage sustained to a number of essential components of the knee, including cartilage.

However, there was also evidence of some wear and tear to other parts of the knee which are put under stress during running.

Read more about the study at the Running For Science website.