You can have too much of a good thing when it comes to exercising
While exercise is important for a long and healthy life, ultramarathons may accelerate the ageing of cells in our blood. Athletes who ran 170 kilometres over mountainous terrain accumulated more age-related damage to their red blood cells than those who completed a shorter distance.
Long-distance running has been linked to health issues before, such as temporary suppression of the immune system and anaemia. But we only now have an understanding of what it does to red blood cells – which transport oxygen around the body – particularly when done outside on mountainous terrain.
Angelo D’Alessandro at the University of Colorado Anschutz and his colleagues analysed blood samples from 11 adults aged 36, on average, within a few hours before and after they ran a trail 40-kilometre race. They did the same for a separate group of 12 people of around the same age who competed in a 170-kilometre ultramarathon over similar terrain.
The researchers found that competing in either race seemed to cause the runners’ red blood cells to accumulate more damage from molecules known as reactive oxygen species, which are produced at higher levels when these cells need to deliver more oxygen around the body.
Running the ultramarathon, but not the shorter race, also seemed to cause their red blood cells to shift more rapidly from a disc shape to a more spherical one, which is typically seen when they age. This damage is probably due to exercise increasing inflammation and particularly strenuous activity pushing red blood cells more forcefully around the body.
What’s more, only the ultramarathon runners experienced a roughly 10 per cent drop in their red blood cell numbers after the race, but this isn’t necessarily a problem for their health. The researchers are now studying the red blood cells of ultramarathon runners a day after they have completed a race, in order to better understand how long these effects last. They also want future work to examine whether these changes affect runners’ performance.
Overall, while exercise is vital for good health, it’s important to be mindful of the potential effects of extreme endurance activities on the body, particularly on red blood cells. Further research will help us better understand the impact of ultramarathons on our long-term health and performance.
