Running: how sprinting boosts the exercises that benefit heart and brain health

Exerchines. Bear this term in mind. These are proteins and metabolites released into the bloodstream after exercise and may be among the key mediators of the benefits associated with regular physical activity, as they are released by the body in response to exercise. They originate from tissues such as muscles, the heart, the liver, adipose tissue and the brain, and enable the various organs to communicate with one another when we move. This reduces inflammation, improves sugar and lipid metabolism, and helps to better protect the heart and brain. But if you really want to make the most of their health benefits, remember that it’s not just how hard you work out that matters, but also the speed you reach and the intensity of the effort. With just three minutes of sprinting – thanks to exerines and other factors – you can trigger a dramatic molecular response, leading to beneficial effects on metabolic health and biological ageing.

The advice to adopt a Usain Bolt-style running strategy – obviously for those physically capable of doing so – comes from research carried out by experts at Rockefeller University, published in Cell Reports Medicine and coordinated by Luke Olsen. The study clearly shows that, at the molecular level, three minutes of sprinting can produce a very different (and certainly more positive) molecular response than that observed after 90 minutes of moderate exercise.

Scientists compared the body’s response to exercise carried out at different intensities. They found that a series of six 30-second sprints at maximum speed alters the levels of certain proteins in the blood immediately after exercise to a far greater extent than slow cycling or a moderate one-and-a-half-hour run on a treadmill. Not only that: the response of fat cells also appears to be different. Blood tests carried out after a series of sprints revealed changes in the way adipocytes process nutrients, react to hormonal stimuli and perceive the body’s need for nutrients. With moderate exercise, the acute response appears much less significant: in particular, fat cells following a bike ride showed minimal variations in their activity, and it was only a few hours after the end of the session that there was an increase in fatty acids and proteins of hepatic origin, associated with the demands of endurance exercise.

The study shows that repeated sprints can alter more than 200 metabolites and rapidly increase the levels of proteins involved in angiogenesis – that is, the development of blood vessels – tissue remodelling and hormonal signalling, with positive effects on metabolism and biological ageing. To reach this conclusion, exercise responses were compared with health data from over 53,000 participants in the UK Biobank. It should be noted that many of these proteins were found to be associated with a lower risk of cardiovascular and metabolic diseases such as obesity, type 2 diabetes and others. Of the 33 proteins associated with a lower risk, 32 were altered by sprinting, whilst only 3 were affected by moderate exercise. As if that were not enough, more than a quarter of these proteins were also linked to slower biological ageing. In short: even just a few minutes of intense exercise can trigger a significant molecular response that persists over time.

The findings suggest that exercise intensity can have a significant impact on the proteins and metabolites released into the bloodstream and, consequently, on the way tissues throughout the body respond. “It is well known that different exercise intensities stimulate distinct adaptations throughout the body,” commented Olsen in a university press release. “However, the molecular mechanisms linking these intensity-dependent adaptations have remained largely unknown. Our work suggests that ‘exerchines’ – proteins and metabolites released into the bloodstream after exercise – are highly sensitive to exercise intensity and may be the key mediators of the health benefits derived from short bouts of intense physical exercise.”