Heart attack? No, it's just a spinning class

Spinning, a really intense form of indoor cycling that brings sweat to the brow and sometimes stars to the eyes, could also bring heart attack biomarkers to the bloodstream, according to Scandinavian researchers.

Troponin T, which is used as a cardiac biomarker for heart muscle damage in people with chest pain, is measured with a blood test. It's known that longer periods of exercise, such as marathons and triathlons, can increase troponin T levels. To find out whether shorter periods of exercise--such as an hour of spinning--could have a similar effect, the researchers measured cardiac biomarkers in 10 healthy people before a spinning session, and then one hour and 24 hours later. The levels doubled one hour after the session, and, in two people, the levels were around those usually used to indicate a heart attack.

"Levels returned to normal in everyone in the study 24 hours after the spinning session," says Smita Duttaroy, researcher at the Sahlgrenska Academy. "This is an important difference to patients who've had a heart attack, where levels of the markers can remain raised for several days afterwards."

Why is this important? Well, it doesn't seem to mean that spinning is damaging the heart (although sometimes, in a particularly intense session, it might feel like it is!) But it does mean that someone turning up at the emergency room after an exercise session, perhaps even with chest pains and with raised cardiac biomarker levels, may not necessarily be having a heart attack, and emergency room teams need to be aware.

"When somebody with chest pains comes for emergency treatment, and a blood test shows that the cardiac biomarkers are rising, it's important to recognize that this kind of increase can also occur in healthy people after a normal exercise session," Duttaroy concluded.

- read the press release
- see the abstract in the Scandinavian Cardiovascular Journal