Do antihistamines affect triathlon improvement?

Do antihistamines impair triathlon improvement? One study out of Ghent University suggests it’s a possibility…

Published: January 10, 2022 at 9:43 am

What is histamine?

Histamine is a substance in the body that responds to pollens, moulds, animal dander, insect bites and other allergens, however some people’s bodies go in overdrive and fuel uncomfortable allergic reactions, prompting the use of antihistamines.

What is hayfever?

Hayfever affects one in four people in the UK with the grass-pollen peak in June and July. It’s debilitating, leading to countless antihistamine purchases. Temporarily, they ease the symptoms.

But, says recent research out of Ghent University, they could be impacting your long-term adaptation to exercise.

Does histamine benefit training adaptations?

The team found that histamine receptors are activated during a consistent training programme, improving a range of cardiometabolic factors, from insulin sensitivity to aerobic capacity and blood-vessel health.

This discovery stemmed from 20 healthy men training three times a week for six weeks. One hour before each session, half the men received drugs that blocked the H1 and H2 histamine receptors while the other half took a placebo.

Do antihistamines reduce training adaptations?

The results showed that the histamine group enjoyed smaller improvements in the ability of mitochondria to generate power; impairment of insulin’s ability to shuttle glucose from the bloodstream into muscles; and had less capillary formation in their leg muscles.

Should I stop using antihistamines?

So, time to banish Clarityn to the back of the medical cabinet? Maybe not. The researchers used two antihistamine drugs rather than one so couldn’t offer conclusions on a sole capsule.

And the doses were significantly higher than your daily hayfever-easing drug. Still, it might be time to try that local honey…

Illustration: Daniel Seex