Sugar before exercise, but not after the second breath in McArdle’s disease

A Dutch-Danish team conducted a randomised, double-blind, placebo-controlled crossover study involving nine patients with McArdle’s disease, or type V glycogenosis:

• ingestion, 10 minutes before the start of a 60-minute submaximal exercise test on an ergocycle, of a sweetened sports drink (in this case Faxe Kondi©) did result in a significant improvement in exercise tolerance, as measured by a smaller increase in heart rate and perceived exertion (Borg scale), compared with ingestion of a zero-calorie version of the same drink (placebo);
• heart rate and perceived exertion, on the other hand, did not differ between the two drinks ingested repeatedly during exercise, after the second wind phenomenon.

These results could help to reduce excessive carbohydrate intake and the risk of overweight and insulin resistance.

 

Repeated oral sucrose dosing after the second wind is unnecessary in patients with McArdle disease: Results from a randomized, placebo-controlled, double-blind, cross-over study. J Løkken N, Khawajazada T, Slipsager A et al. J Inherit Metab Dis. 2023 Jul 11.