Both exercise and a ketogenic (low-carbohydrate) diet favour glycogen depletion and increase ammonemia, which can impair physical performance. A study suggests that caffeine intake reduces elevated ammonemia that occurs during exercise. The study findings were published in the journal Nutrition on June 2, 2021.
Ammonia production is widely reported to increase during exercise and maybe a deleterious metabolite that promotes fatigue. Hyperammonaemia in response to exercise can be reduced through supplementation with either amino acids or combined keto analogues and amino acids (KAAA). Previous experimental studies have shown that acute use of caffeine supplementation reduces the increase in ammonemia caused by exercise. Therefore, Dr Eduardo Prado and his team conducted a study and evaluated the effect of xanthine on ammonemia in cyclists who were placed on a ketogenic diet and engaged in prolonged exercise.
In this study, the researchers included 14 male cyclists who followed a ketogenic diet for 2 d before and during the study. The cyclists were randomly assigned to either the caffeine- (CEx; n = 7) or placebo-supplemented (LEx; n = 7) group. The researchers collected and assessed the blood samples that were obtained during cycling and the recovery periods.
Key findings of the study:
Upon analysis, the researchers found that the CEx group showed a significant decrease (up to 25%) in blood ammonia at 60, 90, and 120 min after beginning exercise compared with the LEx group.
They observed a higher concentration of apparent blood urea in the LEx group than in the CEx group at 60 to 90 min of exercise (~10%).
They further found a significant increase in blood glucose levels at 30 min of exercise (~28%), and an increase in blood lactate levels during the first 30 to 60 min of exercise (~80%) in the CEx group.
The authors concluded, "Herein, we showed that when using a ketogenic diet to promote metabolic stress, acute caffeine supplementation can diminish the increase in ammonemia caused by endurance exercise in humans. We suggest that caffeine may decrease systemic ammonia by increasing glucose availability".
For further information:
https://doi.org/10.1016/j.nut.2021.111377