Effects of Reduced Carbohydrate Intake after Sprint Exercise on Breath Acetone Level

Abstract

Assessment of breath acetone level may be an alternative procedure to evaluate change in fat metabolism. The purpose of the present study was to investigate the effect of insufficient carbohydrate (CHO) intake after sprint exercise on breath acetone level during post-exercise. Nine subjects conducted two trials, consisting of either reduced CHO trial (LOW trial) or normal CHO trial (NOR trial). In each trial, subjects visited to laboratory at 7:30 following an overnight fast to assess baseline breath acetone level. They commenced repeated sprint exercise from 17:00. After exercise, isoenergetic meals with different doses of CHO (LOW trial; 18% for CHO, 27% for protein, 55% for fat, NOR trial; 58% for CHO, 14% for protein, 28% for fat) were served. Breath acetone level was also monitored immediately before and after exercise, 1 h, 3 h, 4 h, and 15 h (on the following morning) after completing exercise. A significant higher breath acetone level was observed in LOW trial than in NOR trial 4 h after completion of exercise (NOR trial; 0.66 ppm, LOW trial; 0.9 ppm). However, breath acetone level did not differ on the following morning between two trials. Therefore, CHO intake following an exhaustive exercise affects breath acetone level during early phase of post-exercise.

How Metabolomics Provides Novel Insights on Celiac Disease and Gluten-Free Diet: A Narrative Review

“…Some of the selected studies assessed higher levels of ketogenic metabolites in U-CD than in HC ( Bertini et al, 2009 ; Di Cagno et al, 2009 ; Bernini et al, 2011 ; Upadhyay et al, 2020 ). Similarly, Bertini et al (2009) analyzed the same subjects pre- and post-GFD and observed an inverse tendency in serum levels of β-hydroxybutyric acid, which is a ketone body usually increased during the fasting phase as an alternative energy source for brain activity ( Ota et al, 2021 ). Hence, the significant decrease of β-hydroxybutyric acid ( Bertini et al, 2009 ) seems to indicate the return to a normal energy metabolism via carbohydrates instead of ketone bodies driven by GFD.…”