Does chronic physical activity level modify the airway inflammatory response to an acute bout of exercise in the post-prandial period?

Recent studies have confirmed that a single high-fat meal (HFM) leads to increased airway inflammation. However exercise is a natural anti-inflammatory and may modify post-prandial airway inflammation. The post-prandial airway inflammatory response is likely to be modified by chronic physical activity (PA) level. PURPOSE: To investigate whether chronic PA modifies the airway inflammatory response to an acute bout of exercise in the post-prandial period in both insufficiently active and active subjects. METHODS: Thirty-nine non-asthmatic subjects (twenty active (ACT), 13M/7F) who exceeded PA guidelines (>150 min moderate-vigorous PA/week) and (nineteen insufficiently active (IN), 6M/13F) underwent an incremental treadmill test to exhaustion to determine VO2peak. Subjects were then randomized to a condition (COND), either remaining sedentary (CON) or exercising (EX) post-HFM. Exercise was performed at the heart rate corresponding to 60% VO2peak on a treadmill one-hour post-HFM (63% fat, 10kcal/kg bw). Blood lipids and exhaled nitric oxide (eNO: marker of airway inflammation) were measured at baseline, 2 h and 4 h post-HFM. Sputum differential cell counts were performed at baseline and 4 h post-HFM. RESULTS The mean eNO response for all groups increased at 2 h post-HFM (~6%) and returned to baseline by 4 h (p=0.03). There was a time*COND interaction (p=0.04), where EX had a greater eNO response at 4 hours compared to CON. Sputum neutrophils increased at 4 hours post-HFM (pThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author