Effects of an acute bout of moderate intensity exercise on postprandial lipemia and airway inflammation

Abstract

Obesity and asthma often coexist in the same people. Both are characterized by the presence of low-grade systemic inflammation. A high-fat diet may contribute to concurrent development of both conditions by promoting a pro-inflammatory postprandial environment leading to a transient accumulation of blood lipids (postprandial lipemia; PPL) and acute airway inflammation. Previous results from our lab have shown an ~20% increase in airway inflammation two hours after consuming a high-fat meal (HFM) that was significantly associated with increased plasma triglycerides. While acute exercise has been shown to attenuate PPL, it is unknown whether these protective effects will translate to reduced airway inflammation after a high-fat meal. PURPOSE: To determine the effects of an acute bout of exercise on airway inflammation after a HFM. We tested the hypothesis that an acute bout of exercise 12 hours before a high-fat meal would protect against subsequent airway inflammation in healthy men and would be related to the decreased PPL and systemic inflammatory markers. METHODS: In a randomized cross-over study, 12 healthy college-aged men consumed a HFM (1g fat/1kg body weight) 12 hours following exercise (EX; 60 min at 60% VO2max) or without exercise (CON). Exhaled nitric oxide (eNO; measure of airway inflammation), blood lipid profiles (venous sample; total cholesterol, HDL, LDL, triglycerides, glucose), inflammatory markers (hsCRP, TNF-[alpha], IL-6) and pulmonary function tests (PFT) (forced expiratory volume in 1-s,forced vital capacity, forced expiratory flow at 25-75% of vital capacity) were measured pre-HFM, two hours, and four hours post-HFM. RESULTS: Baseline eNO was not different (p>0.05) between trials. eNO increased (p<0.05) post HFM at two hours in the both CON and EX conditions. eNO between trials was not different (p>0.05). Triglycerides were significantly increased two and four hours post HFM but were not different (p>0.05) between conditions. There was no relationship (p>0.05) between eNO and triglycerides or systemic inflammatory markers for any time point in either condition. Pulmonary function did not differ (p>0.05) between any condition. CONCLUSION: These results demonstrate that an acute bout of moderate intensity exercise 12 hours before a HFM does not attenuate postprandial airway inflammation or lipemia in healthy college-aged men.