The Effect of Nonspecific COX Inhibitors on Serum Chemistries during Ultradistance Running

Abstract

PURPOSE: To determine the effects of both ultradistance running and a nonspecific COX inhibitor on serum chemistries during a 160 km running race. METHODS: Twenty nine subjects (47.9+1.4 yrs) ingested 600 mg of ibuprofen the day before, and 1200 mg ibuprofen during a 160 km running race. Ibuprofen was taken every ∼4hrs in 200 mg doses. Control subjects (N=25, 46.8+2.1 yrs) avoided ingestion of ibuprofen before or during the race. Blood was drawn from the antecubital space on the day before the race and immediately post-race. Serum chemistry profiles were analyzed by a clinical laboratory. RESULTS: Subjects in the two groups did not differ by age, training volume, race experience, BMI, body fat, or finishing time (25.8+0.6 vs. 25.6+0.8 hr). Body weight did not change significantly from pre-race, mid-race (90 km), to post-race. Ultradistance running caused a significant decrease in pre- to post-race in serum sodium (p=0.006), potassium (p=0.001), chloride (p < 0.001), calcium (p < 0.001), albumin (p < 0.001), and globulin (p < 0.001). Increases were seen in creatine kinase (p < 0.001), creatinine (p < 0.001), blood urea nitrogen (p < 0.001), uric acid (p < 0.001), glucose (p < 0.001), aspartate aminotransferase (p < 0.001), and alanine aminotransferase (p < 0.001) as the result of the race. Ibuprofen ingestion caused a significant increase in only blood urea nitrogen (p=0.04), alanine aminotransferase (p=0.03), and aspartate aminotransferase (p=0.04), but not CPK (p=0.16). CONCLUSIONS: These data suggest that nonspecific COX inhibitors such as ibuprofen do not alter serum electrolytes during ultradistance running. However the stress of ultradistance running does cause significant changes in serum diagnostic chemistries, and the addition of ibuprofen may elevate markers of liver and muscle damage.