NEUTROPHILIA AND CREATINE KINASE RELEASE FOLLOWING ECCENTRIC EXERCISE ARE INCREASED BY PRIOR EXERCISE 418

Abstract

To determine the effects of prior exercise/hypohydration on the rise in circulating neutrophils and myocellular enzymes following eccentric exercise, male volunteers were randomized into three groups (n=8 per group). Trial C performed 10 sets of 10 eccentric contractions of the quadriceps muscles with both legs (100% of the concentric 1RM). Trial D and Trial F exercised for 2 h at 56% VO2max on a cycle ergometer followed by the eccentric contractions. Trial F also received 7.5 ml·kg-1 of a carbohydrate-electrolyte beverage every 30 min during the submaximal exercise. Circulating neutrophils increased more in Trial D (Δ = 5,136 ± 1,598 counts/mm3) compared to Trial F (Δ = 1,733 ± 511 counts/mm3) and Trial C (Δ = 774 ± 257 counts/mm3) immediately after the 2 h submaximal exercise bout (P<0.04). The change in neutrophils at 3 h post eccentric exercise was also significantly different between Trial D (Δ = 4,868 ± 806 counts/mm3) and Trial C (Δ = 2,162 ± 665 counts/mm3) (P<0.01). Creatine kinase levels (CK) rose in all subjects with subjects in Trial F and D having a significantly greater rise in CK after exercise compared to Trial C. CK levels at 24 h (peak) correlated with circulating neutrophil counts 3 h after exercise (R = 0.474, P < 0.001). These data suggest that prior exercise may amplify the inflammatory response following eccentric exercise.