Effect of prior exercise on eccentric exercise-induced neutrophilia and enzyme release

Purpose: The purpose of this study was to determine the effects of prior ex ercise on:changes in circulating neutrophils, neutrophil activation, and my ocellular enzymes following a standardized bout of eccentric exercise. Meth ods: Twenty-four male volunteers were randomized into three groups (N = 8). Group C performed 10 sets of 10 eccentric Contractions of the quadriceps m uscles with both legs (100% of the concentric 1RM). Group D and Group F exe rcised for 2 h at 56% (V)over dot O-2max on a cycle ergometer followed by a similar bout of eccentric contractions. Group F also received 7.5 mL.kg(-1 ) of a carbohydrate-electrolyte beverage every 30 min during the submaximal exercise, whereas group D received no fluid. Results: Body weight remained unchanged in groups C and F and decreased in group D by 1.56 +/- 0.34 kg. Ultrastructural Z-Band damage increased three-fold following exercise and r emained elevated 3 d after exercise but was not different among groups. Cir culating neutrophils were elevated more in group D compared with those in g roup C immediately after the exercise or rest period, and this difference p ersisted 3 h after the eccentric exercise. Serum lactoferrin concentrations increased 3.3-fold after exercise in all groups (P < 0.01). Creatine kinas e levels (CK) rose in all subjects, with subjects in Group F and D having a significantly greater rise in CK after exercise compared with those in gro up C. Conclusions: These data indicate that submaximal exercise followed by a bout of eccentric exercise results in similar amounts of myofibrillar in jury with a larger neutrophil response and CK release.