Adaptation to eccentric exercise: neutrophils and E-selectin during early recovery

The purpose was to determine the responses of blood neutrophils and E-selectin concentrations during early recovery (<24hr) from 2 bouts of eccentric exercise. Subjects (N=9) completed 2 bouts of eccentric arm exercise using their non-dominant arm (Bout 1 and Bout 2) and 1 non-exercise control condition. The exercise bouts were separated by 4 weeks, and the control condition preceded bout 1. Neutrophil concentrations were significantly higher at 3, 6, and 9-hr post-exercise for Bout 1 relative to Bout 2 and control. No significant changes in blood E-selectin concentrations were observed. Isometric strength deficit was similar for Bout 1 and Bout 2 at 5 min and 3 hr post exercise and was significantly great for Bout 1 relative to Bout 2 at 6, 9, and 24-hr post-exercise. The adaptation to eccentric exercise is associated with a lower concentration of blood neutrophils during early recovery. The neutrophilia associated with novel eccentric arm exercise precedes secondary changes in isometric strength and is not associated with changes in the concentration of blood E-selectin.