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

Med Sci Sports Exerc. 2000 Feb;32(2):359-64. doi: 10.1097/00005768-200002000-00015.

Abstract

Purpose: The purpose of this study was to determine the effects of prior exercise on changes in circulating neutrophils, neutrophil activation, and myocellular enzymes following a standardized bout of eccentric exercise.

Methods: Twenty-four male volunteers were randomized into three groups (N = 8). Group C performed 10 sets of 10 eccentric contractions of the quadriceps muscles with both legs (100% of the concentric IRM). Group D and Group F exercised for 2 h at 56%VO2max on a cycle ergometer followed by a similar bout of eccentric contractions. Group F also received 7.5 mL x 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 remained elevated 3 d after exercise but was not different among groups. Circulating neutrophils were elevated more in group D compared with those in group C immediately after the exercise or rest period, and this difference persisted 3 h after the eccentric exercise. Serum lactoferrin concentrations increased 3.3-fold after exercise in all groups (P < 0.01). Creatine kinase 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 group C.

Conclusions: These data indicate that submaximal exercise followed by a bout of eccentric exercise results in similar amounts of myofibrillar injury with a larger neutrophil response and CK release.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Body Weight
  • Creatine Kinase / metabolism*
  • Exercise / physiology*
  • Humans
  • Male
  • Muscle Contraction / physiology
  • Muscle, Skeletal / injuries
  • Myofibrils / physiology*
  • Myofibrils / ultrastructure
  • Neutrophils / physiology*

Substances

  • Creatine Kinase