Effect of prolonged exercise and carbohydrate on total neutrophil elastase content.
OBJECTIVE
The purpose of the present study was twofold: first, to assess the effect of prolonged intense exercise on total neutrophil elastase content in endurance-trained cyclists and to determine whether this is associated with postexercise falls in lipopolysaccharide (LPS)-stimulated neutrophil elastase release; and second, to determine the effect of carbohydrate (CHO) ingestion during exercise on these responses.


METHODS
In a randomized design, nine trained male cyclists cycled for 2 h at 75% VO(2max) on two occasions with either CHO (6.4%, i.e., 64 g x L-1) or placebo (PLA) beverage ingestion before (5 mL x kg-1), during (2 mL x kg-1), and after (5 mL x kg-1) the exercise. Venous blood samples were obtained at rest, immediately postexercise, and at 1 h postexercise.


RESULTS
After exercise, CHO ingestion was associated with a higher plasma glucose concentration (P < 0.05) and fewer numbers of circulating neutrophils compared with the PLA trial (P < 0.01). Neither exercise nor CHO ingestion affected total neutrophil elastase content, yet LPS-stimulated neutrophil elastase release fell postexercise by approximately 47% on the PLA trial (P < 0.01). Values did not change significantly from preexercise on the CHO trial.


CONCLUSIONS
These findings suggest that neither exercise nor CHO-beverage ingestion influences the total elastase content of neutrophils. Therefore, changes in neutrophil elastase content cannot account for the fall in LPS-stimulated neutrophil elastase release after prolonged intense exercise or for the blunting of this response with CHO ingestion.
Bishop
Nicolette C
NC
School of Sport and Exercise Sciences, Loughborough University, Loughborough, United Kingdom. N.C.Bishop@llboro.ac.uk
Walsh
Neil  P
N
Scanlon
Gabriella A
GA
D000284:Administration, Oral; D000328:Adult; D001642:Bicycling / Q000502:physiology*; D001786:Blood Glucose / Q000378:metabolism; D002241:Carbohydrates / Q000008:administration & dosage*; D015550:Cell Degranulation / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D019344:Lactic Acid / Q000097:blood; D007958:Leukocyte Count; D019272:Leukocyte Elastase / Q000096:biosynthesis / Q000097:blood*; D008070:Lipopolysaccharides / Q000378:metabolism; D008297:Male; D009504:Neutrophils / Q000201:enzymology*; D010101:Oxygen Consumption / Q000502:physiology; D010807:Physical Endurance / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology; D010953:Plasma Volume / Q000502:physiology
D001786:Blood Glucose; D002241:Carbohydrates; D008070:Lipopolysaccharides; D019344:Lactic Acid; D019272:Leukocyte Elastase; D006854:Hydrocortisone