The effects of postexercise feeding on saliva antimicrobial proteins

• Published in: International journal of sport nutrition and exercise metabolism Vol. 22; no. 3; p. 184
• Main Authors: Costa, Ricardo J S, Fortes, Matthew B, Richardson, Katharine, Bilzon, James L J, Walsh, Neil P
• Format: Journal Article
• Language: English
• Published: United States 01.06.2012
• Subjects: Adult; alpha-Amylases - metabolism; Anti-Infective Agents; Biological Factors - metabolism; Diet; Dietary Carbohydrates - pharmacology; Dietary Proteins - pharmacology; Feeding Behavior - physiology; Humans; Immunoglobulin A - metabolism; Male; Muramidase - metabolism; Oxygen Consumption; Running - physiology; Saliva - metabolism; Saliva - physiology; Salivary Proteins and Peptides - metabolism; Young Adult
• ISSN: 1543-2742
• DOI: 10.1123/ijsnem.22.3.184

The purpose of this study was to determine the effects of a carbohydrate (CHO) and protein (PRO) drink consumed immediately after endurance exercise on saliva antimicrobial proteins known to be important for host defense. Eleven male runners ran for 2 hr at 75% VO2max on 2 occasions and immediately postexercise were provided, in randomized order, either a placebo solution (CON) or a CHO-PRO solution containing 1.2 g CHO/kg body mass (BM) and 0.4 g PRO/kg BM (CHO-PRO). The solutions were flavor and volume equivalent (12 ml/kg BM). Saliva flow rate, lysozyme, α-amylase, and secretory (S) IgA concentrations were determined from unstimulated saliva samples collected preexercise, immediately postexercise, and every 30 min until 180 min postexercise. CHO-PRO ingestion immediately postexercise resulted in a lower saliva flow rate than with CON at 30 and 60 min postexercise. Saliva lysozyme concentration increased immediately postexercise in both trials compared with preexercise (p< .05), and CHO-PRO ingestion immediately postexercise resulted in a higher saliva lysozyme concentration in the first hour of recovery than with CON (125% greater at 30 min, 94% greater at 60 min; p< .01). Saliva SIgA concentration decreased below preexercise concentrations 90-150 min postexercise (p< .001), with no effect of CHO-PRO. Saliva α-amylase activity was unaffected by exercise or CHO-PRO refeeding. CHO-PRO refeeding did not alter the secretion rates of any saliva variables during recovery. In conclusion, immediate refeeding with CHO-PRO evoked a greater saliva lysozyme concentration during the first hour of recovery after prolonged exercise than ingestion of placebo but had minimal impact on saliva α-amylase and SIgA responses.