Addition of pectin-alginate to a carbohydrate beverage does not maintain gastrointestinal barrier function during exercise in hot-humid conditions better than carbohydrate ingestion alone

Appl Physiol Nutr Metab. 2020 Oct;45(10):1145-1155. doi: 10.1139/apnm-2020-0118. Epub 2020 May 4.

Abstract

The objective of this study was to compare the effects of consuming a 16% maltodextrin+fructose+pectin-alginate (MAL+FRU+PEC+ALG) drink against a nutrient-matched maltodextrin+fructose (MAL+FRU) drink on enterocyte damage and gastrointestinal permeability after cycling in hot and humid conditions. Fourteen recreational cyclists (7 men) completed 3 experimental trials in a randomized placebo-controlled design. Participants cycled for 90 min (45% maximal aerobic capacity) and completed a 15-min time-trial in hot (32 °C) humid (70% relative humidity) conditions. Every 15 min, cyclists consumed 143 mL of either (i) water; (ii) MAL+FRU+PEC+ALG (90 g·h-1 CHO/16% w/v); or (iii) a ratio-matched MAL+FRU drink (90 g·h-1 CHO/16% w/v). Blood was sampled before and after exercise and gastrointestinal (GI) permeability, which was determined by serum measurements of intestinal fatty acid binding protein (I-FABP) and the percent ratio of lactulose (5 g) to rhamnose (2 g) recovered in postexercise urine. Compared with water, I-FABP decreased by 349 ± 67pg·mL-1 with MAL+FRU+PEC+ALG (p = 0.007) and by 427 ± 56 pg·mL-1 with MAL+FRU (p = 0.02). GI permeability was reduced in both the MAL+FRU+PEC+ALG (by 0.019 ± 0.01, p = 0.0003) and MAL+FRU (by 0.014 ± 0.01, p = 0.002) conditions relative to water. In conclusion, both CHO beverages attenuated GI barrier damage to a similar extent relative to water. No metabolic, cardiovascular, thermoregulatory, or performance differences were observed between the CHO beverages. Novelty Consumption of multiple-transportable CHO, with or without hydrogel properties, preserves GI barrier integrity and reduces enterocyte damage during prolonged cycling in hot-humid conditions.

Keywords: I-FABP; alginate; carbohydrate; chaleur; cycling; cyclisme; gastrointestinal symptoms; glucides; heat; hydrogel; symptômes gastro-intestinaux.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Alginates / administration & dosage*
  • Beverages*
  • Bicycling*
  • Dietary Carbohydrates / administration & dosage*
  • Enterocytes / drug effects
  • Female
  • Fructose / administration & dosage
  • Humans
  • Intestinal Absorption / drug effects*
  • Male
  • Pectins / administration & dosage*
  • Polysaccharides / administration & dosage
  • Temperature
  • Young Adult

Substances

  • Alginates
  • Dietary Carbohydrates
  • Polysaccharides
  • Fructose
  • maltodextrin
  • Pectins