Sports Drinks on the Edge of a New Era

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

“…The addition of a novel blend of alginate and pectin to sports drinks is proposed to form a hydrogel upon contact with stomach acid, encapsulating the CHO and enhancing gastric emptying rates to facilitate higher CHO oxidation rates during exercise (Sutehall, 2018). Our data do not support this proposition.…”

“…Innovations in CHO provision have seen the addition of pectin and sodium-alginate to traditional multiple transportable CHO beverages. Upon exposure to the low pH environment of the stomach the pectin-alginate polysaccharides encapsulate CHO within a hydrogel, which theoretically allows for CHO passage into the duodenum without activation of glucose receptors (Sutehall et al 2018). It has been speculated that hydrogel formulations increase gastric emptying rates during exercise, enhance absorption of oxidizable CHO, reduce the incidence and severity of gastrointestinal symptoms, and allow provision of CHO in concentrations that far exceed what can typically be tolerated using commercially available sports drinks (Sutehall et al 2018).…”

“…Upon exposure to the low pH environment of the stomach the pectin-alginate polysaccharides encapsulate CHO within a hydrogel, which theoretically allows for CHO passage into the duodenum without activation of glucose receptors (Sutehall et al 2018). It has been speculated that hydrogel formulations increase gastric emptying rates during exercise, enhance absorption of oxidizable CHO, reduce the incidence and severity of gastrointestinal symptoms, and allow provision of CHO in concentrations that far exceed what can typically be tolerated using commercially available sports drinks (Sutehall et al 2018). However, when pectin-alginate CHO drinks have been compared to traditional glucose(polymer) beverages, no differences have been shown in whole body substrate oxidation, blood glucose availability, or GI symptoms during either 90 or 180 minutes of treadmill running at 60% VO2max (McCubbin et al 2019;Barber et al 2020; both 90g .…”

Carbohydrate Hydrogel Products Do Not Improve Performance or Gastrointestinal Distress During Moderate-Intensity Endurance Exercise

“…Enhanced rates of gastric emptying could deliver this "hydrogel" to the small intestine where it dissolves in the higher pH environment for absorption, leading to reduced gut discomfort, enhanced muscle CHO delivery, and performance benefits (Figure 1). Indeed, according to testimonials, the commercial product has been quickly adopted by elite athletes (Sutehall et al, 2018) and publicized in sporting successes including the 1:59 marathon project, leading to marketing claims that it is the "world's fastest sports fuel" (Maurten, 2020). Noting that this has largely occurred in the absence of scientific validation of these claims, we undertook a review of newly published investigations of hydrogel CHO to determine whether they achieve better GI characteristics, substrate delivery, and performance effects under exercise conditions than traditional sports drinks and gels.…”

Alginate and HM-pectin in sports-drink give rise to intra-gastric gelation in vivo

“…9 Furthermore, a field study on elite long-distance runners reported high tolerability of an alginate containing drink with 30 wt% of CHO when used in individual training programs. 11 The effect of adding polysaccharides, such as alginates, to food or drinks, on uptake of CHO in vivo is not clear. While some studies report reduced gastric emptying rate, increased feelings of fullness [12][13][14][15][16] and attenuated peak glucose and insulin response 17,18 upon addition of polysaccharides to solid foods or drinks, others report absence of any effect of added fibers.…”