Consuming carbohydrates (CHO) during prolonged exercise is a well-established practice for maintaining performance, preserving glycogen stores, and delaying fatigue. However, the way these carbohydrates are consumed —whether in gels, drinks, or diluted with water—can influence not only absorption but also gastrointestinal comfort, especially during long-duration activities.
A study published by Hearris et al. (2022) in the Journal of Applied Physiology investigated precisely this: the effects of consuming liquid carbohydrates enriched with sodium alginate (a substance that forms a gel in the stomach) on performance, molecular activation, and muscle morphological aspects.
What the study evaluated
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Participants consumed a beverage containing glucose and fructose , with or without the addition of sodium alginate .
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The idea behind alginate was to form a gel matrix in the stomach and, theoretically, modulate the release of carbohydrates in the intestine, which could improve gastrointestinal tolerance.
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Variables such as the following were analyzed:
• time until exhaustion,
• metabolic signaling (AMPK, p53),
• Morphology of intramuscular lipid droplets .
Key results
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Performance : Carbohydrate intake during exercise increased time to exhaustion, as expected. However, there was no additional benefit from the use of alginate .
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At the molecular level : no differences were observed in AMPK or p53 activation, nor were there any relevant changes in the structure of the lipid droplets .
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Method of administration : although the study focused on a drink with carbohydrates + alginate, it indirectly contributes to the discussion about the effectiveness of carbohydrate intake in liquid form , which includes consuming gel diluted in water .
What does this indicate?
Ingesting carbohydrates in liquid form is effective for providing energy during prolonged exercise, especially when combined with glucose and fructose, which utilize distinct transporters in the intestine and allow for higher absorption rates (up to ~90g/h). The use of additives such as alginate can modify the texture and intestinal release, but the performance benefits appear limited.
On the other hand, diluting the gel in water (a common practice among endurance athletes) can replicate many of the physiological effects observed when ingesting carbohydrate-rich drinks , with the added benefit of making consumption easier and reducing gastrointestinal discomfort, without compromising energy delivery.
Reference
Hearris, M.A., et al. (2022). The effect of carbohydrate-alginate ingestion on exercise capacity and intramuscular lipid droplet morphology and molecular signaling in human skeletal muscle. Journal of Applied Physiology
