The effects of isomaltulose ingestion on gastric parameters and cycling performance in young men

Abstract

Background/Objective Isomaltulose is a disaccharide with a low glycaemic index and plays a role in maintaining postprandial glucose. The maintenance of glucose availability during prolonged exercise has been shown to enhance exercise performance. The present study compared the effects of pre-exercise isomaltulose versus maltodextrin ingestion on gastric parameters and cycling performance in young men. Methods Fourteen young men (mean ± S.D., age 23 ± 2 years) performed 60 min of continuous cycling at 75% of maximum heart rate followed by a 15-min exercise performance test while ingesting a 500-mL of water containing 100 mg of 13 C-sodium acetate with either 50 g of isomaltulose or 50 g of maltodextrin. Gastrointestinal discomfort was assessed periodically using an 11-point visual analogue scale throughout the study. The gastric emptying rate was evaluated periodically with the 13 C-sodium acetate breath test. For the exercise performance test, participants were instructed to pedal a cycle ergometer, exerting as much effort as possible at a self-selected pace. Results Plasma glucose and insulin concentrations measured at 30 min after ingestion were lower in the isomaltulose trial than in the maltodextrin trial. There were no differences in mean power output during the exercise performance test, gastric emptying rate or the subjective feelings of gastrointestinal discomfort between both trials. Conclusion Under the current exercise protocol, pre-exercise ingestion of isomaltulose compared with maltodextrin provided no additional benefit relative to gastric emptying or aerobic exercise performance. Both isomaltulose and maltodextrin ingestion did not influence gastrointestinal distress during 60 min of cycling and performance test.

Metabolic, hormonal and performance effects of isomaltulose ingestion before prolonged aerobic exercise: a double-blind, randomised, cross-over trial

“…Similarly, a greater amount of isomaltulose ingestion may also be necessary to acquire performance benefits. In the study by König et al (2016) 75 g of isomaltulose ingestion resulted in an increased power output during a 16 km time trial performance [13], conversely our study along with others in cyclists and soccer players [14,19,22] found no differences in performance outcomes.…”

“…Testing was carried out in the morning and laboratory visits were separated by at least 72 h. Participants reported to the lab after an overnight fast and were provided with 50 g of either maltodextrin (100% Maltodextrin Carbs, Myprotein, Cheshire, UK), isomaltulose (Risulose, Evonik Creavis GmbH, Marl, Germany) or glucose (100% Glucose Carbs, Myprotein, Cheshire, UK) in 400 ml of water. This quantity was chosen according to recommendations previously outlined, showing that 50 g of isomaltulose was well gastrointestinally tolerated and did not alter gastric emptying rate [ 19 ], while larger amounts may reduce performance due to signs of gastrointestinal discomfort [ 12 ]. Similarly, during initial pilot testing in our lab, we found 50 g of isomaltulose to be well tolerated, while larger amounts led to strong symptoms of gastrointestinal discomfort and consequently to failing to completing the exercise session.…”

“…Oral administration of isomaltulose has previously been shown to result in lower postprandial blood glucose and insulin concentrations in healthy and type 2 diabetes mellitus (T2DM) patients [11,[15][16][17]. During exercise, insulin concentrations were shown to be lower following isomaltulose ingestion throughout a 150 min cycling trial [18] or not differ during 60 min of cycling [19] compared to sucrose or maltodextrin respectively. The associations of blood glucose, insulin and GIP secretion after isomaltulose ingestion have been studied in resting conditions [16,20], however to the best of our knowledge these kinetics have not yet been investigated in exercise settings.…”

“…The results have been inconclusive, possibly because the glycaemic index or load has previously been shown not to affect endurance performance or metabolic responses, when conditions were matched for carbohydrate and energy [ 21 ]. Nevertheless, when matched for carbohydrate intake, one study has found improved time trial performance after cycling for 90 min at 70% VO 2 max following isomaltulose ingestion [ 13 ], while others have found no difference in cycling and soccer specific exercise [ 14 , 19 , 22 ] or even impaired cycling performance [ 12 ]. In addition, due to the slow absorption rate in the small intestine, isomaltulose has been suggested to cause gastrointestinal discomfort when ingested during 2 h cycling at 60% Wmax [ 12 ], however other trials have produced contrasting results, when ≤50 g were ingested before cycling [ 19 ] or soccer specific exercise [ 22 ].…”

Rapid HPLC Method for Determination of Isomaltulose in the Presence of Glucose, Sucrose, and Maltodextrins in Dietary Supplements

“…Currently, isomaltulose is also widely used in fitness supplements for athletes as a long-term source of energy, as this molecule cannot be metabolically broken down (consumed) into glucose and fructose as quickly as sucrose. This has prompted ongoing clinical trials on isomaltulose in dietary supplements for physical performance [ 12 , 13 , 14 ]. In 2008, the FDA (Food and Drug Administration) added isomaltulose as a substance eligible for the health claim [ 15 ] and later the European Food Safety Authority (EFSA) also confirmed the positive health effect of isomaltulose [ 16 , 17 ].…”