Effect of Galactose Ingestion Before and During Exercise on Substrate Oxidation, Postexercise Satiety, and Subsequent Energy Intake in Females.
OBJECTIVE
To examine the effects of consuming a galactose carbohydrate (CHO) drink on substrate oxidation, postexercise satiety, and subsequent energy intake.


METHODS
Nine recreationally active eumenorrheic females undertook 3 trials, each consisting of running for 60 minutes at 65% VO(2peak) followed immediately by a 90-minute rest period. Prior to (300 ml) and at 15-minute intervals during exercise (150 ml), participants consumed either a glucose (GLU: GI 89) or galactose (GAL: GI 20) drink, each of which contained 45 g of CHO, or an artificially sweetened placebo (PLA). Following the rest period, participants were provided with an ad libitum test lunch and asked to record food intake for the remainder of the day.


RESULTS
Plasma glucose was significantly greater throughout exercise and rest following the GLU trial compared with the GAL and PLA trials (P < 0.05); however there were no differences in CHO oxidation. Hunger was significantly lower (P < 0.05) throughout the GAL compared to the GLU and PLA trials. There were no significant differences between trials for energy intake during the postexercise meal. Overall net energy balance for the 24 hours was negative in both the GAL (-162 ± 115 kcal; P < 0.05 vs GLU) and PLA trials (-49 ± 160 kcal).


CONCLUSIONS
Results demonstrate that ingesting a solution containing GAL before and during exercise can positively impact postexercise satiety and energy balance throughout the day, compared to a more readily available and widely consumed form of CHO. Despite this, there appears to be no apparent benefit in consuming a CHO beverage on fuel utilization for this moderate exercise intensity and duration.
a Institute for Sport, Physical Activity and Leisure, Carnegie Faculty, Leeds Beckett University , Headingley Campus, Leeds , UK.
Lauren C
LC
Duckworth
a Institute for Sport, Physical Activity and Leisure, Carnegie Faculty, Leeds Beckett University , Headingley Campus, Leeds , UK.
Susan H
SH
Backhouse
a Institute for Sport, Physical Activity and Leisure, Carnegie Faculty, Leeds Beckett University , Headingley Campus, Leeds , UK.
John P
JP
O'Hara
b Brain, Performance and Nutrition Research Centre, Faculty of Health and Life Sciences, Northumbria University , Newcastle Upon Tyne , UK.
Emma J
EJ
Stevenson
D000293:Adolescent; D000328:Adult; D001628:Beverages; D001786:Blood Glucose / Q000378:metabolism; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D002149:Energy Intake / Q000187:drug effects*; D004734:Energy Metabolism / Q000187:drug effects*; D005260:Female; D005690:Galactose / Q000494:pharmacology*; D006801:Humans; D006815:Hunger / Q000187:drug effects*; D010084:Oxidation-Reduction; D010101:Oxygen Consumption; D010807:Physical Endurance; D005082:Physical Exertion; D012146:Rest / Q000502:physiology; D012420:Running / Q000502:physiology*; D012527:Satiation / Q000187:drug effects; D012528:Satiety Response / Q000187:drug effects*; D013549:Sweetening Agents / Q000494:pharmacology; D055815:Young Adult
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D013549:Sweetening Agents; D005690:Galactose
AUC = area under the curve; CHO = carbohydrate; EE = energy expenditure; FFA = free fatty acid; GAL = galactose; GI = glycemic index; GLU = glucose; PLA = placebo; TEE = total energy expenditure; appetite; energy intake; females; galactose; substrate oxidation