Effect of carbohydrate ingestion on adipose tissue lipolysis during long-lasting exercise in trained men.
To study whether sucrose administration acts on lipid mobilization during prolonged exercise, we used subcutaneous abdominal adipose tissue microdialysis in eight well-trained subjects submitted at random to two 100-min exercises (50% maximal aerobic power) on separate days. After 50 min of exercise, the subjects ingested either a sucrose solution (0.75 g/kg body wt) or water. By using a microdialysis probe, dialysate was obtained every 10 min from the subjects at rest, during exercise, and during a 30-min recovery period. During exercise without sucrose, plasma and dialysate glycerol increased significantly. With sucrose, the response was significantly lower for dialysate glycerol (P < 0.05). Plasma free fatty acid level was lower after sucrose than after water ingestion (P < 0.05). With water ingestion, plasma catecholamines increased significantly, whereas insulin fell (P < 0.05). With sucrose ingestion, the epinephrine response was blunted, whereas the insulin level was significantly increased. In conclusion, the use of adipose tissue microdialysis directly supports a lower lipid mobilization during exercise when sucrose is supplied, which confirms that the availability of carbohydrate influences lipid mobilization.
De Glisezinski
I
I
Laboratoire des Adaptations de l'Organisme à l'Exercice Musculaire, Service d'Exploration de la Fonction Respiratoire et de Médecine du Sport, Centre Hospitalier Universitaire Purpan, Toulouse Cedex, France.
Harant
I
I
Crampes
F
F
Trudeau
F
F
Felez
A
A
Cottet-Emard
J M
JM
Garrigues
M
M
Riviere
D
D
D000273:Adipose Tissue / Q000378:metabolism*; D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D002241:Carbohydrates / Q000494:pharmacology*; D002395:Catecholamines / Q000097:blood; D005227:Fatty Acids / Q000097:blood; D005990:Glycerol / Q000097:blood; D006801:Humans; D007328:Insulin / Q000097:blood; D019344:Lactic Acid / Q000097:blood; D008053:Lipid Mobilization / Q000502:physiology; D008066:Lipolysis / Q000502:physiology*; D008297:Male; D017551:Microdialysis / Q000379:methods; D008875:Middle Aged; D005082:Physical Exertion / Q000502:physiology*; D013395:Sucrose / Q000494:pharmacology
D001786:Blood Glucose; D002241:Carbohydrates; D002395:Catecholamines; D005227:Fatty Acids; D007328:Insulin; D019344:Lactic Acid; D013395:Sucrose; D005990:Glycerol