High-intensity exercise and carbohydrate-reduced energy-restricted diet in obese individuals.
Continuous high glycemic load and inactivity challenge glucose homeostasis and fat oxidation. Hyperglycemia and high intramuscular glucose levels mediate insulin resistance, a precursor state of type 2 diabetes. The aim was to investigate whether a carbohydrate (CHO)-reduced diet combined with high-intensity interval training (HIIT) enhances the beneficial effects of the diet alone on insulin sensitivity and fat oxidation in obese individuals. Nineteen obese subjects underwent 14 days of CHO-reduced and energy-restricted diet. Ten of them combined the diet with HIIT (4 min bouts at 90% VO(2peak) up to 10 times, 3 times a week). Oral glucose insulin sensitivity (OGIS) increased significantly in both groups; [diet-exercise (DE) group: pre 377 ± 70, post 396 ± 68 mL min(-1) m(-2); diet (D) group: pre 365 ± 91, post 404 ± 87 mL min(-1) m(-2); P < 0.001]. Fasting respiratory exchange ratio (RER) decreased significantly in both groups (DE group: pre 0.91 ± 0.06, post 0.88 ± 0.06; D group: pre 0.92 ± 0.07, post 0.86 ± 0.07; P = 0.002). VO(2peak) increased significantly in the DE group (pre 27 ± 5, post 32 ± 6 mL kg(-1) min(-1); P < 0.001), but not in the D group (pre 26 ± 9, post 26 ± 8 mL kg(-1) min(-1)). Lean mass and resistin were preserved only in the DE group (P < 0.05). Fourteen days of CHO-reduced diet improved OGIS and fat oxidation (RER) in obese subjects. The energy-balanced HIIT did not further enhance these parameters, but increased aerobic capacity (VO(2peak)) and preserved lean mass and resistin.
Sartor
Francesco
F
School of Sport, Health and Exercise Sciences, Bangor University, George Building, Holyhead Road, Bangor, Gwynedd, UK.
de Morree
Helma M
HM
Matschke
Verena
V
Marcora
Samuele M
SM
Milousis
Athanasios
A
Thom
Jeanette M
JM
Kubis
Hans-Peter
HP
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism / Q000502:physiology; D031204:Caloric Restriction; D050528:Diet, Carbohydrate-Restricted; D015444:Exercise / Q000502:physiology*; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood / Q000378:metabolism / Q000502:physiology; D007333:Insulin Resistance / Q000502:physiology; D016753:Interleukin-10 / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D020738:Leptin / Q000097:blood / Q000378:metabolism / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000378:metabolism* / Q000503:physiopathology*; D010101:Oxygen Consumption / Q000502:physiology; D052243:Resistin / Q000097:blood / Q000378:metabolism / Q000502:physiology; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
D001786:Blood Glucose; D007328:Insulin; D015850:Interleukin-6; D020738:Leptin; D052243:Resistin; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10