Decreased insulin-stimulated brown adipose tissue glucose uptake after short-term exercise training in healthy middle-aged men.
To test the hypothesis that high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) improve brown adipose tissue (BAT) insulin sensitivity.



Healthy middle-aged men (n = 18, age 47 years [95% confidence interval {CI} 49, 43], body mass index 25.3 kg/m2[95% CI 24.1-26.3], peak oxygen uptake (VO2peak) 34.8 mL/kg/min [95% CI 32.1, 37.4] ) were recruited and randomized into six HIIT or MICT sessions within 2 weeks. Insulin-stimulated glucose uptake was measured using 2-[18F]flouro-2-deoxy-D-glucose positron-emission tomography in BAT, skeletal muscle, and abdominal and femoral subcutaneous and visceral white adipose tissue (WAT) depots before and after the training interventions.



Training improved VO2peak(P = .0005), insulin-stimulated glucose uptake into the quadriceps femoris muscle (P = .0009) and femoral subcutaneous WAT (P = .02) but not into BAT, with no difference between the training modes. Using pre-intervention BAT glucose uptake, we next stratified subjects into high BAT (>2.9 µmol/100 g/min; n = 6) or low BAT (<2.9 µmol/100 g/min; n = 12) groups. Interestingly, training decreased insulin-stimulated BAT glucose uptake in the high BAT group (4.0 [2.8, 5.5] vs 2.5 [1.7, 3.6]; training*BAT, P = .02), whereas there was no effect of training in the low BAT group (1.5 [1.2, 1.9] vs 1.6 [1.2, 2.0] µmol/100 g/min). Participants in the high BAT group had lower levels of inflammatory markers compared with those in the low BAT group.



Participants with functionally active BAT have an improved metabolic profile compared with those with low BAT activity. Short-term exercise training decreased insulin-stimulated BAT glucose uptake in participants with active BAT, suggesting that training does not work as a potent stimulus for BAT activation.
Turku PET Centre, University of Turku, Turku, Finland.
Piryanka
0000-0002-2876-1851
P
Motiani
Turku PET Centre, University of Turku, Turku, Finland.
Kirsi A
KA
Virtanen
Turku PET Centre, University of Turku, Turku, Finland.
Kumail K
KK
Motiani
Turku PET Centre, University of Turku, Turku, Finland.
Joonas J
JJ
Eskelinen
Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts.|Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Boston, Massachusetts.
Roeland J
RJ
Middelbeek
Section on Integrative Physiology and Metabolism, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts.
Laurie J
LJ
Goodyear
Turku PET Centre, University of Turku, Turku, Finland.
Anna M
AM
Savolainen
Turku PET Centre, University of Turku, Turku, Finland.|Department of Clinical Physiology and Nuclear Medicine, Turku University Hospital, Turku, Finland.
Jukka
J
Kemppainen
Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway.
Jørgen
J
Jensen
Turku PET Centre, University of Turku, Turku, Finland.
Mueez U
MU
Din
Turku PET Centre, University of Turku, Turku, Finland.|Department of Medical Physics, Turku University Hospital, Turku, Finland.
Virva
V
Saunavaara
Turku PET Centre, University of Turku, Turku, Finland.|Department of Radiology, Turku University Hospital, Turku, Finland.
Riitta
R
Parkkola
Department of Biostatistics, University of Turku, Turku, Finland.
Eliisa
E
Löyttyniemi
Turku PET Centre, Åbo Akademi University, Turku, Finland.
Juhani
J
Knuuti
Turku PET Centre, University of Turku, Turku, Finland.|Department of Endocrinology, Turku University Hospital, Turku, Finland.
Pirjo
P
Nuutila
Turku PET Centre, University of Turku, Turku, Finland.
Kari K
KK
Kalliokoski
Turku PET Centre, University of Turku, Turku, Finland.
Jarna C
JC
Hannukainen
D002001:Adipose Tissue, Brown / Q000187:drug effects* / Q000378:metabolism*; D000328:Adult; D015444:Exercise / Q000502:physiology*; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D005947:Glucose / Q000493:pharmacokinetics*; D006262:Health; D006801:Humans; D007328:Insulin / Q000494:pharmacology*; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology
D005230:Fatty Acids, Nonesterified; D007328:Insulin; D005947:Glucose
brown adipose tissue; exercise training; free fatty acid uptake; glucose uptake; positron emission tomography