Immobilisation induces sizeable and sustained reductions in forearm glucose uptake in just 24 h but does not change lipid uptake in healthy men

Key points The trajectory, magnitude and localisation of metabolic perturbations caused by immobilisation (IMM) are unresolved. Forearm glucose uptake (FGU) in response to feeding was determined healthy men before during 72 h forearm IMM, the same measurements were made non-IMM contralateral limb at baseline h. In a similar study design, FGU lipid after high fat mixed-meal (HFMM) IMM limbs. reduced 38%, 57% 46% following 24, 48 respectively, but unchanged limb. A observed HFMM, unchanged. sizeable reduction occurs just 24 which is sustained thereafter specific limb, making unloading per se likely rapid driver dysregulation. Abstract trajectory muscle disuse unknown yet central understanding mechanistic basis immobilisation-associated To address this gap, 10 (age 24.9 ± 0.6 years, weight 71.9 2.6 kg, BMI 22.6 kg/m2) 180 min oral challenge (0) arm immobilisation, non-immobilised (Study A). decreased from (38%, P = 0.04), (57%, 0.01) (46%, 0.06) also 63% less than (P 0.002). second study, nine 22.4 1.3 71.4 2.8 0.8 420 B). responses Study A, pre-immobilisation both arms over study. decrement occurred within that immobilised Increasing availability had no additional impact on rate or these uptake. These findings highlight lack contraction as fast-acting physiological insult FGU.