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Background: The aim of this randomized, 3-period, 3-treatment crossover trial was to examine the acute effects of regularly breaking up seated office work with short bouts of standing or light-intensity walking on postprandial interstitial glucose concentration. Methods: Seventeen middle-aged office workers performed 3 5-hour trial conditions at their workplace in a random order: 1) uninterrupted sitting, 2) sitting interrupted by 2 minutes of standing every 20 minutes, and 3) sitting interrupted by 2 minutes of light-intensity walking every 20 minutes. Participants consumed 2 standardized test drinks at the start of each trial condition and an iPro2 continuous glucose monitoring system (CGMS) recorded average interstitial glucose concentration every 5 minutes for the duration of the study. Results: The 5-hour interstitial glucose incremental area under the curve (iAUC) was 55.5% lower after sitting interrupted by light-intensity walking compared with after uninterrupted sitting (95% CI, -104.2% to -6.8%). There was also a suggestion of a beneficial effect of regular standing breaks, particularly in overweight men, although they were not as effective as the walking breaks (mean difference [95% CI], -29.6% [-73.9% to 14.7%]). Conclusions: Regularly breaking up prolonged sitting lowers postprandial glycemia in middle-aged adults without metabolic impairment. [ABSTRACT FROM AUTHOR]

ObjectiveDietary advice is fundamental in the prevention and management of type 2 diabetes (T2DM). Advice is improved by individual assessment but existing methods are time-consuming and require expertise. We developed a twenty-five-item questionnaire, the UK Diabetes and Diet Questionnaire (UKDDQ), for quick assessment of an individual’s diet. The present study examined the UKDDQ’s repeatability and relative validity compared with 4 d food diaries.DesignThe UKDDQ was completed twice with a median 3 d gap (interquartile range=1–7 d) between tests. A 4 d food diary was completed after the second UKDDQ. Diaries were analysed and food groups were mapped on to the UKDDQ. Absolute agreement between total scores was examined using intra-class correlation (ICC). Agreement for individual items was tested with Cohen’s weighted kappa (κw).SettingSouth West of England.SubjectsAdults (n 177, 50·3 % women) with, or at high risk for, T2DM; mean age 55·8 (sd 8·6) years, mean BMI 34·4 (sd 7·3) kg/m2; participants were 91 % White British.ResultsThe UKDDQ showed excellent repeatability (ICC=0·90 (0·82, 0·94)). For individual items, κw ranged from 0·43 (‘savoury pastries’) to 0·87 (‘vegetables’). Total scores from the UKDDQ and food diaries compared well (ICC=0·54 (0·27, 0·70)). Agreement for individual items varied and was good for ‘alcohol’ (κw=0·71) and ‘breakfast cereals’ (κw=0·70), with no agreement for ‘vegetables’ (κw=0·08) or ‘savoury pastries’ (κw=0·09).ConclusionsThe UKDDQ is a new British dietary questionnaire with excellent repeatability. Comparisons with food diaries found agreements similar to those for international dietary questionnaires currently in use. It targets foods and habits important in diabetes prevention and management. [ABSTRACT FROM PUBLISHER]

Although the mechanisms underpinning short-term muscle disuse atrophy and associated insulin resistance remain to be elucidated, perturbed lipid metabolism might be involved. Our aim was to determine the impact of acipimox administration [i.e., pharmacologically lowering circulating nonesterified fatty acid (NEFA) availability] on muscle amino acid metabolism and insulin sensitivity during short-term disuse. Eighteen healthy individuals (age: 22 ± 1 years; body mass index: 24.0 ± 0.6 kg·m -2 ) underwent 2 days forearm immobilization with placebo (PLA; n = 9) or acipimox (ACI; 250 mg Olbetam; n = 9) ingestion four times daily. Before and after immobilization, whole body glucose disposal rate (GDR), forearm glucose uptake (FGU; i.e., muscle insulin sensitivity), and amino acid kinetics were measured under fasting and hyperinsulinemic-hyperaminoacidemic-euglycemic clamp conditions using forearm balance and l-[ ring - 2 H 5 ]-phenylalanine infusions. Immobilization did not affect GDR but decreased insulin-stimulated FGU in both groups, more so in ACI (from 53 ± 8 to 12 ± 5 µmol·min -1 ) than PLA (from 52 ± 8 to 38 ± 13 µmol·min -1 ; P < 0.05). In ACI only, and in contrast to our hypothesis, fasting arterialized NEFA concentrations were elevated to 1.3 ± 0.1 mmol·L -1 postimmobilization ( P < 0.05), and fasting forearm NEFA balance increased approximately fourfold ( P = 0.10). Forearm phenylalanine net balance decreased following immobilization ( P < 0.10), driven by an increased rate of appearance [from 32 ± 5 (fasting) and 21 ± 4 (clamp) preimmobilization to 53 ± 8 and 31 ± 4 postimmobilization; P < 0.05] while the rate of disappearance was unaffected by disuse or acipimox. Disuse-induced insulin resistance is accompanied by early signs of negative net muscle amino acid balance, which is driven by accelerated muscle amino acid efflux. Acutely elevated NEFA availability worsened muscle insulin resistance without affecting amino acid kinetics, suggesting increased muscle NEFA uptake may contribute to inactivity-induced insulin resistance but does not cause anabolic resistance. NEW & NOTEWORTHY We demonstrate that 2 days of forearm cast immobilization in healthy young volunteers leads to the rapid development of insulin resistance, which is accompanied by accelerated muscle amino acid efflux in the absence of impaired muscle amino acid uptake. Acutely elevated fasting nonesterified fatty acid (NEFA) availability as a result of acipimox supplementation worsened muscle insulin resistance without affecting amino acid kinetics, suggesting increased muscle NEFA uptake may contribute to inactivity-induced insulin resistance but does not cause anabolic resistance.