Purpose:
To determine whether interrupting sitting with brief bouts of simple resistance
activities (SRAs) at different frequencies improves postprandial glucose,
insulin and triglycerides in adults with medication-controlled type 2 diabetes
(T2D).
Methods:
Participants [n=23, 10 females, Age: 62±8 y (mean±SD), BMI: 32.7 ±
3.5 kg.m-2] completed a three-armed randomized crossover
trial (6-14 day washout): sitting uninterrupted for 7 h (SIT); sitting with
3-minute SRAs (half-squats, calf
raises, gluteal contractions, and knee raises) every 30 minutes (SRA3); and, sitting with 6-minute SRAs every 60
minutes (SRA6). Net incremental areas under the curve (iAUCnet) for
glucose, insulin, and triglycerides were compared between conditions.
Results: Glucose and insulin 7 h iAUCnet were attenuated
significantly during SRA6 (glucose 17.0 mmol.h.L-1,
95% CI 12.5, 21.4; insulin 1229 pmol.h.L-1,
95% CI 982, 1538) when compared to SIT (glucose 21.4 mmol.h.L-1,
95% CI 16.9, 25.8; insulin 1411 pmol.h.L-1,
95% CI 1128, 1767; P < 0.05), and compared
to SRA3 ( for glucose only; 22.1 mmol.h.L-1,
95% CI 17.7, 26.6; P = 0.01) No significant differences in glucose or
insulin iAUCnet were observed comparing SRA3 and SIT. There was no
statistically significant effect of condition on triglyceride iAUCnet.
Conclusion:
In adults with medication-controlled T2D, interrupting prolonged sitting with 6-minute
SRAs every 60 minutes reduced postprandial glucose and insulin responses. Other
frequencies of interruptions and potential longer-term benefits require examination
to clarify clinical relevance.
Funding
This research was supported by a Heart Foundation Vanguard Grant (Award no. 101449), a NHMRC Centre of Research Excellence grant #1057608, and the Victorian Government OIS scheme. A.R.H. and F.C.T are supported by Research Training Program (RTP) Awards. P.C.D., D.J.G., N.O., B.A.K., and D.W.D. are supported by the NHMRC Fellowships scheme.