Breaking Up Prolonged Sitting with Light-intensity Walking Attenuated Postprandial Hyperglycemia

Abstract

Sedentary behaviour is a risk factor for comorbidities and mortality regardless of physical
activity level. Experimental data show interrupting prolonged sitting is beneficially associated
with metabolic risk. This study therefore investigated the acute effects of interrupting
prolonged sitting with light-intensity walking on postprandial hyperglycemia in healthy adults.
This study involved thirty normoglycemic participants. Each of the study participants were
given a standard 75-grams glucose. The treatment of the participants was divided into two
trials. First, the control trial, the participants were instructed to sit for five straight hours. The
profile of changes in blood glucose was taken at an inverval of 30 minutes from minutes 0, 30,
90, 120, 180, 240, and 300. Second, the experimental trial where the participants were
instructed to take a short walk for 3 minutes then sit for 27 minutes. Data were analyzed using
paired T-test. There were no significant data difference at the baseline between trials. There
were no significant changes in all the point of blood glucose recordings except at 120 minutes,
where the postprandial blood glucose of the experimental trial with light-intensity walking was
significantly lower than that of control trial. The main finding of this study was that breaking
up sitting time with short bouts of light-intensity activity attenuated postprandial
hyperglycemia. The light-intensity walking attenuated the postprandial hyperglycemia albeit
not significant statistically except at the 120 minutes time point. Postprandial hyperglycemia
is a cardiovascular risk factor in people with Type 2 diabetes and even in nondiabetics.
Reducing postprandial hyperglycemia improves inflammation and endothelial function and
reduces carotid intima-media thickness. Frequent brief interruptions to prolonged sitting with
light-intensity walking, impart beneficial postprandial responses. Further study is
recommended on more prolonged light-intensity bouts of activity and shorter period of sitting.