Brief Activity Can Help Insulin and Blood Glucose

#front

A study done with kids who were of normal weight found interrupting long periods of sitting with brief moderate-intensity walking periods resulted in improved blood glucose levels.

Keep in mind the walking was “moderate-intensity”, not just strolling about or standing up and moving about a bit.

“Brief interruption of sedentary behavior improves blood glucose in children”  Belcher BR, et al. J Clin Endocrinol Metab. 2015;doi:10.1210/jc.2015-2803.

From an article on the study in Healio Endocrine Today, August 27, 2015, by Amber Cox:  LINK

• Yanovski and colleagues evaluated 28 children aged 7 to 11 years with normal weight to determine whether glucose tolerance could be improved by interrupting sitting with short, moderate-intensity walking bouts.
• In a random order and on different days, participants underwent one of two conditions: continuous sitting for 3 hours (SIT) or sitting interrupted by walking (3 minutes of moderate-intensity walking every 30 minutes; SIT+WALK).
• An oral glucose tolerance test was used to measure insulin, C-peptide, glucose and free fatty acids every 30 minutes for 3 hours.

From the abstract:  LINK

• Interrupting sitting resulted in a 32% lower insulin AUC (P < .001), 17% lower C-peptide AUC (P < .001), and 7% lower glucose AUC (P = .018) vs continuous sitting.
• Conclusions:
  Interrupting sedentary time with brief moderate-intensity walking improved short-term metabolic function in non-overweight children without increasing subsequent energy intake. These findings suggest that interrupting sedentary behavior may be a promising prevention strategy for reducing cardiometabolic risk in children.

It would be easy to make too much of the “without increasing subsequent energy intake” statement, as this refers only to the meal at the end of the study period. The kids were offered a buffet meal after both protocols. The calorie intake at that meal did not differ significantly between the two study conditions. Of course, it would be completely inappropriate to conclude from that whether or not there were any short term or long term effects on calorie intake or energy balance. In addition, a change in habitual activity over time would be expected to be accompanied by adaptations in the appetite and energy management systems of the body. So, that part of the study does not carry much meaning.

The main part of the study, though, is a useful look at the topic of interrupting continuous sedentary behaviour.