Q&A: Taking breaks from sitting improves fasting glucose, glycemic variability

Frequent breaks from sitting for 3 weeks lowered fasting glucose and glycemic variability in adults with obesity, according to findings published in the American Journal of Physiology.

Erik Näslund, MD, PhD, a professor of surgery in the department of clinical sciences at Danderyd Hospital in Sweden, and colleagues measured continuous glucose and activity with fitted monitors in 16 sedentary individuals (10 women) with a median age of 50 years and median BMI index of 32 kg/m².

After measuring baseline levels, the participants were randomly assigned to habitual lifestyle activity or were tasked with taking frequent breaks from sitting. The intervention involved at least 3 minutes of physical activity with low-to-moderate intensity every 30 minutes for 3 weeks.

The researchers observed that individuals tasked with breaks from sitting increased their median daily steps by 744 and daily walking time by 10.5 minutes. The fasting glucose levels (-0.34 mmol/L) and glucose variation (coefficient of variation = -2%) were reduced in those who took breaks from sitting, with greater improvements among those with higher levels of daily activity, according to the researchers.

Overall, longer durations of activity could promote greater health benefits, Näslund and colleagues noted.

Healio Primary Care spoke with Näslund to learn more about the intervention.

Healio Primary Care: What surprised you about the results?

Näslund: I had expected the magnitude of effect to be somewhat greater.

Healio Primary Care: What prompted this research?

Näslund: There are several studies that have examined the effect of breaking sedentary lifestyle in a laboratory setting. These studies have been short (1 day) and under controlled circumstances. They have shown a significant positive impact on metabolic health with improved glucose tolerance. We wanted to test if this also held true in a real-life setting over a longer time period.

Healio Primary Care: What is the clinical relevance of the findings?

Näslund: These results are not limited to persons with obesity. A sedentary lifestyle independent of weight is not good for your cardiometabolic health. However, obesity is a risk factor for poor metabolic health, hence why the results may be of specific importance for persons with obesity. The results show that this modest increase in activity only has a small impact on metabolic health. For a greater effect, it is most likely that an increased intensity in the activity is needed.

Healio Primary Care: Did the timing of the break sitting have an impact on the results?

Näslund: We did not study that, and the number of participants was too small to determine that. What we did see was that in some participants, the adherence to the protocol decreased over time, demonstrating how difficult behavioral changes are.

Healio Primary Care: What are the next steps for this research?

Näslund: The next step is to see if a greater dose/interruption has a greater impact on metabolic health and what type of “exercise” has the best benefit. There are studies that suggest that [high-intensity interval training] has a positive impact, but that might not be feasible for most people to do in their daily life.

A sedentary lifestyle is not good for you. We need to find effective ways in real life to counteract that lifestyle. The most effective way has not been determined. If that is taking the stairs instead of the elevator and getting up several times over the day or getting off a bus stop early and walking home is not clear. I think that each individual needs to find what suits that person best.

Reference:

Smith JAB, et al. Am J Physiol Endocrinol Metab. 2021;doi:10.1152/ajpendo.00599.2020.