by Exercising in the afternoon or evening may be better for blood sugar control than spreading activity throughout the day, research suggests.
A new study published in the journal Diabetologia found that exercising between noon and midnight could reduce insulin resistance by up to a quarter.
Insulin resistance occurs when muscle, fat and liver cells struggle to respond to insulin and cannot easily absorb glucose from the blood.
This results in the pancreas producing more insulin to help glucose enter the cells.
Blood sugar remains in the healthy range as long as the pancreas can produce enough insulin to overcome the weak response of the cells, but sometimes glucose levels rise too high and sugar remains in the bloodstream.
This can lead to pre-diabetes (the stage before diabetes is diagnosed) or diabetes.
The new study was led by Dr Jeroen van der Velde and colleagues from Leiden University Medical Center in the Netherlands.
Previous studies have shown that exercise is linked to improved insulin sensitivity, thus reducing the risk of developing diabetes.
The team used data from the Dutch study Epidemiology of Obesity (NEO), which included men and women aged 45 to 65 with a BMI of 27 or more (putting them back into the overweight or obese category).
A separate group of people was used as a control group, meaning the overall study included 6,671 people.
Participants underwent a physical exam during which blood samples were taken to measure blood glucose and insulin levels during fasting and after eating.
People were also asked about their lifestyle, and some were randomly selected to measure liver fat content using MRI scans.
A random group of 955 people were also given a combined accelerometer and heart rate monitor to wear for four consecutive days and nights to monitor movement and activity levels.
About 775 people with complete data were included in an analysis.
The results showed that spending time on moderate to vigorous physical activity reduced the fat content in the liver and also reduced insulin resistance.
Physical activity in the afternoon or evening was linked to reduced insulin resistance, by 18% and 25%, respectively, compared to a uniform distribution of activity throughout the day.
The study found that there was no significant difference in insulin resistance between morning activity and evenly distributed activity throughout the day.
The researchers concluded: “These results suggest that the timing of physical activity during the day is relevant to the beneficial effects of physical activity on inulin sensitivity.
“Further studies should evaluate whether the timing of physical activity is really important for the onset of type 2 diabetes.”
