Night owls who exercise in the evenings may be less prone to diabetes

By Mark Waghorn via SWNS

Night owls who like to exercise in the evenings are less prone to diabetes, according to new research from Denmark.

Taking regular exercise late in the day improves older people's blood glucose control.

A study of 775 Dutch men and women found those who were physically active in the afternoon or evening were less likely to develop the disease than morning larks.

Lead author Dr. Jeroen van der Velde, of Leiden University in the Netherlands, said: "Moderate to vigorous physical activity (MPVA) was associated with reduction of up to a quarter in insulin resistance compared with an even distribution throughout the day.

"The time when physical activity is performed may be relevant for metabolic health and may be considered during lifestyle advice."

The participants, aged 45 to 65, were divided into three groups - those who worked out mostly in the morning (06:00-12:00), afternoon (12:00-18:00) or evening (18:00-24:00).

The latter two groups saw reduced insulin resistance, by 18 and 25 percent, respectively.

Dr. van der Velde said: "More MVPA was associated with reduced liver fat and insulin resistance.

"Interestingly, we observed the timing of MVPA during the day was associated with insulin resistance.

"MVPA in the afternoon or evening but not in the morning was associated with reduced insulin resistance."

There was no significant difference in insulin resistance between morning activity and activity spread evenly over the day.

The volunteers underwent a physical examination during which blood samples were taken to measure fasting and 'after meal' blood sugar' and insulin levels.

A combined accelerometer and heart rate monitor worn for four consecutive days and nights recorded movement and activity.

Demographic, lifestyle and clinical information were also taken into account via a questionnaire. Liver fat was measured by an MRI scan.

The timing of physical activity is a relatively unexplored field in human biology and the mechanisms underlying potential benefits remain unclear.

Earlier studies have shown that metabolic responses to high-intensity exercise differed based on the time of day the exercise was performed.

In addition, muscular strength as well as the metabolic function of skeletal muscle cells show a peak in the late afternoon.

It suggests being most active during this period may result in a more pronounced metabolic response than activity earlier in the day.

Dr. van der Velde added: "These results suggest the timing of physical activity throughout the day is relevant for the beneficial effects of physical activity on insulin sensitivity.

"Further studies should assess whether timing of physical activity is indeed important
for the occurrence of type 2 diabetes, taking into account the influence of chronotype (night owl or morning lark)."

The current global obesity pandemic is partially the result of a lack of physical activity combined with sedentary behavior during the day.

It increases the risk of developing metabolic diseases including type 2 diabetes.

The study is published in the journal Diabetologia.