A study in fruit flies by German researchers has provided new insights into how exercise promotes good health.
A team, led by the Julius-Maximilians-University of Würzburg (JMU), studied fruit flies when they were walking and flying to see how the activity of insulin-producing cells were affected by the movements.
Insulin is an essential hormone for many animals, including humans, and its most important function is to regulate blood sugar levels and the supply of energy in the body.
By measuring the activity of these insulin-producing cells in the brain (human insulin is released in the pancreas, but has the same function), the researchers found that exercise stopped the activity of the cells, whereas it rapidly increased when the flies were not moving.
Dr Sander Liessem, at JMU, said: “We hypothesise that the low activity of insulin-producing cells during walking and flight contributes to the provision of sugars to meet the increased energy demand. We suspect that the increased activity after exercise helps to replenish the fly's energy stores, for example in the muscles.”
Reduced insulin is also known to contribute to longevity in humans, mice, flies and other animals.