Changing the timing of when you eat and exercise can help people better control their blood sugar levels, suggests a new study from the universities of Bath and Birmingham published in the Journal of Clinical Endocrinology and Metabolism.
The six-week study, which involved 30 men classified as obese or overweight and compared results from two intervention groups (who ate breakfast before / after exercise) and a control group (who made no lifestyle changes), found that people who performed exercise before breakfast burned double the amount of fat than the group who exercised after breakfast. They found that increased fat use is mainly due to lower insulin levels during exercise when people have fasted overnight, which means that they can use more of the fat from their fat tissue and the fat within their muscles as a fuel.
Whilst this did not lead to any differences for weight loss over six weeks, it did have profound and positive effects on their health because their bodies were better able to respond to insulin, keeping blood sugar levels under control and potentially lowering the risk of diabetes and heart disease.
- The muscles from the group who exercised before breakfast were more responsive to insulin compared to the group who exercised after breakfast, in spite of identical training sessions and matched food intake.
- The muscles from those who exercised before breakfast also showed greater increases in key proteins, specifically those involved in transporting glucose from the bloodstream to the muscles.
For the insulin response to feeding after the 6-week study, the group who exercised after breakfast were in fact no better than the control group … (Excerpts from University of Bath Press Release, Oct. 18, 2019)