There are benefits to that pre-breakfast workout

Adapted from Edinburgh RM et al. Journal of Clinical Endocrinology and Metabolism 21 Oct 2019 

Research suggests that blood sugar levels can be better controlled by planned eating and exercise timings.

This study was conducted in Bath and Birmingham and involved a six week trial of 30 overweight or obese men. They were divided into three groups. One group ate breakfast before exercise, one group after exercise and the third group made no changes to their diet or exercise (or lack of it). Groups one and two swapped over after the first six weeks.

The researchers showed that you doubled the amount of fat burned during exercise if breakfast was delayed. This was mainly because the group had lower insulin levels due to their prolonged overnight fast. They could therefore burn more fat in their fat stores or muscle. The groups did not do more exercise than the pre-workout breakfast group.

Groups one and two swapped over after the first three weeks. The men’s BMI averaged at 30 and was closely matched in each group. Although insulin sensitivity was improved in the longer fasting group, there was not any significant weight loss.