As per a recent NY Times article, ” In a ground breaking 2010 study, researchers in Belgium persuaded young healthy men to stuff themselves for six weeks with a diet consisting of 305 more calories and 50 % more fat than men had been eating. Some of the volunteers remained sedentary while gorging. Others began a strenuous midmorning exercise routine after they had breakfast. The third group followed the same workout regimen, but before they had eaten anything.
At the end of six weeks, the sedentary group gained about six pounds each. They also developed insulin resistance, etc. The men who exercised after breakfast had also packed on the pounds, about three each, and developed insulin problems. But the men who had exercised first thing in the morning, before eating anything, had gained almost no weight and retained healthy insulin levels. Their bodies were also burning more fat throughout the day that were the other men…”