Exercise as an appetizer for breakfast

I read last week in the NYTimes about a recent study in the Journal of Physiology did an interesting experiment involving athletes and timing of exercise compared to when they ate breakfast. During the experiment they fed three groups of athletes a diet with an excess of calories which means that each group was expected to gain weight.

The first group did no exercise for the six weeks of the experiment and ate 30% more calories than would be appropriate for their need. In the end they gained an average of 6+ pounds (big surprise, huh?). Moreover, they saw in just those six weeks a decrease in insulin sensitivity, which is considered main causal problem in Type 2 diabetes.

The second group ate their excess calories in carbohydrate and ate carbs during exercise. Not terribly dissimilar from what a normal athlete would do other than eating excess calories. The results for this group were kind of boring. They gained a little weight because of the excess calories, but the rest of the findings were just kind of blah.

The third group, though, that exercise before breakfast and didn't eat anything during exercise was really interesting. They found that this group not only didn't gain a significant amount of weight, but the group also had increased insulin sensitivity and increased fatty acid oxidation (they used fat better for fuel). Their conclusion was somewhat novel (and a little cocky): "This study for the first time shows that fasted training is more potent than fed training to facilitate adaptations in muscle and to improve whole-body glucose tolerance and insulin sensitivity during hyper-caloric fat-rich diet."

Really it is a pretty cool thing to find out. Lots of athletes know that when they need to drop a little weight, they do a little extra exercise in the morning before breakfast. Bradley Wiggins for instance talked about this being a normal thing for him when he's getting ready to drop a pound or two in preparation for a big race. This study had subjects doing 60-90 minutes of moderate to vigorous exercise which is no small thing. However, the results are also no small thing. If they really hold true, this could be a nice prophylaxis for the holiday season when we are all a little prone to eating more than normal.

One caveat, don't expect your all time greatest results when you exercise before eating or without eating. You can only last so long without fuel and this method essentially has you running on E. If you decide to try it, start easier and work up to your limit instead of just blowing up on your first try.