Post-Workout Eating Affects Post-Workout Benefits
When it comes to the metabolic benefits of exercise, experts say overall fitness isn't as important as your last workout. That's because many of the metabolic improvements sparked by exercise taper off after a few hours or days. In other words, you can't coast all week on that hard sprint you did a few days ago. As far as your body is concerned, you need to get out there and do it again to keep the fires burning efficiently. But not only does your latest bout of exercise count. What you ate after your most recent workout also matters.
That's because exercise affects your metabolism, making your cells more sensitive to insulin. Insulin is the hormone released in response to rising blood sugar after you eat. It helps shepherd sugar molecules out of the bloodstream and into the cells, where the sugar is burned for energy (and is no longer available to be converted to body fat). Among people who are developing type 2 diabetes, cells become gradually less sensitive to insulin's effects. Eventually, the body produces ever-increasing amounts of insulin in an effort to compensate. Eventually, the part of the pancreas that produces insulin "burns out" and no longer produces any insulin at all. At that point a diabetic person needs synthetic insulin to survive.
According to research reported recently by the American Physiological Society, eating a relatively low-carbohydrate meal after exercising significantly improves the response of the body cell's to insulin, compared to a meal that's more balanced among fats, protein, and carbs. Surprisingly, the calorie content of post-workout meals didn't seem to matter much. Eating fewer calories than a person just burned didn't improve metabolism compared to replacing the calories burned. What really enhanced muscle cells' uptake of sugars for fuel had far more to do with the source of those calories. High-protein meals had the most favorable effects on metabolism.
This, along with similar previous findings, suggests that you can maximize the effectiveness of your workouts by cutting back on carbs after exercise.