You eat the same amount, and don’t change your fat, protein or carbohydrate intake. But still you burn more fat and build up more muscle tissue. Yes, say researchers at Michigan State University, it’s possible. All you have to do is time your protein intake a little better. Drink your shake before your training session, and watch what happens.
This study is also about EPOC, excess post-exercise oxygen consumption. EPOC stands for the extra energy that a body uses after an intensive training session. The EPOC right after the training session is determined by “elevated body temperature, resynthesis of glycogen from lactate, ion redistribution, replenishment of oxygen stores in blood and muscle, resynthesis of adenosine triphosphate and creatine phosphate, increased circulation and ventilation, and residual hormone effects”, the researchers write. But in the longer term it’s the recovery and manufacture of muscle tissue that increases energy use. Twenty percent of the energy that an athlete expends while resting goes towards making and repairing muscle tissue. And manufacture of muscle tissue means protein intake.
That’s why the researchers wanted to know whether it makes a difference if you consume extra proteins just before training. They already knew that your EPOC is lower if you are on a diet. So the researchers measured the energy expenditure of 8 test subjects [5 men, 3 women] who did regular strength training. The measurements were taken over a period of 4 days. The test subjects trained on day 2.
The researchers measured the subjects’ energy expenditure over two 4-day periods. On one occasion the subjects drank a shake containing 18 g whey 20 minutes before they did a full body training using 9 basic exercises. On the other occasion they drank a shake containing 19 g sugars.
The graph below shows that just one shake raised the energy expenditure on the day after the training. The sugar shake caused an increase of 3.5 percent, and the protein shake caused an increase of 8.5 percent.
The rise in energy expenditure, the Americans discovered, was accompanied by a rise in fat burning. It seems that the simple whey shake before training raises not only the production of muscle tissue, but also fat burning.
The table below shows how much energy, fat, protein and carbohydrates the test subjects ate in total. The protein shake group did not eat more proteins over the course of the day than the carb shake group. The athletes’ protein intake was on the modest side anyway.
“Ingesting protein prior to heavy resistance training may be a simple yet effective strategy in order to increase energy expenditure”, the researchers conclude. “Over time consistent increases in post-exercise resting energy expenditure could facilitate reductions in body fat mass and improve body composition if energy intake is controlled.”
The protein shake the researchers used contained whey. Whey is a fast protein. You see an amino peak in the blood within ninety minutes after consumption. Perhaps you need to consume slower proteins, such as casein, longer than 20 minutes before you start to train if you want to achieve an effect like the ones the Americans report.
Med Sci Sports Exerc. 2009 Apr 4. [Epub ahead of print].