Casein Protein and Leucine Supplementation in Chronic Obstructive Pulmonary Disease (COPD)

The study involves 5 study days. The duration of the first 4 study days is approximately 6.5 hours per day and the duration of the 5th study day is approximately 8 hours. On each of the first 4 study days the effect a casein protein meal with or without leucine and carbohydrates will be examined. On the fifth study day the effect of 4 different levels of casein protein and carbohydrate intake by sip feeding (every 20 minutes) is examined. Also, subjects will receive a mixture of amino acids (little parts of protein) which are a little bit heavier than normal, called stable isotopes. This is the so-called stable isotope method to investigate protein behavior in the body (protein kinetics). Altogether about 75 ml of blood will be drawn per study day to assess outcome measures.