Whats the best way to gain weight – preferably lean muscle mass, and not fat?
Strength training exercises (weight training, not cardiovascular exercise) are a great way to increase muscle size and shape (adding weight to your body in the form of muscle rather than fat). Regarding your diet, choose plenty of high-quality, nutrient-dense foods that are also high in protein. Good choices include skinless chicken and turkey, eggs, low-fat dairy products, nuts, unsalted seeds, very lean red meat, pork tenderloin, fish and shellfish. Complex carbohydrates are also nutrient-dense, so choose whole grains, whole wheat bread, pasta, brown rice, legumes, fruits and vegetables (versus white flour products, high-sugar foods and processed meals). Since you may reach satiety early, eat several small meals and snacks throughout the day. Start with a wholesome breakfast (whole grain cereal with milk or a high-protein shake and eggs); grab a handful of nuts with raisins mid-morning; for lunch, choose grilled chicken or shrimp over pasta with whole grain bread; have an apple with