An ectomorph is a naturally skinny person. Gaining weight for you is a real problem. Your metabolism is on overdrive and resists gaining weight. While you may curse your situation most of the world is extremely jealous. You can overcome your natural tendency and gain muscle mass by following the proper ectomorph workout.
One of the blessings and curses of being an ectomorph is your level of energy and activity. You are probably the most bouncy active person you know. We need to put on the brakes on your workout routine in order to start having proper muscle gains.
Your cardiovascular training needs to drop down to a manageable level in order to gain mass. Cut back to 3 workouts per week of only 30 minutes each. This is plenty of time to maintain great cardio fitness without burning away your potential muscle gains.
Your ectomorph workout on weights is going to be much different, too. You cannot afford to spend hours in the gym pumping through a wide range of exercises. You need to hit the mass producing exercises, hit them heavy and hard, and then get out of the gym right away.
Your focus should be on very basic heavy exercises. Use the bench press, squats, dead lift, lat pull downs, barbell curls, triceps extension, military press, leg curl, and seated toe raises. This covers your body parts and allows you to work with heavy weights. Keep your sets and reps low but with heavy weights. Do no more than 4 sets on any body part with reps ranging between 5 to 10 reps per set. Lift heavy!
While you may feel energetic and wanting to keep pumping iron you must stop and get out of the gym. If you keep working out your fast metabolism is going to burn all the calories and nutrients needed to build mass.
The most important part of your ectomorph workout happens outside of they gym. You need to eat more quality calories. Make sure you get a minimum of 1 gram of protein per body part or more. While most bodybuilders are warned to stay away from empty calories, you are free to eat extra calories. Have an extra protein bar packed with calories in the morning, afternoon, and evening. If you feel hungry you must eat.
If you play sports then you must take into consideration your training and adjust your other activities properly. A high school football player who is running sprints, and going through one or two hours of activity a day should avoid all other cardio training. You will need to eat even more to offset this increased activity.
Remember the simplest of facts, your body is highly efficient at burning calories when in motion. Make sure you get plenty of sleep and rest. With lifting heavy, eating plentifully, and getting proper rest your body will begin to gain in size and muscle mass. Your progress will still be slower than other body types, but you do have one big advantage. You never will need to go on a “getting cut” diet. Your body is naturally lean, cut, and with added muscle will be spectacular.