How do you gain 1 to 2 pounds of muscle in 1 week?

Naturally that is very hard... HGH is your best bet but that's not legal other than that eat a lot of protein and spend ours in the gym but do not overdo it and hurt yourself.

Supposedly 80% of your muscle mass is in your legs and back, regardless of the actual number the point is these are the two groups to focus on. The type of workout that builds mass is a hypertrophy workout and the best way to do this is 3 groups of 3-5 sets of 6 reps. 2-3 minutes between groups, 40 seconds to a minute between sets. Try to keep the same weight for all three sets, this means the weight will be relatively far below your max. The last set of the third group should feel insanely difficult but should doable and done to failure. For your back you should do deadlifts, for your legs you should do squats. A workout of this intensity should only be once a week so you will be doing this only twice in your two weight gaining weeks. More important is to sleep at least 7 but ideally 8-10 hours everynight and have 1 gram of protein per pound you weigh and 4 grams of carbs for every pound you weigh daily spread across 5-6 meals (eat meals 2-3 hours apart). Also stay hydrated, have plenty of healthy fats, and try to include vitamins. After recovering for 2-3 days do a similar workout focusing on pecs and shoulders. So:

1. Focus on legs and back

2.Lift weights that are 60%-80% of your maximum. Do 3-5 sets of 6 reps. Wait 30-60seconds between sets. Do 3-5 sets two more times with 2 minutes rest between each group.

3.Eat 1g of protein per lbs you weigh daily. Eat 4g of carbs per pound you weigh daily. Stay hydrated and be sure to intake plenty of vitamins and fats. Spread these across 5-6 meals that are 2-3 hours apart.

4.Try to sleep a minimum of 7 hours a night, ideally in between 8 and 10.

5. Give your body a full week to recover these groups.

6.After 2 or 3 days do the same group/sets/reps system for pecs and shoulders.

7. Be sure to warm up, stretch, and cool down everytime you excercise, focusing on the groups you will be working out. Also during the week you are recovering stretch the muscle groups you worked and do lighter level workouts. A game of soccer, swimming, or a set or two of pull ups and push ups are all good.

7.Listen to your body: don't eat until you feel sick, if the weight you are using is too great lower it, if you feel your body can handle it do 3 groups of an additional excercise for the same muscle group (i.e. do lunges in addition to squats). If you do an additional excercise you will probably only want to do 3 sets per group not 5. Additionally consider alternating excercises in sets (1 set lunges, 1 set squats etc) within each group.

8.Keep in mind this is hugely genetic and also extremely mental. Your back and legs have the most weight but are the least visible parts of your body, you could gain 15 lbs and it might be barely noticeable to the eye. Also intense excercises cause muscles to swell making it seem like your body has gained more than it has. Additionally, 3 lbs of weight gain will not correspond to the same size gains in two different people.

9. I've never used growth hormone and don't know too much about it and don't have a real opinion on it. What I do know is that it doesn't make you bigger but drastically reduces the recovery time needed between workouts. Theoretically taken in small doses for short durations of time it is very safe. I have no idea what the law is concerning it and it is definitely looked down upon by most of society, but what isn't?