And would also mean he probably has the best genetics in the world, as most studies show that, naturally, you can't put on more than 1 - 1.5 lbs of lean muscle a month. 2 is top end.
I'm not sure if I would go quite that far, for young men with
insane genetics I wouldn't be surprised if around 5 lbs per month of lean muscle was possible to sustain for a couple months, but these would be the
absolute outliers. I've talked about this before with friends who are personal trainers who have obviously trained a lot of athletes, and they seem to think that sustained gains of about 2 lbs/month of lean muscle (and more like 4 lbs/month of total weight, with this all being truthful to yourself, not lying to yourself by taking the extreme low/high weight days based on fluctuations in water/carb storage, or about how much fat you've put on) is a good upper end goal for an average guy on a heavy bulking program/diet, but one that most guys (even with very hard work, eating tonnes of calories/protein) will not be able to consistently achieve. But RNH wouldn't be just bulking, he's a hockey player, not a body builder, so he's gonna be focusing just as much on speed/quickness/explosiveness, cardio, on ice skills, etc. Plus he seems like an ectomorph too, who would be on the low, not the high end of favourable genetics for gaining muscle.
I think this is a good little writeup:
What constitutes a "challenging but realistic" goal when it comes to building muscle?
You might not like what I'm about to say, but I'm going to say it anyway. The fact is that some people have very favorable "muscle building" genetics and will see impressive results after only a few months of lifting weights. Others will build muscle more slowly. And that's just the way it is.
Yes, I know there are plenty of people running around trying to persuade you that they have "the key", be it a super-secret training program or exotic supplement- to putting on 50 pounds of muscle in [INSERT COMPLETELY UNREALISTIC TIME FRAME HERE].
Truth is, if you're just starting out lifting weights, you're doing extremely well to be gaining about 2 pounds of muscle each month, or 24 pounds over the course of a year.
Even Arnold Schwarzenegger, who combined extremely favorable genetics with an almost super-human work ethic, was very happy to out on 25 pounds in WEIGHT (not just muscle) over the course of a year. Here's what he wrote in his autobiography Arnold: The Education of a Bodybuilder...
"Many people regret having to serve in the Army. But it was not a waste of time for me. When I came out I weighed 225 pounds. I'd gone from 200 to 225. Up to that time, this was the biggest change I'd ever made in a single year."
So if Arnold says that 25 pounds was as much as he'd ever gained in one year (and not all of this was muscle), you'll be doing well just to match it, let alone beat it.
From:
http://www.thefactsaboutfitness.com/building-muscle-fast/
So if 2 lbs per moth was great gains for a young Arnold Schwarzenegger, you have to think that 4 lbs a month of
lean muscle mass for an ectomorph like RNH would be pretty nuts.