Riflewire, we are one.
I am 178-180cm in height and I have gained a considerable amount of mass since I started two years ago, and now at 19 years old I am a minimum 76kg with a BMI of about 23.8.
No one who knew me two years ago believes I should put on any more weight, and I am generally considered solid.
I have shoulders wider than the average and a very well balanced frame - which very evenly develops mass as I gain it, so that I never have a chest larger than the thighs or upper arms larger than the calves.
I would love to gain more weight also, and hope to be about 80kg within the next few months. I would not however wish to be any heavier than 85kg as that would be absurd considering my current and intended employment.
I also recommend listening to Strike if he arrives here, because he gave me very good advice when I first started out. I don't have a knowledge in any way as professional as his, all I will do is share my experience and relate, which sort of advice I have always found helpful from others.
I gain weight rapidly and stagnate for very long periods generally. I live remotely and so have access to nothing other than stones in the field. These are advantageous over the gym weights because if you can handle a 100kg rock and benchpress it - with balanced gym equipment I imagine you could manage much more. My problem is that eventually I find that there aren't any rocks the right size! Nothing that compensates for the next level.
What I want to say is that my circumstance has taught me that weight gain = handling larger weights.
I will struggle and curse heaven and hell rolling a 90kg basket on top of me and then wish I was never born as I try to push him up until my elbows almost lock out. But the next day I will come out and do it twice, and more likely than not if I have kept my body comfortably fed I will be a kilo heavier. And it won't be fat!
So long as I have had the energy and a progressively heavier weight, I have gained sometimes two kilos every week. It is amazing.
But the weight must be heavier. It must be what I see as a 'breakthrough'. What you describe is exercise more suited to toning than weight-gain in my experience. If I can lift the weight for 5 repetitions, I am not gaining anything from it. I lift it once and nearly die doing it. When recovered, I'll lift it twice. Then I will exercise with it until I am just managing to push a rep out of something 3-6kg heavier, and then I'll move on.
This is frustrating for me because I have run out of good rocks completely, and the ones I have found are too heavy or remote to be transported (PARADOX!), so I have attempted circumventing this problem by making breakthroughs wherever I can. I lift the largest weights (~90-105kg) in a benchpress, but anything like a bicep curl or a military press is reduced to something more like ~50 - 65kg. So whereas before I focused on gain through new benchpressing weights, I am now relying solely on attempting to lift larger weights in variations of a bicep curl and this is very hard and very slow.
Finally, I manage to lift with the arms a neat 60kg rock up to the chin, that's a breakthrough. Now tomorrow I will do the same and then push and hold it above my head. That's a breakthrough, now I'll stand with it, bring it up to the chin, up over the head, and then slowly control it as it comes down to the waist level, then back up to the chin. These are all breakthroughs. Now holding it at the chin, push out from the chest and attempt to hold the weight forward of the body. Further each day, another breakthrough.
I find it extremely difficult to make these new levels, much more so than I did when gain was simply a matter of benchpressing a new weight and then delegating it slowly to the arms, since my arms seem to grow but very casually. But once I get to the stage where the breakthrough is 'do this six times instead of five', to my great frustration, I find that nothing more is being gained from it.
My weight is also very dynamic. Whatever I wake up as in the morning I consider to be my base weight (76.4), after a meal, and when I am comfortable it will generally be 77.4, after strenuous, cardiovascular exercise (Or really just work) it will linger between those two. After intense lifting of weights, if I have been successful, the weight will generally rise to 78 - 78.4 in my experience. If I then eat sufficiently and remain well hydrated and rest, maintaining this weight of 78.4, I will likely awaken the next morning at 77-77.4. This will then slowly stabilise as my new base weight, and the process begins again.
I will repeat - this will sound like nonsense to anyone who has studied and knows PT - but this is how it appears to me, an amateur mostly self taught, as I gain the weight.
Anyway, hopefully you will find something in there that may give you new ideas or help clarify something.
The fact that you have gained 5kg in a month shows that you are doing something right, perhaps you could give me some advice, and I assure you I would welcome it.
I would love to know if there is something I can change in all that which will allow me to grow steadily again.
Good luck with it Rhy, and wait for Dr. Strike.
EDIT: I will easily and hungrily consume 3 litres of milk a day, plenty of fish, pasta, some chicken, bread, peanut butter maybe, a burger and chips. But I don't count calories or protein as I am probably not dedicated to this as you are. I simply check my weight and also find it possible to know whether growth is imminent or not by instinct - the body tells when it is in need of something, and a balanced diet (That's right - everything you can lay your hands on!) is my key to covering all possibilities.
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