I can speak as a physician, molecular biologist and from personal experience. This is not, however, medical advice. I’m not a specialist in the field; I haven’t examined you; and this is just off the top of my head (the info may be a little out of date)
First off, Human Growth Hormone is probably not even an option at your age. It simply doesn’t do what astro thinks it does.
In low levels it may assist muscle mass development, but risks aside (and I don’t advocate hormones for this kind of use, at all), it’s not the even a particularly good hormone for muscle development at your stage of life. It isn’t particularly efficacious at increasing bone girth.
Since you are 5’ 11", you are most likely at or near your ultimate adult height. Most of your bone growth is over. At doses that affect body form (vs. the low doses used -with debatable safety- to promote muscle growth in older people), you are likely to experience uneven bone growth in the more susceptible joints. Classically this includes acromegaly (uneven growth of some bones of the face and jaw) and arachnodactyly (long spider-like spindly fingers). These were recorded in people with overactive growth hormone long before HGH was available commercially, and are seen in “late stage” juvenile supplementation by physicians. Alas you rarely hear about the “failures” in the rah-rah pro hormone press.
Leaving aside the considerable possible health risks, HGH will primarily act at the remaining active epiphyseal growth plates (thin growth regions near, but not at, the end of your long bones). The result: you’d likely become be taller and ganglier, with possibly some body parts out of proportion (and not the ones you might want). This is called “longitudinal growth” or extension of the long thin bones.
I’m not throwing fancy words at you to impress you. They are useful search terms for you to do your own research, and confirm what I say. I wish there were a simpler way, but the more detailed the concepts, the more you run out of simple words to distinguish between simple ideas. It stuns me that someone can baldly give you advice that might damage you or even eventually shorten your life, without a second thought. There is a reason that some of us spend extra decades in school, hunched over boring books, and it’s not just to make money. I made more money running a computer company in the 1980s than I do now. (But I’m happier now – though I was happy then!)
While bone density (the “bone bank” astro mentioned) is desirable, you are seeking bone girth, which is a very different thing. Both are best helped by exercise, because bone is actively remodeled when a load is placed on it regularly: osteoblast cells constantly lay down new bone throughout your life, and osteoclasts constantly resorb bone to adjust its shape. These processes occur at a significant rate, especially at your age, and when actively stimulated by use: think of your friends who’ve broken bones (a fairly modest injury at 19, but a fairly serious one at 90), and how completely they healed in a matter of months.
I also speak from personal experience. I was skinny at about your age, and grew muscular - a husky he-man, compared to everyone else in my extended family- simply through normal life activities. Since you mentioned watches and wrists, I’ll discuss tha in more detail.
I had slender “surgeon” fingers and hands. (actually, most well-practiced surgeons don’t have those for long–it’s just a popular misconception ) The major power muscles of the hand are in the forearm, and the force is transmitted to your fingers through tendons (put your fingers around your fingers, forearms or wrists and flex your fingers individually: you’ll feel where the muscles doing the real work are) For this reason, normal strength training will mostly build your forearms, not your hands and wrists
The “intrinsic” hand muscles (which will help keep your watch on) are easily and quickly developed by combining force and delicate wor. In my case, I developed both dramatically working on my car (a common teenboy activity, back in my day) doing plumbing (for myself family and friends), home repairs, etc.
This not only strengthened and bulked my fingers/hands, but thickened the bones and tendons of my wrist, By comparison, I’d done a fair amount of martial arts in my late teens (which included some board- and brick- breaking stunts back then), and though that undoubtedly strengthened my bones (and, I often suspect, did a bit of enduring damage) it didn’t bulk up my hands and wrists that much. Trust me, a few hours of straining to awkwardly attach blind nuts, gripping pilers at every angle, hammering studs, fixing plumbing, yardwork etc. each month will make your watches fit, will save you a lot of money, and build valuable sweat equity in your home (or your parent’s home, etc.)
Good results can also come from more “casual” exercises with grip strengtheners, etc. I used those as a teenager, too, but they didn’t have as much effect as the varying challenges of productive work–but in my mid-late 20s and through my 30s, they did have quick, very noticeable effects, and are certainly more convenient later when you have kids, who make more demands on your time
For general body development and basic “bulking up”, I found isometric exercise (straining opposing mucle pairs against each other with no change in body position) to be excellent. I never had a body builder’s physique, but I did put on 20-30 lbs of muscle in several months on a regime of 5-10 minutes of painless exercise 4x a day (often during lectures or while watching TV – it’s an almost unnoticeable activity) There are plenty of good books on stretching and isometrics, and they’ll offer a greater variety of exercises and advice than I can.
Exercise doesn’t have to involve a heath club, equipment or scheduling. Sports and other activities are wonderful for cardiovascular and other benefits, but whether you are athletically inclined or not (I was; it didn’t bulk me up much) you can develop the basic girth and mass you seek with other activities.
I still periodically do those exercises today, and I can see/feel the effects in a matter of weeks. Some of that is from experience (you get better at going the exercises effectively over time) but if I recall correctly, the effects on my upper body development were pretty clear within the first few months when I started as a teenager.
In fact, when I hit send, I’m going to start putting up post-its around the house and office. It’s about time for me to start yet another biennial cycle of isometrics.
