Any field of study is based upon the traditions of its founders. The world of the gun is no different. And the generation of men who founded the art of American Gunfighting, did not hold physical fitness in high esteem. It is not to castigate them, but simply to point out that we are a product of our parents and they of their grandparents. Nobody gives birth to themselves. All that said, we certainly do not live in the world of our parents and grandparents. And we are also not limited to the information of their day. We have far more data than they did, and thus after the head start we received, we can now drive the art forward into the future.
And that is true as we are making far better technical shooters today than was possible in the 1930s, or 1960s. And while men like Jordan and Bryce may have had much more experience at killing, I doubt they were better shots than the students we produce today. As well, I suspect, if Fairbairn and Applegate, and Askins and Bryce, were around today they would be carrying Glocks with red dots. But that is not the discussion today, as can be surmised from the title.
Today we know far more about physical performance, and I think if those men were around today they may well be powerlifting, doing crossfit, or any other of fitness modalities which were so unpopular in their eras. Why is that? Quite simple.
The stronger you are, the harder you are to kill. And conversely, the stronger you are, the easier it is for you to kill those who want you dead.
I like to lead from the front and thus if I make a statement like I did above, I want to show that I live the story I tell. At 57 years old I spend a good amount of time lifting. These very same lifts. I know...the quality of the video is not great, but I shoot these during my workouts to check technique and any small issues that may creep up in the training that I might not notice when I am pulling 400 plus from the deck.
There is a genetic limit I think. It can be surpassed chemically, and I see absolutely nothing wrong with that. I never took part in that simply because in my youth I had no cash and the technology of steroids was not as developed as it is today. No past the 55 mark, partaking in such has other implications according to my research so I have not done anything with them even though I have had ample opportunity. Most of the SpecOps community and virtually all pro athletes use them regardless of what the official position may be.
Now to size. You will only be so big. Stand next to "The Mountain" from Game of Thrones, or a guy like Brock Lesnar and you will see what I mean. No matter how big you are, there is always someone bigger. So what to do?
Understand that you have a natural potential...even chemically enhanced. Not using this as an excuse, but simply as a realistic POV. The "functional fitness" guys and the fat kettlebell swingers who drink a beer between sets nothwithstanding ("I AM STRONGGGGGLIKE BEAR), it is better to be obviously muscular than to be fat and frail looking. It is also better to be strong and muscular, than to be fat and strong. Is there an ego component to it? Sure, but the fat frail and fat strong guys still have an ego...they just have given up on being anything but what they are. The goal then is to be MUSCULAR AND STRONG so when you are wearing a T-shirt, you can still conceal a Glock 19 under it and everyone that sees you immediately thinks "Strong guy".
And if you are at a beach or a pool, maybe nobody mistakes you for Mr, Olympia but nobody is going to say, "hey look at that fat guy" either.
Way to get strong and muscular -
1). Lift weights. I have done the 5x5, 10-8-6-15. 10x3, 8x8, and 4x8-10. All work and you will want to switch from them from time to time.
2). Don't get fat while getting strong. Every so often add one week of nothing but conditioning.
3). Protein is king. During hard lifting I have taken in over 200 grams per day. Its a chore but necessary
4). Don't fear carbs but stay away from sugar and alcohol and for many, wheat, while building.
And compared to many of my staff and students, I am ridiculously weak. You want to be a complete fighter...to be difficult to kill and to know it is easy to grab another man and throw him off a rooftop? Spend more time doing this and less time sitting on your ass.
Here is a great discussion from warriortalk on Fitness and Strength and Training For Size.