I would think most of you would remember at a time in your life where you were weak, frail or overweight and could barely lift a bar or do a push-up. I've been there too and like many of you, hated the way I was. When you realized you had enough of being picked on, laughed at and wanted to stop others from calling you names you made a choice to get better, get stronger, grow muscles and be a powerful beast.
If you saw the movie, you noticed that Steve Rogers had a series of serum shots to help shoot up his muscles and make him stronger and taller. This really is a romantic version of what steroids can be and for all intents and purposes its a myth. In reality steroids can make you stronger and bigger but there's a price to pay and have to keep a surveillance on what you do otherwise if you cycle wrong well to be blunt you're s*it out of luck. Rogers' only side effects really of his powers is that he has 4x the capacity of the average man's metabolism and can't get drunk. Side effects of using real steroids can result in increased estrogen, acne, enlargement of chest that can look like a woman's breast and low testosterone if not used properly. That's just the basic things that can go wrong.
The real ways to increase strength and metabolism is to work multiple muscle groups from as many angles as possible whether its working out like a wild animal, lifting odd objects, basic weight lifting, using clubs, maces and hammers its apparent to train the muscles the best way possible without ever needing the use of steroids or P.E.Ds (Those playing the home game that stands for performance enhancing drugs). Real strength however is from using your mind and developing the mind/muscle connection. Practicing this is tougher then just doing exercise but its well worth the training because you can go even further in your training.
If you want fast results that are quicker then a hiccup then take the shortcuts but if you want real results in a fast amount of time then you have to think like a wo/man of strength and power. Example if you practice a Animal Exercise, you have to think like that animal, move the way it does, picture yourself in their environment, when you can do that the better you can make that exercise. In this factor of Captain America, picture as if you were him or picture him being there next to you and helping keep going. Having this type of mindset goes a long way then just going through the motions. You develop will power, perseverance and the thought of not being just an ordinary person, you are strong, powerful and mighty and you will do the best you can.
Like the Captain himself, he puts through others before he puts through himself and is a compassionate hero and makes himself a man amongst men. A bully however takes what strength he has for granted to tortures the weaker person for personal gain and doesn't know the concept of the consequences. A lot of trainees are like that, not all but quite a few and tell people that they should just give up and not go beyond what they're capable of and never encourage them to get better. Don't ever be one of those people cause you at one point were weak and helpless so instead of being an ass, show them a few things as encouragement not for correcting them and giving them crap about it.
Never underestimate the true powers that are inside you. You have the ability to create powerful and ferocious strength and speed and all it takes is a little imagination and a few simple techniques that can help the rest of your life and not just fitness. The Captain uses what he has to defend himself and others and thats one of your important keys to remember, the real thing is train for knowledge and defense, never for attacking or using for personal gain.