To start, though this has already been established, steroids do the opposite in a sense. Steroids allow the body heal faster, so that one can lift very heavy loads more frequently than they normally could. Whether on steroids or not, if a person just lifts extremely heavy all the time, they will more than likely get hurt eventually. This is because by lifting such heavy weights, they will be making major gains as far as their large muscles are concerned, but their small connective tissue, will not be able to keep up. This unbalanced strength will eventually cause injury (most likely) to those small connective tissue, and that is the reason why one sign of steroid use is break down or constant injury.
Now onto a little biology. Your body has 2 types of muscle fiber, type 1, or slow twitch fibers, these are used for endurance activities, or tasks that don’t require maximum strength; and type 2, or fast twitch fibers, these come into play when a task utilizes more than 25 percent of your maximum strength. The type 1 fibers are what are called “prime movers.” Your body recruits them first in any activity. The the activity takes more strength, than your fast twitched muscles are recruited.
Your small connective tissues are worked every time you do any lift with any load. They however increase in strength at a much slower pace than the major muscles.
So to put it all together, this is one main reason periodization training is so widely accepted. You need to lift heavy to make sure you hit all your fibers, however if you lift heavy all the time you are going to be getting way ahead of your small connective tissue. So by doing periods of heavy weight and low reps, and light weight and high reps, your giving your small connective tissue its best shot at keeping up!
Hope this was able to help and good luck with your training.
