Why do people hit weight lifting plateaus?

[fitwes16]

I always wondered this and i wanted to know if anyone could give me a good answer. Seeing some of the people on here really know there stuff i thought it would be a good question to ask. Why are there weight lifting plateaus when you don't increase as much if at all?

 

[Streamline]

I can give you the simple answer but i'm sure there's a more complicated reason. The simple reason is that your muscles have adapted to the weight training and are no longer as "shocked" as they use to be when you started thus it's harder to get as much growth as you would like to.

 

[NewGenSTi]

added to the theory above when you use the same exercise over and over agian without increasing intensity or reps or anything the targeted muscle grows to a point where the supporting muscles give out before the trageted muscle will. in turn you need to try different variations in exersices to hit supporting mucles so that everything grows together, preventing injust and promoting overall growth.

 

[Hoss]

Streamline hit the nail on the head, adaptation.