Whenever I workout, unless it's the first week of a new program or something, my body is never sore the next day. I've always guessed that it's just my muscles adapting to the workout plan I've created. I've always heard that you don't want to let your body adapt to anything because then it slows your progress down. How do I shock my body so that my muscles don't adapt to what I'm doing?

Maybe work out super strenuously?

It shames me to say this but I don't know what that means.

It's called DOMS (delayed onset muscle soreness) and the more you workout usually you're less likely to be sore the next day unless you're going intense in the gym. Don't worry about it

You can always tell a new lifter or one that hasn't been to the gym in a while because they complain about not being to walk down stairs, or move their arms the next day or something. Your body will adapt to lifting more with less soreness but that doesn't mean the workout wasn't effective.

 

I'm all in favour of changing up a routine a bit (vary repetitions, the exercises used for various body parts etc.) to break plateaus but not being really sore the next few days isn't a plateau, I wouldn't worry about it.

Just try harder workouts. sometimes you may not be sore but you will be more sore than usual.

Soreness does not always indicate an effective workout. As long as you're progressing it shouldn't be a problem. If you're looking to obtain that ever so sweet DOMS once more then do exercises that you hate or neglect. Progress in those exercises until you start to plateau out then go back to the exercises you originally did. Changing up rep schemes is also a good way to shock.