massive member?

"Even more practical is to avoid constant striving to prolong indefinitely those wonderful times when you're on a roll of PRs. Most of us can peak for about four to eight weeks. At some point you need to recognize that it can't last. It makes sense to regroup and recover for a while before planning new goals. This is the way to avoid overtraining altogether. "

i took this out of massive member's post about weight gain in the articles of interest section. can someone go into to detail about this? what are PR's? and about regroup and recovering does that mean to take a break from lifting?

PR=personal records or personal bests
In otherwords you can't keep going up indefinetly in a straight line,it's more of a jagged curve to the top when you train. Sometimes that means a break from lifting,usually 2 weeks 2x a year for me.