Even after upping my weights today, I found Shoulders & Arms to be a lot less challenging than it used to be. Or maybe I'm just tired of it.
One of P90X's strong points is that there's enough variety in the wokouts to keep most of the routines fresh over a 90-day period. (Sadly, the shelf life of Tony's jokes is much, much shorter.) But I've been regularly doing P90X workouts for close to six months now, and while adding Insanity into the mix has helped stave off the tedium a bit, I'm definitely in autopilot mode now with P90X. I'm looking forward to the end of Round 2 not because I'm too exhausted to keep going, but because I can't wait to do something different.
