Week Workout Review; Crossfit?

So this week after my 5K, I took it a little easier on my treadmill and elliptical mileage...
 

I also have been working on toning for 20-30 minutes prior to my cardio work-

• Monday  - Arms
• Tuesday - Legs (Quads/Hammies)
• Wednesday - Core
• Thursday - Shoulders
• Friday - Tri's - Biceps
• Saturday - Extra Core day (sampling for you!)

....and then of course daily  Plankaday; I am working hard towards 1 minute planks.
(consistently, mind you)

 



Last but not least question of the day -

One of my friends is now taking Crossfit classes, she is 'hook', personally it sounds NUTs! (but intriguing as well, could I actually do something like that, push myself to such extremes? Would my body handled it or put me out of normal work out routine for weeks?)  

Have any of you done a Crossfit class? Whats your take if so....