Laura, I try to encorporate my core workouts with my other workouts. Eg I'll do push-ups with my feet on the ball when I do my strength training and I'll add a little knee tuck on the up part of the push-up and I do pull ups with a rope instead of lat pulldowns, I'll do 8 x 50 butterfly kick with fins when I go to the pool. If I try to make core a separate workout, it never happens. So I sneak it in with the other stuff. I try to work in 5 to 10 min of core 4 to 5 days a week.
Living life like there's no tomorrow.
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2007 Look Dura Ace
2010 Custom Tonic cross with discs, SRAM
2012 Moots YBB 2 x 10 Shimano XTR
2014 Soma B-Side SS