Day 13: 100 Butterfly Sit Ups! | #100AbChallenge w/ Matt Santoro
#100AbChallenge printable: https://www.blogilates.com/100abchallenge-begins-jan-1st-you-in/

How is it already Day 13 of the 100 Ab Challenge?! It's FLYINGGG by! I am going HARD on you guys...