Day 29 and we are using the tabata variation of 50 second work and 15 seconds rest for 4 sets of bridges and 4 sets of superman pose. I like to go back and forth between the superman poses and the bridges for the balance in my back. They use different muscles in the lower back and hips. You only have three more days of this challenge and the worst day is over. So enjoy the last bit and how much stronger you have gotten!