The Founder is my favorite exercise for when I am feeling tight. I have been using is as my go-to drill in order to loosen up for a couple of years now. I wrote about it here with some videos from Foundation Training's Dr. Eric Goodman and Peter Park who also wrote the book Foundation: Redefine Your Core, Conquer Back Pain, and Move with Confidence as well as the Foundation Training DVD. According to their thinking, the core is not just your abs! Think about the core as the muscles around your back, too! Here is a video of Dr. Matt Rabin of the UK using Foundation Training with cycling's Team Garmin. He goes through four of the Foundation Training exercises (there are more) including the Founder, the Windmill, the Lunge Stretch, and the Woodpecker. These are all explained and demonstrated quite well on the other videos, but it is sometimes good to get a fresh look at how to perform an exercise. I highly recommend the Foundation book to understand about strengthening the core as well as trying out these exercises. I never feel sore from doing these exercises and I always feel better after doing them. These drills aren't just specific for cyclists, this video is of a cycling team. They work for anyone, even someone who rides an ElliptiGO!