Up until this point, no one ever really knew how much assistance the various bands provided when used during a pull-up. This made calculating work performed and avg. power output for band-assisted pull-ups impossible.
By the way, which is harder: using blue and purple (or plain) bands together, or just using the green alone? And just how much harder is the blue band than the green band? What about blue and red? We get these questions all the time at our gym.
During the process of incorporating power calculations into beyond the whiteboard, we decided to measure and quantify the assistance provided by the various colored bands. We now know very accurately how much work is being performed by the athlete during assisted pull-ups. These numbers depend on the weight of the athlete, the distance they travel during a pull-up, and the band(s) they are using for the pull-up. This was a huge step toward our goal of enabling comparison between Rx’d and scaled workouts based on work/power output.
Based on our findings, we have created a PDF that shows the relative assistance of the various bands and band combinations, and have made it available as a free download. We hope that CrossFit Affiliates and individual CrossFitters alike will find it a useful addition to their gyms. Feel free to print it out and post it near your pull-up bars, that’s what we did!
Color Version PDF
Black and White Version PDF
-Jonathan Kinnick and Corey Tripp, originally posted on blog.beyondthewhiteboard.com on 6.20.09