Watch me push through the pull-up challenge even when I think the song is over! Fitness challenges like this test endurance and determination. Join the fun and see how many pull-ups you can do!

The group was quick to acknowledge the lack of scientific rigour behind the process. This was a self-experiment, not a lab study. As the days progressed, the physical and logistical toll became ...

Watch the video of Dani Arnold speed-climbing the Matterhorn.