This weekend, my brother was flipping through the TV channels, and a very interesting sport came on. The Dutch sport of Fierljeppen, similar to pole vaulting, involves a person sprinting, jumping onto a long pole at an angle, climbing to the top of the pole while it tilts over, and hopefully landing on sand on the other side of a pond. This sport is also known as canal jumping, as the athlete clears a body of water. In terms of the energy of Fierljeppen, here it goes. A person of mass, m1, and velocity, v1, applies a force to an angled pole of mass m2, and an initial velocity of zero. When the athlete grabs onto the pole, the kinetic energy of the athlete is converted to potential and kinetic energy of the system (athlete and pole become a system of mass (m1+m2) until the athlete releases the pole, and lands in the sand). As the person climbs up the pole, the kinetic energy decreases, and potential energy increases to the 90 degree point. It's basically free fall from that point. Hopefully the sand is deep, and the pole doesn't break!
Click on this link to watch this peculiar sport.