You do the same in jumping stilts. You move arms and body in the air to increase jump amplitude, and land on a straight leg to compress the stilt and let it bou

You do the same in jumping stilts. You move arms and body in the air to increase jump amplitude, and land on a straight leg to compress the stilt and let it bounce back. If you try working with hips/knees while touching the ground, you'll amortize all the energy you generated, and exhaust quickly. Beginners suffer from this, and it takes some learning to run properly. Also, the energy converts from motion into spring load and back into motion, and you can keep adding it. Pro stilt jumpers can jump several times with more and more energy and increase height. When I took such classes of spring stilts, the coach showed us jumping above 2.5 m. Me and a classmate held a ribbon in our hands above our heads (we stood in stilts too), and he jumped several times towards us, each time higher, and finally flew above the ribbon. This is actually much more work than olympic jumping, where the COG of the jumper is actually a bit lower than the bar. This guy had to jump with COG much higher than the ribbon. But as I mention in the other post, if you fall down even routinely while running on stilts, it's very painful -- falling forward with your arms extended ahead, you still hit the ground with the ribs. Then they ache a month.