While normal skipping or rope jumping is fairly trivial (for some people), the double under is a sick VO2 maximizer and is also crazy difficult. For anyone who doesn’t know what a double under is, it’s when the skipping rope passes around you twice in one skip. I have a demo here, where I performed 105 consecutive double unders and then almost died (which is why I thought the title, “Death by Double Unders” was appropriate).
So if you are one of the many, many people who struggle with the double under, but are interested in perfecting it, I thought I’d share a few tips.
1) It’s all in the wrist. When most people begin double unders, they figure that in order to get the rope around twice, they need to jump higher. This is partly true, but if you’re doing a tuck jump and your knees are bending significantly, you’re doing it wrong. Instead of jumping super high, try to flick the rope around faster with your wrists. This does not mean be spastic with the arms. The motion is primarily a forearm through wrist motion. Try not to do the tuck jump. Jump as you normally would (more or less) when you do singles.
2) Timing is key. Again, you want to avoid jumping too high. The first revolution should occur during the upwards motion of your hop and the second revolution will occur in the downwards motion, a fraction of a second before the rope skims the ground.
3) Use a good rope. Unless you’re really comfortable with double unders, don’t use a non-plastic rope. Classic rope moves slowly and is far more difficult to flick around twice. Use a plastic rope with handles that aren’t physically attached to the rope. The handles will stay static when you’re skipping. Make sure that the rope moves well within the handles. Otherwise you will end up with a twisted rope and double unders will be nearly impossible.
4) Do not tense up too much. Many people do this when performing double unders. Their necks and shoulders completely tense up. It’s difficult to avoid, but try and keep things loose. Otherwise you will throw off your breathing and circulation. Given that double unders require significant aerobic work, you need your Krebs cycle working as efficiently as possible.
Hopefully those few points will help you out towards attaining a perfect double under!