If you can master the technique, skipping is possibly the best drill for developing calf strength for running. It teaches you to use the elastic energy in the calf muscles to keep you in the air, rather than using quad strength to jump up and down. But like anything else in training, your technique is really important.
With good technique, skipping generates eccentric loading in the Achilles and therefore a build up of elastic energy that can be used as a spring to bounce back into the air. I say bounce, because jumping is a huge waist of energy compared to bouncing. Think of it like this: If you took a basket ball, knelt down on the floor and threw the ball up into the air over and over, catching it every time it fell back down, you would use a great deal more effort than if you simply stood up and bounced it off the floor. The ball would travel equally far but its energy gets converted into the bounce, and you only need put in a small force from your finger tips to keep it going because you’re using Potential and Kinetic energy together. The same concept applies to running, the more bounce we can generate, the more force can be applied and the more energy we convert to motion.
So how do we skip effectively? Ideally you need a fast rope like the wire one I’m using in the video. If the rope is too slow you will lose your bounce energy and not get the training adaptations you should be after. It’s like catching the ball and throwing it back into the air. The rope should form a large loop between each hand, which just touches the floor when the hands are held just away from the sides at pelvis height. If the rope is too long it will hit the floor and bounce up, striking your feet. Too short and it will catch your feet on the way through. The right length rope will allow you to bounce 3-5cm up, just enough to miss it. Lastly, spin the rope with your wrists NOT your arms. Spinning with the arms makes the rope track too far back and forth, whilst using only the wrists keeps the rope spinning in the same place. Now for the technique: Let’s begin with the two foot jump. Most importantly you need to keep your body as straight as you can from head to toe so there is no loss of force through weak joint positions. Now simply jump up and down keeping as stiff as you can, only bending slightly at the knees and ankles. The stiffer you can hold the body the more you will generate bounce from your ankles and the faster you can spin the rope.
The next step is to skip from one foot to the other. When doing so, dorsiflex your ankle whenever your foot is off the floor. This generates stretch in the calf, which in turn loads the muscle ready to receive your weight. It is this dorsiflexion which will help train resistance to Achilles Tendinitis by not losing the stored energy. Again the body remains quite stiff with all the bounce coming from the ankles and knees through very small ranges of movement. For an added extra you can throw in some knee raise drills, one foot hopping or anything else you like to make your skipping more fun and creative.
If you are thinking of learning to forefoot run, skipping will give you the resilience needed in the lower leg tissues to avoid overload injuries. Running requires this bounce like action to apply the force you create through your stride into motion. If you don’t bounce you absorb this energy through your muscles and joints causing them to become overloaded. This repetitive overload will then lead to tissue injury. So practice this bouncing technique as much as possible to develop the strength needed to run. If you can’t coordinate the skipping rope to start with then repeat the exercise without it. But it won’t be half as fun to do!