Why can't I jump high?
Ever wondered why you can't jump like your bounciest teammate, or why some people leave the ground like they are on a trampoline? The answer is almost always hiding in one of four places, and most of them you can train.
The four things that decide your vertical jump
Every jump, and most physical performance for that matter, comes down to four things working together:
- Energetics: how your body fuels the effort.
- Biomechanics: your technique, and how you sequence the movement.
- Physics: the forces you have to beat, mostly gravity.
- Physiology: the strength, speed and spring of your muscles and tendons.
Some of these you cannot change much, and some you can change a lot. We will take them one at a time, and for each one look at what is going on and what you can actually do about it.
Energetics: why fitness barely moves your jump
A vertical jump is over in a flash. Even with a run-up you are looking at three to five seconds, and the jump itself is a fraction of that. For a single effort your muscles never get past their stored ATP and a quick dip into phosphocreatine, so your energy systems are not the limit. For one max jump, your tank is not much different to LeBron's or an Olympic high jumper's.
Here is the part most people miss: long, slow cardio can actually rob you of your vertical. It keeps you in a low grade of constant fatigue, and over time it nudges your muscle fibres toward slow, type I endurance dominance, the opposite of the fast, explosive fibres a big jump needs. If hops are the goal, grinding out long steady runs works against you.
The one exception is repeat jumping. If you have to jump again and again across a game, fitness starts to matter. For a single best jump, it does not.
Physics of jumping is all about take-off speed
Jumping is really one job: accelerate your body upward fast enough to beat gravity for a moment. Gravity drags you back at 9.8 metres per second, every second, so the faster you are moving the instant you leave the ground, the longer it takes to turn you around, and the higher you go.
And it is not a straight line. Jump height climbs with the square of your take-off speed. Leave the ground twice as fast and you do not jump twice as high, you jump four times as high. That is why take-off speed is the number that matters, and it is the thread that ties the rest of this article together.
You cannot argue with gravity and you cannot pick new genetics. So the whole game is raising your take-off speed, and that comes from two things you can train: better technique, and a stronger, faster, springier body. The rest of this guide is those two things.
Take-off speed is also the one number worth tracking. The Metric Jump app measures it from your phone camera in seconds, no force plate required, so you always know whether your training is actually buying you height.
How to improve your jump with better technique
Biomechanics is just a fancy word for how you move, your movement skill. After mobility, improving your technical jumping ability is the cheapest free speed boost going. Two parts matter most: how you sequence the jump, and how you use your arms.
Sequence the jump like a whip
A good jump is you coiling your legs tight like a spring, then uncoiling them fast and in the right order. As you drive up, your joints should open from the top down: arms, then hips, then knees, then ankles. Get that order right and you spend more time pushing into the ground while your legs unload faster, which means more speed at take-off.
A bad jumper looks like this.
The lowering phase is slow, and there is a lag at the bottom that leaks energy.
A stronger, springier athlete looks more like this.
They load the lowering phase harder and faster, then turn it around at the bottom in an instant, carrying that stored energy upward instead of losing it. That quick turnaround is the stretch-shortening cycle, and it is the heart of a good jump.
Use your arms (most people leave inches on the floor)
Arm swing is part of sequencing, and it is a bigger deal than people think. A full, aggressive arm swing can be worth as much as 25 percent of your jump height. Your arms load your legs like springs as you drop into the jump, then pull your body upward as you drive out of it, helping your legs push harder into the ground and accelerate faster.
There is a simple test to measure your arm swing contribution. Do one jump with your hands on your hips, then one with a full arm swing, and compare. The gap is your arm swing contribution, and it tells you how clean your sequencing is. Metric Jump runs this test for you: film both jumps on your phone and it measures each one to the centimetre, calculates your arm swing percentage, and tracks it over time — the same comparison testing labs run on force plates, from a device already in your pocket.
For the rest of the movement, our guide on how to improve your jumping technique covers the approach, plant and take-off.
How to increase your vertical jump: strength, power and spring
Technique is what makes sure you are using your full strength, power and mobility to jump higher but once you unlock everything you already have, it’s time to get more. Physiology is how you build more, and it is where the biggest, long term gains live. It splits into three jobs: get stronger, get faster, and get springier. Put simply, Speed x Strength = Power, and power is what launches you.
Get stronger to go higher, relative to your bodyweight
You are throwing your whole body into the air, and bodies are heavy. Fast legs are no good if they cannot produce the force needed to shift your centre of mass off the ground. A few things drive that force, and most are in your control:
- Muscle fibre type. You have a genetic baseline, but you can shift your fibres more than people think. Train fast and explosive and your adaptable hybrid fibres lean that way.
- Calming your Golgi tendon organs. These are the rate limiters in your tendons that hold force back to keep you safe. Strength training teaches them it is OK to let more through.
- Neural drive. A software upgrade for your body. Get your brain and nervous system firing your muscles better and you get more explosive, mostly through training with real intent to move.
- The right amount of muscle. A bigger muscle can make more force, but extra mass also drags you back down. There is a sweet spot. Lighter, leaner athletes often jump higher because they are strong relative to their bodyweight. You can be as strong as a truck, but if you are also as slow as a truck, you will struggle to leave the ground.
If you only chase one quality, chase relative strength, and the easiest place to start at home is calf raises, since your calves are the last thing to leave the ground.
This is exactly the gap our Boring Jump Program was built to close: seven weeks of simple, proven strength and jump work that athletes typically turn into 6–10 cm (2–4 inches) of vertical. No gimmicks, just the fundamentals done in the right order.
Get faster and more explosive
Strength gives you force. Speed decides how fast you can express it, and a jump is over in a blink. It starts with how quickly your muscle fibres can contract, which spins your limbs around your joints faster, and in the right sequence that becomes a faster body and a faster take-off. You build it with plyometrics and plenty of actual jumping, the train-fast-to-be-fast work in the gym and on the court.
Build the spring: mobility and stiff tendons
You can have all the force and speed in the world, but if your joints cannot move through the range to load like springs and then explode into full extension, that force has nowhere to go. The more range you can load through, the tighter you coil and the more recoil you get back. Targeted stretching for the hips, groin, glutes and shoulders is the quickest win for a bigger vertical jump — our five-minute stretching routine is the fastest place to start.
Your tendons want the opposite quality. Where muscles should be supple, tendons should be stiff, so that when your muscles pull on them they barely give and pass the energy straight through, like a strong coiled spring. That stiffness is what makes the stretch-shortening cycle snap, and you build it with strength work, plyometrics and jumping practice. Here is the whole thing in motion.
How to make your jump higher today
You cannot rebuild your physiology overnight, but you can stop leaking the jump you already have. Three things work on day one.
First, warm up to jump, not to sweat. Build up gradually: easy movement, then gentle jumps, then a few hard sub-maximal efforts to wake up your nervous system so your first real attempt is your best. Second, use a full, aggressive arm swing, worth up to a quarter of your height, because most people half-swing or swing slowly and leave inches on the floor. Third, free your hips. Tight hip flexors put a handbrake on your hip extension, and thirty seconds a side gives that range back. Our stretches to jump higher walk through it.
Putting it together
Energetics only limits you when you jump again and again. Physics points the way, take-off speed is everything. Technique, strength, speed, and spring are how you build that take-off velocity, and every one of them is trainable. Work them in that order — our weekly vertical jump workout lays out the exercises for each — and measure your vertical as you go so you know it is moving. Play a jump sport? Our guides to jumping higher for basketball and volleyball put all of this on the court.
Or skip the guesswork entirely. We have spent fifteen years turning this science into sessions, and our vertical jump program hands you the whole thing: seven weeks, every session planned, technique, strength, speed and spring in the right order. Most athletes add 6–10 cm (2–4 inches). It costs less than a single physio visit, and it works.