High Knee Tap

What the high knee tap actually trains

A high knee tap is a running drill performed on the spot, where you drive each knee up towards hip height and tap it with the opposite hand.

The hip flexors lift the knee, the quadriceps and glutes handle the brief stance phase, the calves absorb and return each contact, and the abs stop your torso rocking back. It is a genuinely coordinated movement involving most of your body, which is why it is filed under full body.

What it does not do is train any of those muscles in a meaningful sense. The load is your bodyweight, moving fast, in a very short range, hundreds of times. Nothing is held under tension. Nothing approaches the effort needed to drive growth. Schoenfeld and colleagues found a dose response between weekly hard sets and hypertrophy, and this drill contributes precisely zero hard sets.

Once you accept that, it becomes clear what it is actually for.

It is one of the best general warm ups available. It raises your temperature quickly, rehearses hip flexion and quick ground contacts, and needs no equipment, space or skill. Two rounds of thirty seconds before a lower body session leaves you noticeably readier than a slow treadmill walk.

It is also decent low intensity conditioning if you have nothing else, and available in a hotel room.

The one thing worth being firm about is the knee height. The name of the drill is doing a lot of work. A fast shuffle with the knees barely rising is just jogging on the spot with more noise. Pallares and colleagues found full range training outperformed partial range work in the gym, and the same instinct applies to a drill: if you are going to do it, do the whole movement.

The hand tap exists to enforce that. It gives you a target and it forces the arms into the pattern.

Setting up and executing

Stand tall with your feet under your hips and rise onto the balls of your feet.

Brace the abs lightly and keep the ribs down, so your torso does not tip backwards as the knees come up.

Drive one knee up towards hip height and tap it with the opposite hand.

Return that foot to the floor underneath your hips, not out in front, and drive the other knee up immediately.

Keep the ground contacts quick and quiet. If you can hear yourself thudding, you are landing flat and heavy.

Hold the torso upright throughout, and slow the cadence down before you stop rather than halting abruptly.

The mistakes that cost you the most

Knees never reaching hip height is the fault that empties the exercise. It happens because a low, fast shuffle feels more athletic than a high, slower one, and because nobody is checking. The hand tap is the check. If your hand is not meeting your knee at roughly hip height, either lift the knee properly or drop the cadence until you can.

Leaning back is the way people fake knee height without producing it. Tipping the torso backwards brings the thigh closer to the chest without any extra hip flexion, and it loads the lower back in extension while you bounce. McGill's work on core training emphasises holding the torso stiff and neutral under load, which is exactly what stops this.

Heavy heel contacts beat up the shins and slow everything down. Kassiano and colleagues found calf growth responds to work at long muscle lengths, which is worth knowing mainly because it tells you this drill is not calf training either: the contacts here are short, springy and quick by design.

Arms doing nothing is a small thing that changes the drill more than you would expect. Reaching the hands to meet the knees keeps the rhythm honest.

And treating it as leg training is the mistake that wastes your week. It is a warm up.

Sets, reps and rest by goal

Programme it as time, not reps, and mostly as warm up.

If muscle gain is the goal, two rounds of thirty seconds with thirty seconds between them, before your first lift. That is a warm up dose and there is no reason to do more.

For strength, two rounds of twenty seconds, slightly gentler, purely to raise temperature and rehearse coordination before heavy work.

In a fat loss phase it can be used as conditioning proper: six rounds of thirty to forty five seconds with thirty seconds rest, done briskly, is a reasonable session when you have no equipment.

Refalo and colleagues found lifting sets stopped short of failure produced comparable hypertrophy to sets taken to failure. That is a hypertrophy finding, not a cardio one, but it supports the general point that maximal effort is not the only useful setting, and a warm up should never be near it.

Progress by cadence and knee height rather than duration. Long slow rounds are the version nobody benefits from.

Where it fits in your split

At the front of a session, in the warm up, on any day.

On push, pull and legs it works as general preparation before the first lift, or as a filler between sets when you want to keep moving. On an upper and lower split it belongs in every warm up. On a bro split it is either a warm up or a short conditioning block at the end. On a full body programme it is the fastest way to get your temperature up before the first lift.

If you are using it as conditioning rather than a warm up, put it at the end and keep it brief.

The thing it genuinely earns its place for is preparing the hips. Most people sit all day and then walk into a gym to squat, and a drill that repeatedly takes the hip through active flexion is a better preparation than static stretching.

Daily is fine. There is nothing here to recover from.

Variations worth knowing

Plain high knees, without the hand tap, let you run a faster cadence, at the cost of the height check the tap provides.

High knees with travel, moving forwards rather than staying on the spot, add a real running demand and are the better option outdoors.

Butt kicks reverse the emphasis, bringing the heels to the glutes and loading the hamstrings on the recovery phase instead.

A-skips add a skipping rhythm to the same knee drive and train coordination and timing more deliberately, which makes them the better sprint preparation.

The standing knee to elbow is a slower marching version with a crunch at the top, which is easier and considerably more abdominal.

And mountain climbers take the same knee drive into a plank position, which loads the shoulders and abs far more and takes the impact out entirely.

What the evidence says

The pool here is a resistance training pool, so what follows applies general principles rather than pretending these studies examined running drills.

Schoenfeld and colleagues found a dose response between weekly hard sets and hypertrophy, which is the direct reason to file this drill as a warm up rather than as leg volume.

Refalo and colleagues found sets stopped short of failure produced comparable hypertrophy to sets taken to failure, supporting the idea that useful training does not require maximal effort, and that a warm up should sit well below it.

Pallares and colleagues found full range training beat partial range training for strength and hypertrophy, which is the argument for actually getting the knee to hip height rather than shuffling.

Kassiano and colleagues found greater calf growth after training at long muscle lengths, which explains why quick springy ground contacts do nothing for calf size even though the calves are working hard.

McGill's work on core training emphasises stiffness and a neutral torso, which is exactly what stops the backwards lean that fakes knee height.

Speirs and colleagues compared unilateral and bilateral squat training and found single leg work built strength effectively, a useful contrast with the unloaded single leg contacts happening here.

And Vigotsky and colleagues warned that surface electromyography amplitude does not tell you how much a muscle is being trained, which is worth remembering whenever a simple bodyweight drill is sold as a muscle builder.

Common questions

Is this a workout or a warm up?

A warm up, almost always. It raises temperature, rehearses hip flexion and quick contacts, and asks nothing you need to recover from. It can serve as conditioning if you have no equipment, but it is not competitive with a bike, a rower or a brisk walk uphill.

How high do the knees actually need to go?

Hip height. That is the whole point of the drill and the reason for the hand tap. Below that you are jogging on the spot, which is a fine way to raise your heart rate and a poor way to prepare your hips.

Why do I feel this in my lower back?

Because you are leaning back to make the knees feel higher. Keep the ribs down and the torso stacked over the hips, and lift the knee with the hip flexor rather than tipping the body away from it.

Will it build my legs or my abs?

No. The load is your bodyweight moving quickly through a short range, which is nowhere near enough tension to drive growth in either. Your abs work to hold posture, which is worth something for coordination and nothing for size.

How is it different from mountain climbers?

Same knee drive, different position. Mountain climbers put you in a plank, so your shoulders and abs carry a real load and the impact disappears. High knee taps keep you upright and springy, which makes them the better warm up and the worse conditioning tool.