What it trains
High knees means running on the spot with an exaggerated knee lift, and your heart rate rises fast. Your hip flexors lift the knees, while your calves and ankles provide the quick push off the floor. Your quads and glutes absorb each landing. Your arms work in time with your legs, just as when you run. The exercise is used both as cardio in short intervals and as a running drill for a high, quick knee drive. Higher knees and a faster rhythm make it harder, and a marching knee lift without the hop makes it easier.
Common mistakes
- Knees dropping as you tire. It easily turns into ordinary jogging on the spot. Do shorter intervals, or slow the rhythm but keep your knees high.
- Arms crossing in front of your body. Your upper body then twists and you lose the rhythm. Swing your arms straight forwards and backwards with your elbows bent.
- Sinking at the hips. Heavy legs make many people bend forward and sit down slightly. Stand tall and imagine a string pulling you up from the crown of your head.
Variations and alternatives
- Mountain climbers drive your knees towards your chest in a plank, with more work for your trunk and shoulders and no landings.
- Jumping jacks are a gentler start when high knees feel too intense.
- Stair running lets your knee lift meet a real height on every step and gives your legs more to carry.
How to plan your sessions
High knees at full speed cannot be held for long, and that is the point. Work for 15 to 30 seconds and rest for the same time or twice as long, 6 to 10 times. As a drill before a run, do 2 to 3 stretches of 15 to 20 metres, moving slowly forward with high knees. A couple of interval sessions a week is plenty alongside other training, and how often should you train shows how to spread them out.
Add five seconds of work, cut the rest or add a round, but choose only one of them each week. The guide to progressive overload explains why. Pain in your knees or hips, as opposed to tired legs, is your cue to stop and see a doctor or physiotherapist.