A double under is when the rope passes under your feet twice on a single jump. It's a staple in CrossFit, a benchmark of jump rope skill, and an incredible conditioning tool. Double unders are harder than they look — but with the right progression, anyone can learn them.
How to do double unders
- 1
Master 50+ unbroken basic bounces first — you need consistent timing.
- 2
Practice 'power jumps' without a rope — jump higher than normal and slap your thighs twice before landing.
- 3
With the rope, do 3 basic bounces followed by 1 double under attempt.
- 4
Jump about 4–6 inches high (higher than a basic bounce) and whip the rope fast with your wrists.
- 5
Keep your core tight and body straight — avoid piking (kicking feet forward).
- 6
Gradually reduce the single bounces between double unders until you can string them together.
Common mistakes
Piking / donkey kicking
Jump straight up. If your feet kick forward, your body is compensating for poor timing.
Using arms to spin faster
Speed comes from your wrists, not your arms. Keep elbows locked at your sides.
Jumping too high
You need only 4–6 inches. Going higher wastes energy and breaks rhythm.
Holding your breath
Breathe out on each jump. Holding your breath causes you to tense up and fatigue quickly.
Pro tips
- ✓Use a speed rope — lightweight cables spin much faster than beaded or PVC ropes.
- ✓Film yourself from the side to check your body position during the jump.
- ✓Once you can do 5 unbroken, you'll get to 20. The hardest part is the first few.
- ✓Practice when fresh — double unders are a skill movement, not a conditioning exercise when you're learning.
More jump rope techniques
Count your double unders reps with AI
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