The straight foot lock: how it works and how to do it

Technique guideUpdated 25 Oct 2026

Our AI analyses your rolls. Free to try.

Try a free analysis

Download on theApp StoreGet it onGoogle Play

By Scott Flear, founder of JitsAI.

What is a straight foot lock?

The straight foot lock goes by a lot of names: straight ankle lock, Achilles lock, or just footlock. It’s a leg lock in Brazilian jiu-jitsu and the one most beginners learn first.

In IBJJF competition it’s on the illegal-moves table only for the 4 to 12 and 13 to 15 age groups, so adult white belts can use it. Turning towards the foot that isn’t under attack while you finish is illegal below brown belt (IBJJF Rule Book v6, 2024).

How does a straight foot lock work?

A pivot and a lever. Your wrist presses into the back of the ankle and their foot is bent down over it.

• Your wrist is the pivot. The thumb-side edge of your wrist sits on the Achilles, just above the heel. A pull from behind forces the ankle joint into maximum pointing (Hasegawa et al. 2026).
• The front of the ankle stretches. The tendons that lift the foot and toes, the front of the joint capsule and the ligaments on each side are put under tension (Hasegawa et al. 2026). In donor ankles, the front bands of the inner ankle ligament started to tighten at 10 to 15 degrees of pointing and kept tightening (Takao et al. 2020).
• The Achilles gets squashed, not torn. The Achilles is the pivot, so it’s compressed. The risk there is bruising, not a rupture (Hasegawa et al. 2026). That compression is a big part of why it hurts.

If the foot turns inwards as you finish, the little ligament on the outside of the ankle, the one people roll, comes into play too. That’s the ATFL, and it’s the injury recorded from a footlock in competition (Scoggin et al. 2014).

Episode 1 of our Anatomy Series is the physics of levers: the further from the pivot you push, the more twist you get. In the straight foot lock, your wrist is the pivot and their foot is the lever.

How do you do a straight foot lock?

These steps start in a basic leg entanglement (ashi garami), as coaches like Johnny Tama teach it. Steps 3 and 6 are the ones that make it work.

1. Step 1: Foot on the hip, leg between theirs. Put your outside foot on their near hip and thread your inside leg between their legs, controlling the knee.
2. Step 2: Trap the foot under your armpit. Tuck the top of their foot deep under your armpit.
3. Step 3: Wrist on the Achilles. Set the bony thumb-side edge of your wrist on the Achilles, just above the heel, not up on the calf. Don’t reach too deep or the ankle ends up in your elbow crease.
4. Step 4: Lock your grip. Grab your own hand or wrist, or the collar in the gi, and keep your elbow tight to your ribs.
5. Step 5: Fall to your side. Fall to your side rather than flat on your back. In IBJJF, below brown belt, don’t turn towards their other foot.
6. Step 6: Push the hip and arch, slowly. Push their hip away with your foot, arch your back, drive your hips forward and pull your elbow back. Go slowly, and let go the moment they tap.

Common straight foot lock mistakes

• Wrist on the calf. Too high and the pivot is on the muscle, not the joint, so the lever is short. Slide down to just above the heel.
• Reaching too deep. If the ankle sits in your elbow crease, there’s no hard pivot. Keep the bony edge of the wrist on the Achilles.
• Leaning straight back. Lying back without arching does little. The finish comes from your hips driving forward.
• Leaving the knee free. Without control of their knee and hip, they sit up, step over or pull the foot out.

If the foot turns as they escape, the toe hold and the heel hook are close by, at the levels where they’re allowed.

What happens if you don’t tap to a straight foot lock?

You sprain the front of your ankle. The tendons and ligaments at the front and sides stretch, and they can tear. If the foot twists inwards on the way, the outside ankle ligament is the likely one, the same one you roll your ankle on (Hasegawa et al. 2026; Scoggin et al. 2014). Nobody has measured which structure goes first in a pure straight foot lock.

In a survey of 1,140 grapplers, 8 of the 46 ankle sprains reported came from straight foot locks (Hinz et al. 2021). Of everyone with an ankle sprain in that survey, 52% were back to normal activity within a month and 91% within three months. Most ankle sprains aren’t long lay-offs, but a sprain is still an injury, and repeated sprains can leave an ankle unstable or painful long term (Hasegawa et al. 2026).

How to train the straight foot lock safely

• Tap early. Tap when your foot is trapped and you feel the stretch over the front of the ankle, not when it hurts.
• Finish slowly and let go on the tap. Arch gradually so your partner has time to tap, and release the moment they do.
• Train under a qualified coach. Learn leg locks in a class, with someone who can check your position.
• Get checked if something’s wrong. Seek medical care for ankle pain, swelling, or an ankle that keeps giving way after a foot lock.

Does your foot lock land on everyone, or only on beginners?

Finishing a white belt and finishing a resisting blue belt are different results. JitsAI scores each technique against a nine-level ladder by partner size and experience, so you know who your foot lock really works on.

• One Focus a week, with pinned lessons from Henrique Rezende’s 74-lesson fundamentals course.
• A nine-level ladder for every technique, from partners less experienced than you to more experienced ones, each split lighter, same weight and heavier.
• Land it once and it’s a hit; 3 wins across 2 sessions and it’s proven.

Take the free 2-minute quiz →

$1 for 7 days, then $39 a year.
iPhone and Android.

Sound on

1. 1Pick ONE thing One position for the week: an escape, a guard, a sweep.

2. 2Test it on everyone A quick check-in after class: who each round was against, and whether it worked.

3. 3Hit, then proven Land it once and it’s a HIT. Three across two sessions and it’s PROVEN.

4. 4Know what works See what holds up, against whom, then pick your next Focus.

Video transcripts