Form guide · Lunge
How to Do a Proper Lunge
Lunges build single-leg strength and balance that two-legged moves can't — but only if you actually sink into them. Most people stop way too high.
Lunges expose imbalances a squat can hide: one leg working at a time, your balance and stability genuinely challenged. That's the value — and it's why people shy away from the full range, taking shallow, tentative steps instead of real reps.
Done properly, a lunge sends your front thigh to roughly parallel with the floor and your front knee to about 90°. This guide covers stride length, knee position, balance, and the mistakes that quietly shorten the movement.
How to do it, step by step
- 1
Set your stance
Stand tall with feet hip-width apart and your core braced. Take a controlled step forward — long enough that both knees can reach about 90° at the bottom.
- 2
Lower straight down
Drop your hips straight down rather than lunging forward. Your torso stays upright with a slight natural forward lean from the hips.
- 3
Hit depth
Lower until your front thigh is roughly parallel to the floor and your front knee is at about 90°. Your back knee should drop toward the floor, hovering just above it.
- 4
Track your front knee
Keep your front knee pointing in line with your foot — not caving inward — and your weight balanced through the whole front foot.
- 5
Drive back up
Push through your front heel to return to standing under control. Finish tall before stepping into the next rep, then switch legs.
What Tip Top's AI checks
Front knee bent to about 90° at the bottom = a full-depth rep. Barely dipping = shallow.
Tip Top Fitness's AI measures your front-leg knee angle (hip–knee–ankle) and finds the deepest point of each rep. If your knee never bends past roughly 125° — meaning you only dipped a little — it logs the rep as shallow, and after a couple in a row your coach cues you to bend the front knee deeper toward 90°. It automatically works out which leg is forward, so it tracks alternating lunges without any setup.
Try a form check freeMuscles worked
Primary
- Quadriceps
- Glutes
Supporting
- Hamstrings
- Calves
- Core
Common mistakes (and how to fix them)
Not lunging deep enough
The most common lunge mistake: a shallow dip that barely bends the front knee. Aim for the front thigh near parallel and the knee around 90°. If balance is the limiter, hold onto something light for support while you build the range.
Front knee caving inward
Letting the front knee collapse toward the midline stresses the joint and signals weak glutes. Cue the knee to track in line with your toes throughout the rep.
Leaning the torso too far forward
Pitching your chest down toward your front thigh shifts load off the legs and onto your lower back. Keep your torso fairly upright with only a slight hinge from the hips.
Stride too short
A short step forces your front knee far past your toes and turns the lunge into a quad-only, knee-heavy movement. Take a longer step so both knees can reach about 90° comfortably.
Why it's worth training
- Builds single-leg strength and corrects left-to-right imbalances a squat can mask.
- Trains balance and stability through the hips, knees, and ankles.
- Highly functional — it mirrors walking, climbing, and lunging movements in daily life.
- Scales easily from bodyweight to dumbbells without needing a rack.
Frequently asked questions
How deep should a lunge go?
Lower until your front thigh is roughly parallel to the floor and your front knee is at about 90°, with your back knee dropping toward the floor. Stopping well short of that is the most common way people undertrain the movement.
Is it OK for my knee to go past my toes in a lunge?
A little is fine and often unavoidable. What matters more is that your front knee tracks in line with your foot and you're not collapsing inward. If your knee shoots far past your toes, lengthen your stride.
Why do I lose my balance during lunges?
Lunges genuinely challenge stability because you're on one leg. Slow the rep down, fix your eyes on a point ahead, brace your core, and use a light handhold for support while you build control. Balance improves quickly with practice.
Forward or reverse lunges — which is better?
Both are effective. Reverse lunges are often easier on the knees and simpler to balance, which makes them a great starting point; forward lunges add a bit more deceleration demand. Use whichever lets you reach full depth with good knee tracking.
Stop guessing about your lunge form.
Tip Top Fitness watches every rep through your phone camera, counts them, and tells you the one thing to fix — in real time.
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