Lateral lunge: the step, what changes from a forward lunge, and what it trains

A lateral lunge, or side lunge, is a lunge done to the side. You step wide, bend the leg you stepped onto and sit your hips back over it while the other leg stays nearly straight, then push back to where you started. A forward lunge moves you front to back; this one moves you side to side.

This page covers the step, what one study measured when it put the lateral and the forward lunge side by side, what the lateral lunge trains, how to hold a weight, the faults, and the sets. The forward, reverse and walking lunges are on how to do lunges, and the version with the back foot on a bench is the Bulgarian split squat.

How to do a lateral lunge

1. Stand tall with your feet together or hip-width apart, toes forward, hands together in front of your chest.
2. Step wide to one side. In one study the standard step was 60% of each person's height, and the step people picked for themselves to the side wasn't significantly different from it.¹ In practice, step wide enough that you can sit back with the whole foot flat.
3. Sit back over the stepping leg. Bend that knee, push your hips back, keep your chest up and your knee in line with your toes. The other leg stays straight, its foot flat on the floor.
4. Push back to the start through the whole foot of the bent leg, and bring your feet together again.
5. Finish the reps on one side, or alternate, and give the other side the same number.

Lateral lunge vs forward lunge: what was measured

One study had 32 young adults (16 men and 16 women) do six lunges in each direction, at a step length they picked and at a standard step of 60% of their height. It measured how far the ankle, knee and hip of the stepping leg bent:¹

• The ankle bent more in the lateral lunge: 83.5% more at the standard step and 55.3% more at the step people chose.
• The knee bent a little more in the forward lunge: 12.8% more.
• The hip: no significant difference in how far it bent.

From the measured movement, the study also calculated how much the extensor muscles at each joint contributed. In the lateral lunge more came from the knee and the ankle; in the forward lunge more came from the hip.¹ Those are calculations, not direct measurements of the muscles. A study of 20 older adults, average age 75, calculated a similar split: the forward lunge leaned on the muscles that straighten the hip, the lateral lunge on the calf muscles that point the foot, and the knee results were less consistent.²

What that means in a session, as practical advice rather than a finding: the lateral lunge needs more ankle bend, so if your heel lifts when you sit back, take a slightly narrower step until it stays down. If the hips are the goal, both studies calculated more of the demand at the hip in the forward lunge.

What the lateral lunge trains

• The front of the thigh much more than the hamstrings. In 27 active young adults (12 men and 15 women), front-thigh activity divided by hamstring activity was 9.3 in the lateral lunge, one of the three highest of the nine exercises tested, beside the forward lunge (9.7). In a single-leg deadlift it was 2.9.³ So the lateral lunge is not a hamstring exercise; the single-leg Romanian deadlift covers that side.
• The inner thigh and the inner front thigh, in a training trial. In a six-week trial, 27 young male team-sport players trained twice a week on a flywheel machine built to overload the lowering: 14 did lateral lunges, one leg at a time, and 13 did half squats. Measured by MRI, the lateral-lunge group grew the vastus medialis, the inner muscle of the front thigh, by about 13% and the adductor magnus, the large inner-thigh muscle, by about 11%, more than the squat group did, though the squat group's vastus medialis grew too, by about 11%. The squat group grew the outer front thigh and one calf muscle more.⁴

That trial used a flywheel, not dumbbells, and men who already trained three or four times a week.⁴ No trial of dumbbell lateral lunges turned up in the search for this page, so it makes no claim about what weeks of them build. For the inner thigh on its own, the hip adduction machine is the other route.

Holding a weight

None of the studies above compared ways of holding a load, so this is practical advice. The easiest hold is one dumbbell or kettlebell held at your chest, as in the goblet squat: it stays out of the way of the bent leg. Next is a dumbbell in each hand, arms hanging. Start with bodyweight until you can sit back with the foot flat for 10 reps a side, then add a light weight.

The common faults, and a fix for each

• The knee caving in. Keep the bent knee in line with your toes.
• The heel lifting. Take a narrower step, or sit back less deep, until the foot stays flat.
• Bending the straight leg. The leg you didn't step with stays straight; if it bends, you've turned it into a squat.
• Rounding forward. Hips back, chest up, as if you were sitting onto a low box behind you.
• A step too short to sit back into. Step wide enough that the hips can travel back, not just down.
• Lunging through pain. If you have pain, an injury or a medical condition, stop and ask a doctor or a physical therapist.

Sets, reps and where it goes

• What the trial used: 4 sets of 7 reps per leg, with three minutes between sets, twice a week with at least 48 hours between sessions, for six weeks, on the flywheel machine.⁴
• As a practical start: 2 or 3 sets of 8 to 12 per side, two or three reps short of failure, as the second or third exercise of a leg day. This is practical advice, not a finding. How to judge reps left.
• Where it fits: after a squat or a hinge, in the single-leg slot, or alongside forward lunges on a leg day. A few slow bodyweight reps also suit a warm-up.

Common questions

Lateral lunge vs side lunge?

Same exercise, two names.

Do lateral lunges work the inner thighs?

In the one training trial found, yes: on a flywheel machine, six weeks of lateral lunges grew the large inner-thigh muscle, the adductor magnus, by about 11%, more than half squats did.⁴ That was one small trial in trained young men.

Can I do lateral lunges at home?

Yes. Bodyweight needs only floor space to the side; a backpack held at the chest adds load once 10 slow reps a side feel easy. That is practical advice, not a finding.

If you'd rather not plan it alone

A lateral lunge takes a few sets to learn; deciding where it sits beside your squats, forward lunges and the rest of your leg work is the part a page can't do. Coaching is the version where your workouts are built around the days you actually have, and a weekly call looks at the week you just had and rebuilds the next one. Coaching for beginners explains how that works, and here's how to apply. Otherwise: at your next leg session, do two sets of ten lateral lunges a side with bodyweight, and write down how deep you could sit with the foot flat.