Lunge: Your First Single-Leg Move

If you have never trained your legs on purpose, the lunge is a friendly place to begin. You step one foot forward, lower until your back knee is just off the floor, and push back to standing. That is the whole thing. It costs nothing, needs about two metres of floor, and most people can manage a few honest repetitions on their very first attempt. It is also the first rung of a ladder that keeps going for years, because every harder single-leg move you will ever train is this same shape with less help from the back leg.

What Is the Lunge?

A lunge is a split-stance squat. You stand tall, step one foot out in front of you, and bend both knees until the back one nearly touches the ground. Then you drive through the front heel and return to standing. The front leg does most of the work; the back leg is there for balance and for a share of the load.

In BodyTree it is the entry point of the Lunges and Step-Ups branch, the single-leg hip-dominant line that runs from here all the way to the deep step-up. That phrase sounds technical and means something simple: these are the exercises where one leg carries you, and where the hips and glutes drive the movement rather than the knees alone.

Why does one leg at a time matter when you could just do squats? Because almost everything you do outside training happens on one leg. Walking, stairs, standing up from the floor, catching your balance on a kerb. Two-legged squats let your stronger side quietly cover for your weaker one, and most beginners have a noticeable difference between sides without knowing it. A lunge makes that difference obvious in the first set, and then fixes it. It also asks your hip to stabilise sideways, which a squat barely does, and that stability is what keeps knees comfortable over a lifetime of training.

The other reason to start here is honesty about equipment. You do not need a bar, a bench, rings, or a pull-up hook. You need a floor. That makes the lunge one of the few strength exercises nobody has a real excuse to postpone.

Prerequisites

There are no strength prerequisites. If you can walk up a flight of stairs without holding the rail, you have enough to start lunging today. This is a level 1 movement, which is the system's way of saying it is a beginning, not a reward you earn later.

Two practical notes instead of prerequisites. First, balance is allowed to be a work in progress. Wobbling is not a sign you are unready, it is the movement teaching your hip how to hold a line, and it settles down within a couple of weeks. If you feel unsteady, stand beside a wall, a doorframe, or the back of a chair and rest one or two fingertips on it. Fingertips, not a grip, so the leg still does the work.

Second, if the back knee touching down is uncomfortable, fold a towel or a cushion on the floor under it. Trusted calisthenics references are consistent on this point: comfort modifications do not make an exercise less effective, and people who are comfortable train more often than people who are not.

If you cannot yet lower all the way, lower as far as you can control and come straight back up. Half a range you own is worth more than a full range you fall through, and the range grows quickly.

The Progression Chain

Every step on this branch does one of two things: it takes support away from the back leg, or it raises the height the front leg has to lift you through. That is the entire logic of the chain, and knowing it means you can always tell what the next step is actually asking of you.

Lunge. Both feet on the floor, back leg helping. Where you are now.

Stair Step-Up. You step up onto a single stair and lower yourself back down under control, with no bounce off the trailing foot. It is a modest height on purpose. This is where you learn to stand up using one leg only, which is the skill the rest of the branch is built on.

Chair Lunge. The same lunge as before, but with your back foot raised on a chair behind you. Lifting the back foot shifts most of your weight onto the front leg, so the load goes up without anything being added. It doubles as a good stretch for the front of the hip on the raised side.

Chair Step-Up. A step-up onto chair height, started from a dead stop with no push from the trailing foot. Now the front leg is lifting your whole body through a deep bend. Most people meet their first real sticking point here, and the fix is patience with the height rather than a new exercise.

Deep Step-Up. Starting with the working thigh below parallel and standing all the way up onto a high surface. This is the strongest hip-dominant single-leg movement available without adding weight, and it is a genuinely impressive thing to own.

Notice there is no leap in this chain. Each rung is the previous one with a bit more height or a bit less help, which is why nobody needs to guess when they are ready.

Sets, Reps, and Frequency

The BodyTree standard for a concentric exercise like this one is 3 sets of 15 repetitions per leg. Hitting it unlocks the stair step-up. Treat it as a target you walk towards rather than a gate you are locked behind: plenty of beginners start at 6 or 8 solid repetitions a side and reach 15 inside a month.

Two or three sessions a week is right, with a day in between. Legs recover well, but the goal of your first weeks is repetition of the habit, not soreness. If you are already squatting, put the lunges in the same session rather than inventing a separate leg day that will not survive a busy week.

Rest 60 to 90 seconds between sets, or however long it takes for your breathing to settle. Do all the repetitions on one leg, then swap, and always start with your weaker side so it sets the number for both. That one habit is how a side-to-side difference closes instead of widening.

When 3 sets of 15 starts to feel easy, resist the temptation to chase 30. Long sets of an easy movement build endurance, not strength. Add difficulty instead: pause for two seconds at the bottom of every repetition, lower over a slow three-count, or move on to the stair step-up. Harder, not longer, is the rule for this whole branch.

Coaching Cues

• Step out far enough that the front shin stays vertical. A short step drives your knee way past your toes and loads it hard. A longer step keeps the shin upright and hands the work to the hip and glute, which is what you want.
• Lower until the back knee is just off the floor. That gives you a consistent depth to measure against, so you can tell whether this week is better than last week.
• Drive through the front heel with no momentum. You should be able to lift your front toes slightly and still finish the repetition. If you have to rock or bounce out of the bottom, the set is over.
• Keep the knee tracking over the foot. The front knee should point the same way the front toes point. A knee that collapses inwards is a hip that is not holding its line, and the answer is a slower tempo and a little more practice, not a brace.
• Stay tall through the torso. Chest up, ribs down, eyes forward. Leaning forward to reach the floor turns a leg exercise into a balancing act.
• Breathe in on the way down, out on the way up. Holding your breath is the quickest way to feel light-headed on the fifth repetition.

Common Mistakes

• Letting the back leg do the pushing. This is the big one. If you shove off the back foot, you have turned a single-leg exercise into a two-leg one and the chain stops progressing. Think of the back leg as a kickstand, not an engine. If the repetitions get much harder when you stop pushing with it, that is exactly the weakness worth training.
• Stepping too short. The most common cause of a lunge that bothers the knee. Step further out and the discomfort usually disappears in the same session.
• Crashing the back knee into the floor. Tapping the ground hard is not depth, it is a landing. Lower under control and stop just short of contact.
• Training only your strong side to a number. Doing 15 on the good leg and 9 on the other, then calling it 15, preserves the difference forever. Match the weaker side and let it lead.
• Adding repetitions instead of difficulty. Sets of 40 lunges feel productive and build very little strength. Move up the chain instead.
• Quitting because you wobble. Balance is a trained skill, not a talent. Use a fingertip on a wall for a fortnight and it goes away.

Related Guides

• Bodyweight Squat
• Glute Bridge
• Parallel Squat
• Sit-to-Stand

Frequently Asked Questions

Are lunges good for beginners?

Yes. The lunge is a level 1 movement that needs no equipment and no prior training. It is the entry point of the single-leg branch, and a beginner can usually perform several controlled repetitions on the first attempt.

How many lunges should a beginner do?

Aim for 3 sets of 15 repetitions per leg, two or three times a week. Starting at 6 to 8 repetitions a side is completely normal, and most people reach 15 within a month of consistent practice.

Why do my knees hurt when I lunge?

The usual cause is stepping too short, which pushes the front knee far past the toes. Take a longer step so the front shin stays vertical, lower more slowly, and keep the knee tracking over the foot rather than drifting inwards.

What comes after the lunge?

The stair step-up, where you stand up onto a single stair using one leg with no push from the trailing foot. After that come the chair lunge, the chair step-up, and the deep step-up.