How do I do a proper lunge?

Down, not forward — the single correction that fixes most lunges, plus the variations that suit different knees.

Difficulty: beginner
Time: 10 min
Read: 2 min
Safety: caution

Short answer

Drop straight down rather than pushing forward, with your front shin roughly vertical and your weight through the front heel. If your knee hurts, try a reverse lunge — stepping backwards is far kinder to the knee.

A lunge trains one leg at a time, which is how you actually walk and climb stairs, and it exposes side-to-side differences that a squat hides. Most of the discomfort people associate with it comes from moving forward instead of down.

Safety

Stop if you feel pain in the knee, hip or lower back — a lunge should be effortful but not painful. If you have a knee problem or poor balance, hold a wall or a chair, and get advice before loading the movement. General technique guidance, not treatment.

Step by step

Start from a split stance, not a step.Feet already apart, one forward one back, hip-width apart side to side. Learning the movement from a static position is much easier than stepping into it.
Keep your feet apart sideways.Not on a tightrope. Hip-width apart laterally gives you a stable base — most balance problems in a lunge come from placing the feet in line.
Drop straight down.The key correction. Think of lowering the back knee towards the floor rather than pushing the front knee forward. This alone fixes most knee discomfort.
Keep the front shin roughly vertical.The front knee stays above or just behind the ankle. Weight through the front heel and midfoot, not the toes.
Go as low as is comfortable.Back knee towards the floor, aiming for both knees at about a right angle. Depth comes with practice — do not force it.
Stay upright through the torso.Chest up, ribs down, core braced. Leaning forward shifts the load and is usually a sign the movement has become a step rather than a descent.
Push through the front heel to stand.Drive up through the front foot. Feeling it in the front thigh and glute is right.
Use a reverse lunge if the knee complains.Step backwards instead of forwards. It is easier to control, easier to balance, and considerably kinder to the front knee. A perfectly good permanent choice, not a lesser version.

Tips

Hold a wall or a chair while you learn. Balance improves quickly and there is nothing to prove by wobbling.
Most people are noticeably stronger on one side. That is normal — do the same number both sides and it evens out over months.
Reverse lunges suit most people better than forward ones. If forward lunges have always felt wrong, try stepping back instead.

Common mistakes

Pushing the front knee forward instead of dropping down — It loads the knee joint rather than the muscles and is the main cause of knee discomfort in a lunge.
Placing the feet in a straight line — It removes the lateral base and makes balance the limiting factor instead of strength.

Questions people ask

Why do lunges hurt my knees?

Usually because the movement is going forward rather than down. Drop the back knee towards the floor, keep the front shin vertical, and try a reverse lunge instead.

Are reverse lunges easier?

Easier to control and kinder to the front knee, and just as effective. It is a legitimate permanent choice rather than a beginner version.