{"schemaVersion":1,"id":"en-movement-lunge","type":"movement","pillar":"movement","locale":"en","translationGroupId":"movement-lunge","slugPath":"movements/lunge","title":"Lunge","shortTitle":"Lunge","summary":"The lunge is a staggered stance: one leg forward, one behind, and a body descending between the two. That deliberate imbalance is what sets it apart from the squat.","level":"beginner","estimatedMinutes":8,"synonyms":["lunge","forward lunge","reverse lunge","split squat","unilateral movement","staggered stance"],"blocks":[{"id":"b1","type":"heading","level":2,"text":"What the lunge is for","anchor":"what-the-lunge-is-for"},{"id":"b2","type":"paragraph","content":[{"kind":"text","value":"The "},{"kind":"link","value":"squat","href":"/en/movements/squat","external":false},{"kind":"text","value":" shares the load across two symmetrical supports. The lunge puts one foot in front, one behind, and lowers the body between them. The difference is not only one of range: it changes the nature of the problem the body has to solve."}]},{"id":"b3","type":"paragraph","content":[{"kind":"text","value":"In a squat, the body has to produce force. In a lunge, it has to produce force "},{"kind":"emphasis","value":"and"},{"kind":"text","value":" hold a sideways balance that nothing guarantees. That second task calls on muscles which, in the squat, stay in the background."}]},{"id":"b4","type":"definition","term":"Unilateral stance","definition":"A configuration in which the two feet are neither side by side nor loaded the same way. The base of support becomes narrow from side to side, and controlling the pelvis in that plane becomes a constraint in its own right.","alsoKnownAs":["staggered stance"]},{"id":"b5","type":"heading","level":2,"text":"The phases of the movement","anchor":"the-phases-of-the-movement"},{"id":"b6","type":"timeline","title":"The lunge, phase by phase","steps":[{"id":"t0","label":"Starting position","timing":"0 s","description":"Staggered stance, weight split between the ball of the back foot and the whole front foot."},{"id":"t1","label":"Descent","timing":"eccentric phase","description":"Front hip and knee flex, the back knee travels towards the floor; the muscles brake while lengthening."},{"id":"t2","label":"Bottom position","timing":"transition","description":"The trunk is close to vertical, the pelvis low; sideways control is most loaded here."},{"id":"t3","label":"Rise","timing":"concentric phase","description":"Extension of the front hip and knee, pushing into the floor; the body rises without the pelvis giving way sideways."}]},{"id":"b7","type":"heading","level":2,"text":"Joints and planes of movement","anchor":"joints-and-planes-of-movement"},{"id":"b8","type":"paragraph","content":[{"kind":"text","value":"The lunge moves the same joints as the squat — hip, knee, ankle — but adds a constraint in a plane the squat barely loads."}]},{"id":"b9","type":"list","ordered":false,"items":[[{"kind":"strong","value":"Sagittal plane"},{"kind":"text","value":": flexion and extension of hip and knee, as in the squat. That is the visible movement."}],[{"kind":"strong","value":"Frontal plane"},{"kind":"text","value":": the pelvis tends to drop towards the back leg, which carries less load. Controlling that drop is what sets the lunge apart."}],[{"kind":"strong","value":"Transverse plane"},{"kind":"text","value":": the femur of the front leg tends to turn inwards; the hip rotators resist that."}]]},{"id":"b10","type":"heading","level":2,"text":"Who does the work","anchor":"who-does-the-work"},{"id":"b11","type":"comparison","title":"Muscle roles in the lunge","columns":["Role","Front leg","Back leg"],"rows":[{"label":"Prime mover","cells":["Quadriceps and gluteus maximus","Modest share of extension"]},{"label":"Frontal stabilisation","cells":["Gluteus medius and adductors","Adductors, holding back"]},{"label":"Pelvic control","cells":["Erector spinae and abdominal wall","Iliopsoas, stretched by the open hip"]},{"label":"Ankle control","cells":["Tibialis anterior and calf","Calf, in a lengthened position"]}]},{"id":"b12","type":"paragraph","content":[{"kind":"text","value":"Two muscles described elsewhere take on an importance here that they lack in the squat. The "},{"kind":"link","value":"hip adductors","href":"/en/body/muscles/hip-adductors","external":false},{"kind":"text","value":" control sideways movement of the pelvis, a task that becomes central as soon as the base narrows. The "},{"kind":"link","value":"iliopsoas","href":"/en/body/muscles/iliopsoas","external":false},{"kind":"text","value":" of the back leg ends up in a lengthened position, with the hip open: it is that position, not any deliberate stretch, that explains the sensation felt at the front of the rear thigh."}]},{"id":"b13","type":"evidence","level":"established","statement":"Knee flexion under load distributes stress between the patellofemoral joint and the structures of the knee, according to the angle reached and the trunk position.","detail":"Reference kinesiology and work on squat biomechanics describe that distribution. Transferring it to the lunge is reasonable for the joint itself, less so for the split between the two legs, which that work does not study.","referenceIds":["neumann2016","escamilla2001"]},{"id":"b14","type":"evidence","level":"probable","statement":"Trunk control contributes to force transmission in movements on a reduced base of support.","detail":"The review on core training describes the role of the muscles framing the spine in transmitting force between lower and upper limbs. The size of their contribution in a lunge specifically is not established separately, and depends on load, speed and range.","referenceIds":["mcgill2010"]},{"id":"b15","type":"heading","level":2,"text":"What body proportions change","anchor":"what-body-proportions-change"},{"id":"b16","type":"paragraph","content":[{"kind":"text","value":"The relative length of femur and tibia markedly changes what is reachable. A long femur requires a longer step to reach the same depth, which tips the trunk further forward and shifts the demand towards the hip. The available ankle dorsiflexion range sets how far the front knee can travel."}]},{"id":"b17","type":"paragraph","content":[{"kind":"text","value":"These variations are anatomical, not technical. A position achieved by someone whose segments are proportioned differently is no benchmark."}]},{"id":"b18","type":"heading","level":2,"text":"Common misreadings","anchor":"common-misreadings"},{"id":"b19","type":"callout","tone":"caution","title":"Three beliefs about the lunge","content":[[{"kind":"strong","value":"That it is a squat on one leg."},{"kind":"text","value":" The difference lies in the frontal plane: the lunge demands sideways control that the squat does not. The muscles involved are not merely fewer, they are not the same."}],[{"kind":"strong","value":"That the knee should never pass the toes."},{"kind":"text","value":" How far the knee travels depends on the available ankle range and on segment lengths. The load shifts between joints; it does not disappear if you prevent that travel."}],[{"kind":"strong","value":"That the sensation at the front of the rear thigh is a stretch to chase."},{"kind":"text","value":" It comes from the open position of the hip. This page describes what happens; it does not say what should be done."}]]},{"id":"b20","type":"heading","level":2,"text":"Seeing the movement","anchor":"seeing-the-movement"},{"id":"b21","type":"scene3d","sceneId":"quadriceps-squat","title":"Quadriceps and squat","intro":"The scene shows the quadriceps working during a loaded knee bend. The lunge calls on the same prime movers in the front leg, adding a sideways control the scene does not depict. Without the 3D, the essentials fit in one sentence: knee and hip close on the way down and open on the way up, on a narrow base.","accessibility":{"textAlternative":"A three-dimensional diagram of the lower half of the body, standing, seen from the front: pelvis, femurs, tibias and patellae are shown in bone tones, with the feet and a reference trunk in a neutral paper shade. On each thigh the four heads of the quadriceps are laid over in terracotta and stay distinct: rectus femoris in the middle, vastus lateralis on the outside, vastus medialis on the inside, and the deeper vastus intermedius against the femur. Behind, the glutes cap the pelvis and the calves fill the upper shank. A three-second animation flexes the ankle, knee and hip together: the knee travels forward over the foot, the hip moves back and down, the trunk leans, and then the movement reverses. The volumes are stylised: this is a teaching diagram, not an exact anatomical reconstruction.","structures":[{"label":"Rectus femoris","description":"The only head of the quadriceps to cross two joints: it arises from the anterior inferior iliac spine of the pelvis and runs down the middle of the thigh into the quadriceps tendon. It extends the knee and flexes the hip.","href":"/en/body/muscles/quadriceps"},{"label":"Vastus lateralis","description":"The largest of the four heads, arising from the greater trochanter and the linea aspera on the outer side of the femur. It acts on the knee alone, extending it, and gives the thigh its outer contour.","href":"/en/body/muscles/quadriceps"},{"label":"Vastus medialis","description":"The inner head, arising from the linea aspera of the femur, whose lowest fibres reach the patella almost horizontally. It extends the knee and helps keep the patella tracking in line.","href":"/en/body/muscles/quadriceps"},{"label":"Vastus intermedius","description":"The deep head, pressed against the front of the femur and covered by the other three. Invisible from the outside, it still produces a substantial share of knee extension.","href":"/en/body/muscles/quadriceps"},{"label":"Patella","description":"A sesamoid bone embedded in the quadriceps tendon, which continues as the patellar tendon onto the tibial tuberosity. By holding the tendon away from the knee axis, it increases the lever arm of the quadriceps.","href":"/en/movements/squat"},{"label":"Glutes","description":"Arising from the iliac wing and the sacrum, inserting on the femur and the iliotibial tract. In the squat they extend the hip: the more the trunk leans forward, the larger their share of the work compared with the quadriceps.","href":"/en/body/muscles/glutes"},{"label":"Calves","description":"The gastrocnemius and soleus, joining on the calcaneus through the Achilles tendon. In the squat they work mostly as brakes, controlling ankle dorsiflexion and therefore how far the knee travels forward.","href":"/en/body/muscles/calves"}],"steps":[{"id":"charpente","title":"Three segments, three joints","body":"The squat is not a thigh movement: it is a sequence. Pelvis, femur and tibia form three segments linked by the hip, the knee and the ankle, with the patella sitting in front of the knee. The whole mechanics of the movement lives in those pivots."},{"id":"quatre-chefs","title":"The four heads of the quadriceps","body":"Rectus femoris occupies the middle of the thigh, vastus lateralis its outer border, vastus medialis its inner border, and vastus intermedius hides beneath them against the femur. All four converge on a single tendon: they pull together, but only rectus femoris also crosses the hip."},{"id":"rotule-poulie","title":"The patella as a pulley","body":"The quadriceps tendon wraps around the patella and continues to the tibial tuberosity. By holding the tendon away from the axis of flexion, the patella lengthens the lever arm — that is what makes knee extension effective in the bottom position."},{"id":"descente","title":"The coordinated descent","body":"Ankle, knee and hip flex together. The ankle lets the knee travel forward over the foot, the femur tips backwards, and the trunk leans to keep balance over the midfoot. The quadriceps first brakes the descent, then drives the way back up."},{"id":"partenaires","title":"What the rest of the leg does","body":"The glutes extend the hip and take on more work the further the trunk leans; the calves restrain the ankle and steady the base. The quadriceps is the most heavily loaded engine in the squat, but it does not decide the depth reached on its own."}],"license":"Z-Anatomy et BodyParts3D — CC-BY-SA 4.0"}},{"id":"b22","type":"heading","level":2,"text":"Related movements and structures","anchor":"related-movements-and-structures"},{"id":"b23","type":"paragraph","content":[{"kind":"text","value":"The lunge reads alongside the "},{"kind":"link","value":"squat","href":"/en/movements/squat","external":false},{"kind":"text","value":", which shares its prime movers, and the "},{"kind":"link","value":"hip hinge","href":"/en/movements/hip-hinge","external":false},{"kind":"text","value":", which splits the work between hip and knee differently. On the structural side it involves the "},{"kind":"link","value":"quadriceps","href":"/en/body/muscles/quadriceps","external":false},{"kind":"text","value":", the "},{"kind":"link","value":"glutes","href":"/en/body/muscles/glutes","external":false},{"kind":"text","value":", the "},{"kind":"link","value":"hip adductors","href":"/en/body/muscles/hip-adductors","external":false},{"kind":"text","value":" and "},{"kind":"link","value":"tibialis anterior","href":"/en/body/muscles/tibialis-anterior","external":false},{"kind":"text","value":"."}]},{"id":"b24","type":"heading","level":2,"text":"Sources","anchor":"sources"},{"id":"b25","type":"sourceList","title":"Main sources","referenceIds":["neumann2016","standring2020","escamilla2001","mcgill2010"]},{"id":"b26","type":"shapierAction","actionId":"exercises-forward-lunge","label":"See the forward lunge in Shapier","description":"Performing the forward lunge and building it into a session happens in Shapier; Body Lab only explains how this movement works.","webTarget":"https://shapier.app/en/exercises/forward-lunge","appTarget":"shapier://exercises/forward-lunge"},{"id":"b27","type":"quiz","title":"Check my understanding","questions":[{"id":"q1","prompt":"What truly sets the lunge apart from the squat?","choices":[{"id":"q1c1","label":"It adds sideways pelvis control in the frontal plane, which the squat does not demand.","correct":true,"explanation":"The base becomes narrow from side to side and the pelvis tends to drop towards the back leg: the stabilising muscles are not the same as in the squat."},{"id":"q1c2","label":"It is a squat on one leg, with fewer muscles involved.","correct":false,"explanation":"The page corrects this belief: the muscles involved are not merely fewer, they are not the same."},{"id":"q1c3","label":"The difference is mainly one of range of motion.","correct":false,"explanation":"The difference is not only one of range: it changes the nature of the problem the body has to solve."}]},{"id":"q2","prompt":"What does this page say about the front knee travelling past the toes?","choices":[{"id":"q2c1","label":"It depends on the available ankle range and on segment lengths.","correct":true,"explanation":"Ankle dorsiflexion sets how far the knee can travel, and femur and tibia lengths change the position reached."},{"id":"q2c2","label":"It should always be avoided, because it removes the load on the knee.","correct":false,"explanation":"It is the opposite: preventing that travel does not make the load disappear, it shifts it between joints."},{"id":"q2c3","label":"It is a technical benchmark that looks the same for everyone.","correct":false,"explanation":"These variations are anatomical, not technical: a position achieved with differently proportioned segments is no benchmark."}]},{"id":"q3","prompt":"Where does the sensation at the front of the rear thigh come from during a lunge?","choices":[{"id":"q3c1","label":"From the lengthened position of the iliopsoas, with the back hip open.","correct":true,"explanation":"It is the open position of the hip that puts the iliopsoas under tension, not any deliberate stretch."},{"id":"q3c2","label":"From a stretch to be chased deliberately during the movement.","correct":false,"explanation":"The page corrects this belief: the sensation comes from the position, and the page does not say it should be chased."},{"id":"q3c3","label":"From the calf of the back leg, held in a lengthened position.","correct":false,"explanation":"The back calf is indeed lengthened, but the sensation at the front of the thigh comes from the iliopsoas, on the other side of the leg."}]}]},{"id":"b28","type":"relatedContent","title":"Read next","targetIds":["en-movement-squat","en-anatomy-hip-adductors","en-movement-hip-hinge"]}],"relations":[{"type":"uses-structure","targetId":"en-anatomy-quadriceps"},{"type":"uses-structure","targetId":"en-anatomy-glutes"},{"type":"uses-structure","targetId":"en-anatomy-hip-adductors"},{"type":"uses-structure","targetId":"en-anatomy-iliopsoas"},{"type":"next-step","targetId":"en-movement-squat"}],"authors":["equipe-editoriale-shapier"],"reviewers":["Thanh Chau"],"references":[{"id":"neumann2016","authors":"Neumann DA","year":2016,"title":"Kinesiology of the Musculoskeletal System: Foundations for Rehabilitation, 3rd edition","source":"Elsevier","kind":"book","url":"https://shop.elsevier.com/books/kinesiology-of-the-musculoskeletal-system/neumann/978-0-323-28753-1"},{"id":"standring2020","authors":"Standring S","year":2020,"title":"Gray's Anatomy: The Anatomical Basis of Clinical Practice, 42nd edition","source":"Elsevier","kind":"book","url":"https://shop.elsevier.com/books/grays-anatomy/standring/978-0-7020-7705-0"},{"id":"escamilla2001","authors":"Escamilla RF","year":2001,"title":"Knee biomechanics of the dynamic squat exercise","source":"Medicine and Science in Sports and Exercise","kind":"journal-article","doi":"10.1097/00005768-200101000-00020"},{"id":"mcgill2010","authors":"McGill SM","year":2010,"title":"Core training: evidence translating to better performance and injury prevention","source":"Strength and Conditioning Journal","kind":"review","doi":"10.1519/ssc.0b013e3181df4521"}],"review":{"publishedAt":"2026-08-02","reviewedAt":"2026-08-02","reviewDueAt":"2027-08-02","evidenceLevel":"established"},"limitations":["The descriptions apply to a lunge with vertical load at controlled speed: a jumping or travelling lunge distributes the loads differently.","The knee biomechanics cited come from work on the squat: transferring it to the lunge is reasonable for the joint itself, less so for the split between the two legs.","Segment proportions markedly change the range reached and the trunk position. No position is described here as correct or incorrect.","This page explains a movement, it assesses no execution: pain that returns every session belongs to a health professional."],"seo":{"title":"Lunge — staggered stance, joints and muscles involved","description":"Phases of the movement, how work splits between the two legs, the role of the adductors and psoas, and what really separates the lunge from the squat.","canonicalPath":"/en/movements/lunge","image":"/og/en/movement-lunge.png"},"app":{"offlineEligible":true},"version":1}