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Single-Leg Sit-to-Stand

Draftstrength55%advanced⬤ moderate evidence
View FHIR resourceFHIR R4 ActivityDefinition — the interoperable form of this exercise

Why Include This

Sit-to-stand is one of the best-validated functional exercises for the lower limb: performance on timed sit-to-stand tests (5-times STS, 30-second STS) reliably reflects lower-extremity strength and power and predicts fall risk in older adults, and progressive sit-to-stand training has been shown to improve leg strength, functional mobility, and gait in older and deconditioned populations. Loading a single leg substantially raises the demand on the quadriceps and hip extensors and exposes side-to-side asymmetry, which is directly relevant after knee or hip injury/surgery and for anyone who struggles to rise from low seats or climb stairs. Direct randomized evidence specifically for the single-leg variant is limited, so this is best framed as a targeted progression of a well-supported movement: the bilateral sit-to-stand evidence is moderate, and the unilateral overload rationale (closed-chain, task-specific quadriceps and gluteal strengthening with a built-in range limit) is mechanistically sound and easily dosed at home.

Evidence basis: moderate

Positions & Range of Motion

Start
seated tall at the front edge of a wall-braced chair, working foot flat and slightly behind the knee, opposite leg lifted off the floor, trunk upright
End
fully upright standing on the single stance leg with hip and knee extended, non-stance leg still elevated
Range of Motion
stance-limb concentric extension from ~90° hip and knee flexion to full extension, then controlled eccentric return; forward trunk hinge (nose over toes) to load and unload

How to Perform

Sit on the front edge of a sturdy chair, extend one leg out in front, and stand up using only the planted leg, then lower back down under control. The chair provides a safe target and depth guide; keep it against a wall so it cannot slide.

Watch on YouTube↗

Opens a YouTube search for “Single-Leg Sit-to-Stand”

Equipment:chairwall
Starting position: seated

Coaching Cues

  1. 1

    Sit tall at the front edge of the chair, plant the working foot flat and slightly behind the knee, and lift the other leg off the floor.

    (setup)
  2. 2

    Hinge forward from the hips (nose over toes) to load the stance leg, then drive through the whole foot to stand.

    (external-focus)
  3. 3

    Keep your kneecap tracking over your second toe - do not let the knee collapse inward.

    (alignment)
  4. 4

    Lower slowly for a count of three, tapping the chair lightly rather than dropping onto it.

    (tempo)

Evidence-Based Dosing & EMG Data

Recommended Dosing

3 sets of 5-8 controlled reps per leg, 2-3 days per week, with a 2-3 second lowering phase; rest ~60-90 seconds between sets. Progress by lowering seat height, adding external load, or shifting to eccentric-only reps as strength and control improve.

Muscles Involved (14)

Primary Movers

Quadriceps Femoris— Concentrically extends the knee to stand and eccentrically controls the lowering back to the chair; principal mover of the single stance leg.
Gluteus Maximus— Primary hip extensor driving the stance leg to upright.
Vastus Medialis— Knee extensor important for terminal extension and patellar tracking on the single stance leg.
Vastus Lateralis— Major knee extensor contributing much of the extension force.
Vastus Intermedius— Deep knee extensor working with the other vasti.

Stabilizers

Transversus Abdominis— Provides core/trunk stability during the loaded transition.
Soleus— Controls the tibia over the foot for ankle/balance stability throughout the movement.
Tibialis Anterior— Maintains forward tibial control and balance over the stance foot during single-leg loading.
Erector Spinae Group— Keeps the trunk upright and controls the forward lean needed to rise.
Gluteus Medius— Controls frontal-plane pelvis/hip position and prevents knee valgus on the single stance leg — heightened demand in the unilateral variant.
Gluteus Minimus— Assists gluteus medius in hip/pelvis stabilization during single-leg loading.

Synergists & Assistors

Hamstrings (Group)Synergist— Assist hip extension and resist anterior tibial shear at the knee during the rise.
Adductor MagnusSynergist— Ischiocondylar (hamstring) portion assists hip extension from the flexed start position.
Rectus FemorisSynergist— Biarticular; assists knee extension but slackened at the flexed hip in the seated start, so it contributes less than the vasti.

Easier Variations ↓

1

Assisted single-leg sit-to-stand

Use fingertips on a countertop, wall, or the chair arms to share load and help balance, reducing the demand on the stance leg.

2

Higher seat / partial single-leg

Raise the seat with a firm cushion or use a taller chair so the range and load are smaller; progress the height down over time. Bilateral sit-to-stand is the full regression if single-leg is not yet possible.

Harder Variations ↑

1

Eccentric-focused (lower-only) single-leg

Stand on two legs, then lower to the chair slowly on one leg over 4-5 seconds to emphasize eccentric quadriceps and gluteal control.

2

Weighted or lower-seat single-leg

Hold a dumbbell, kettlebell, or loaded backpack at the chest, and/or lower the seat height to increase range and force demand.

Target Movements (5)

Knee ExtensionTibiofemoral Joint
Hip ExtensionHip Joint (Coxofemoral)
Knee FlexionTibiofemoral Joint
Hip FlexionHip Joint (Coxofemoral)
Ankle DorsiflexionTalocrural Joint

Why This Exercise Matters

Everyday activities this exercise helps you do — essential means it directly trains the capacity the task needs:

Pushing Up from ChairessentialSquat to StandessentialStair ClimbingessentialSingle-Leg Balance

Goals This Helps With

Rehab, performance, prevention, and mobility goals this exercise supports — essential means it's a cornerstone:

Improve Single-Leg StrengthperformanceFall PreventionpreventionKnee OsteoarthritisrehabPatellofemoral (Knee) Painrehab

Research Notes

claude-researched 2026-07 (home/bodyweight), panel-verified muscle roles + rationale. Sources not yet linked.