TRX Single-Leg Squat
The assisted pistol squat is a deep single-leg squat done while holding suspension straps, such as a TRX, so your arms can take some of your weight and steady your balance. It works the standing leg's quadriceps and glutes through a full range, with the hip muscles controlling the knee, and it is the usual stepping stone towards a free-standing pistol squat.
Also called: TRX Pistol Squat, Suspension Single-Leg Squat, Suspension-Assisted Pistol Squat, Assisted Single-Leg Squat · Equipment: suspension · Pattern: squat
Step by step
- Face the anchor point and hold both suspension handles at about chest height with your arms long and the straps taut.
- Stand on one leg with the whole foot flat and lift the other leg slightly off the floor in front of you.
- Brace your trunk, then sit down and back on the standing leg, letting the knee travel forward over the middle toes.
- Lean your chest forward as you descend to stay balanced over the foot, keeping the heel down and the free leg off the floor.
- Sink as deep as you can with control, ideally until the back of the thigh meets the calf.
- Drive through the whole foot to stand back up, using the straps only as much as you need.
- Finish tall on the standing leg, then repeat. Complete all reps on one side before switching legs.
- Hands for balance, not for pulling
- Reach the chest forward as you sit
- Heel flat on the floor
- Knee over the middle toes
- Sit to the floor, stand up tall
In VALDA, these cues are one tap away on the exercise while you train.
What it trains
| Muscle | Role | Evidence |
|---|---|---|
| Quadriceps: vastus lateralis | Prime mover | B |
| Quadriceps: vastus medialis | Prime mover | B |
| Quadriceps: vastus intermedius | Prime mover | C |
| Gluteus maximus | Prime mover | B |
| Quadriceps: rectus femoris | Secondary | C |
| Adductors | Secondary | C |
| Gluteus medius/minimus | Stabiliser | C |
| Hamstrings: biceps femoris (long head) | Stabiliser | C |
| Erector spinae | Stabiliser | C |
| Tibialis anterior | Stabiliser | C |
| Soleus | Stabiliser | C |
Evidence grades: A = strong research base · B = good · C = limited · D = coaching consensus.
What goes wrong, and the fix
Rowing yourself up with the straps
Fix: Loosen your grip and use the straps only for balance at the hardest point.
Knee caving inward at the bottom
Fix: Keep the knee tracking over the middle toes, and sink only as deep as it stays there.
Heel lifting off the floor
Fix: Keep the heel flat and sink only as deep as it stays down, or stand on a small heel lift.
Torso staying too upright
Fix: Lean your chest forward as you sit to balance the free leg in front of you.
Cutting depth short
Fix: Lean a little more on the straps to reach a full bottom rather than a shallow rep.
Dropping into the bottom
Fix: Sit down slowly and own the bottom before driving up.
What the research says
Rehab & prehab · first choiceMuscle growthGeneral fitnessSport performanceEndurance
- Single-leg transfer — A meta-analysis of 14 training studies found single-leg training carried over more to single-leg jumping, and two-leg training more to two-leg strength. Neither showed a clear edge for sprinting or change of direction.
- Range of motion — A meta-analysis found full-range training built more leg muscle and strength than partial-range training, and a 10-week squat study found full-depth squats grew the glutes and inner thighs more than half squats.
- Progressing the assistance — A common approach is to use less help from the straps over time until a free-standing pistol squat is possible. There is no direct research comparing assistance levels.
- Load and effort — Research comparing loads finds muscle growth is similar across a wide range of loads when sets are taken close to failure. Studies show sets that finish a few reps short of failure capture most of the growth benefit.
- Frequency — Training a muscle about twice a week has been associated with more growth than once a week. Many lifters practise assisted pistols two or three times a week as skill work.
Swap it mid-workout
With VALDA Pro, FLEX offers alternatives like these when you swap an exercise mid-workout.
Log the trx single-leg squat in VALDA, with these cues one tap away while you train and your history for it in one place.
General information about exercise technique, not medical advice. If you have an injury or a health condition, your healthcare provider is the right person to ask.