The single leg stretch is the first exercise in the classical Pilates abdominal series, often called the series of five. To do it, lie on your back and curl your head and shoulders off the mat, then draw one knee toward your chest while extending the other leg long at an angle. Place your outside hand on the ankle and your inside hand on the knee of the bent leg. Switch legs in a steady rhythm, drawing the other knee in as the first leg extends, and keep your upper body lifted and your pelvis still. A common breath pattern is to inhale for two switches and exhale for two. Eight to ten switches per side is typical. Keep the extended leg higher if your lower back arches, and rest your head down if your neck tires. It builds abdominal endurance, coordination and core stability.
Health note: This article is general information, not medical advice. Check with a doctor or physical therapist before starting Pilates if you have back, neck, hip or knee problems, osteoporosis, are pregnant or postpartum, or are recovering from injury. The lifted head and shoulders place the spine in flexion, which some people are advised to modify. Ideally, learn exercises from a qualified instructor.
What the single leg stretch trains
The single leg stretch challenges the abdominals to hold the upper body in a curl while the legs move underneath. The deep abdominals stabilize the pelvis and lower back against the pull of the extended leg, the obliques help keep the trunk steady as the legs switch, and the upper abdominals hold the head and shoulders lifted. The hip flexors work to hold the extended leg in the air, and the hand placement encourages the bent knee to track straight toward the shoulder. The result is a test of abdominal endurance and coordination, with a mild stretch for the lower back and hip of the bent leg.
Step by step
| Step | Key point |
|---|---|
| Set | Lie on your back, curl head and shoulders up, knees to chest |
| Hands | Outside hand on the ankle, inside hand on the knee of the bent leg |
| Switch | Extend one leg while pulling the other knee in |
| Breathe | Inhale for two switches, exhale for two |
| Repeat | 8 to 10 per side |
How to do the single leg stretch
- Lie on your back and draw both knees into your chest.
- Exhale and curl your head, neck and shoulders off the mat, lifting to the base of your shoulder blades.
- Draw your abdominals in, using an imprint or a stable neutral depending on your instructor’s cue.
- Extend your left leg long at an angle, around 45 degrees or higher, while keeping your right knee bent toward your chest.
- Place your right hand on your right ankle and your left hand on your right knee. This helps keep the knee aligned with the hip.
- Switch legs: draw the left knee in as you extend the right leg, and switch your hands so the outside hand is on the ankle and the inside hand on the knee.
- Continue switching in a smooth, steady rhythm, keeping the upper body lifted and still.
- Complete eight to ten switches per side, then draw both knees in and lower your head to rest.
Keeping the torso still
The legs move, but the upper body and pelvis should not. Keep your gaze toward your knees and hold the curl steady rather than bobbing up and down with each switch. The pelvis stays level and quiet, without rocking side to side. If you notice your shoulders dropping back to the mat or your hips rolling, slow the tempo. A controlled rhythm with a stable torso is worth more than fast switches with a moving body.
Leg height and the lower back
The lower the extended leg, the harder the exercise and the more it pulls on the lower back. Start with the leg higher, even pointing toward the ceiling, and lower it only as far as you can while keeping your back supported and still on the mat. If the lower back arches or lifts, raise the leg. Over time, as abdominal strength builds, you can gradually lower it.
Hand placement explained
The classical cue is outside hand to ankle, inside hand to knee. For example, when the right knee is bent, the right hand goes to the right ankle and the left hand to the right knee. This placement gently guides the knee in line with the hip and shoulder and prevents it from falling outward. It also adds a coordination challenge as the hands switch with the legs. If the hand pattern feels confusing or strains your shoulders, you can place both hands lightly on the shin or reach the arms long beside you until the leg rhythm feels natural.
Breathing and rhythm
The common pattern is to inhale for two switches and exhale for two, though some instructors use one breath per switch or a percussive exhale. The rhythm should be steady and even, like a metronome. If the breath feels rushed or you start holding it, slow down. The exercise should feel challenging but controlled, not frantic.
Modifications
- Rest your head on the mat or a small cushion if your neck tires.
- Keep the extended leg higher to protect the lower back.
- Slow the tempo to focus on control.
- Simplify the hands, placing both on the bent shin or keeping the arms by your sides.
- Do fewer repetitions with good form rather than more with poor form.
- Keep the bent knee closer to 90 degrees if drawing it into the chest is uncomfortable.
Where it fits in a Pilates session
In the classical mat order, the single leg stretch follows rolling like a ball and begins the abdominal series, followed by the double leg stretch, single straight leg stretch (scissors), double straight leg stretch and criss-cross. Many instructors teach these five in sequence as one block. The single leg stretch is usually considered a beginner to intermediate exercise and is often the first part of the series that students learn.
How to progress
Start with your head down and the extended leg high, focusing on smooth switching and a still pelvis. Next, add the head and shoulder curl for short sets. Then gradually lower the extended leg and increase the repetitions. Once the single leg stretch feels steady, move on to the double leg stretch, which demands more coordination and core control.
Common mistakes to avoid
- Rocking the pelvis side to side as the legs switch.
- Dropping the upper body or bobbing with each switch.
- Lowering the leg too far and arching the lower back.
- Pulling on the knee with the hands.
- Tensing the neck and jutting the chin forward.
- Rushing the rhythm.
- Holding the breath.
Frequently asked questions
What does the single leg stretch work?
It mainly works the abdominals, especially the deep core, while also engaging the hip flexors and training coordination.
Why does my neck hurt during the single leg stretch?
Neck strain often means the abdominals are not supporting the curl or the chin is jutting forward. Rest your head down, lengthen the neck and build strength gradually.
What is the Pilates series of five?
It is a sequence of five abdominal exercises: single leg stretch, double leg stretch, single straight leg stretch, double straight leg stretch and criss-cross.
