In Pilates, the core, often called the powerhouse, is much more than the six-pack. It is a group of deep and superficial muscles that wrap around the trunk and pelvis. The deep stabilizers are the transversus abdominis, multifidus, pelvic floor and diaphragm, which together support the spine and pelvis. The superficial movers are the rectus abdominis and the obliques, which bend and rotate the trunk. The back extensors, glutes and hip muscles are often counted as part of the powerhouse too. Pilates trains all of these to work together, first by learning to engage the deep layer with breathing and a gentle abdominal scoop, then by holding that support while the arms and legs move. A well-trained core helps provide a stable base for posture, daily movement and sport.
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 or joint problems, pelvic floor symptoms, diastasis recti, are pregnant or postpartum, or are recovering from injury. Ideally, learn exercises from a qualified instructor.
What the powerhouse means
Joseph Pilates used the word powerhouse to describe the center of the body from which movement should originate. Instructors define it slightly differently, but it generally includes the abdominals, the muscles of the lower back, the pelvic floor, the glutes and the inner thighs. The idea is that a strong, coordinated center allows the limbs to move freely and efficiently. Modern anatomy supports parts of this view: the deep trunk muscles help control pressure inside the abdomen and stiffen the spine in anticipation of movement, which can help transfer force between the upper and lower body.
The core muscles at a glance
| Muscle | Role | Pilates examples |
|---|---|---|
| Transversus abdominis | Deep corset that stabilizes the spine | Scooping, the hundred |
| Rectus abdominis | Flexes the spine | Roll up, single leg stretch |
| Internal and external obliques | Rotation and side bending | Crisscross, saw, side bends |
| Multifidus | Deep spinal stabilizer | Swan, swimming |
| Erector spinae | Extends and supports the spine | Swan, double leg kick |
| Pelvic floor | Supports pelvic organs, stabilizes pelvis | Pelvic floor engagement |
| Diaphragm | Breathing muscle forming the top of the core | Lateral breathing |
| Glutes and hip muscles | Stabilize and move the pelvis and hips | Pelvic curl, side kicks |
The deep stabilizers
Transversus abdominis: The deepest abdominal muscle wraps horizontally around the trunk like a corset. When it contracts, it draws the belly in and helps increase support around the spine. In Pilates, it is the main target of the abdominal scoop and imprint.
Multifidus: These small muscles run along the spine, connecting individual vertebrae. They help control segmental movement and stability. They tend to work with the transversus abdominis and are trained in exercises that require a steady, long spine.
Pelvic floor: This sling of muscles at the base of the pelvis supports the bladder, bowel and pelvic organs and forms the floor of the core. It often activates together with the deep abdominals.
Diaphragm: The main breathing muscle forms the roof of the core. Its coordination with the pelvic floor and deep abdominals helps manage pressure inside the trunk. Lateral breathing in Pilates encourages this teamwork.
The superficial movers
Rectus abdominis: The six-pack muscle runs vertically down the front of the abdomen and flexes the spine, as in the roll up or curling the head and shoulders off the mat.
Obliques: The internal and external obliques run diagonally along the sides of the trunk. They rotate and side bend the spine, and they help resist unwanted rotation. Exercises like the crisscross, saw and side plank target them.
Erector spinae: These long muscles along the back extend the spine and help hold it upright. Prone exercises like the swan, swimming and double leg kick strengthen them.
The glutes, hips and inner thighs
Although they are not abdominal muscles, the glutes, deep hip rotators and inner thighs play a big role in the Pilates powerhouse. The glutes extend and stabilize the hip and help keep the pelvis level during single-leg work. The deep hip rotators fine-tune the position of the thigh in the socket, and the inner thighs connect to the pelvis and are thought to work alongside the pelvic floor. Pilates stance, bridging, side kicks and leg circles all train these muscles. Including them in core training matters because the pelvis is the link between the trunk and the legs, and a stable pelvis supports almost every movement you make.
Signs of good core control
You do not need a visible six-pack to have a strong, well-coordinated core. More useful signs are the ability to keep the pelvis still while moving an arm or leg, to breathe steadily during effort, to roll the spine smoothly without jerking, and to hold a plank or side plank without the hips sagging. In daily life, good core control often shows up as easier lifting, steadier balance and more comfortable posture during long periods of sitting or standing.
How the core works together
The core muscles rarely work alone. A useful model is to think of a cylinder: the diaphragm at the top, the pelvic floor at the bottom, the transversus abdominis around the front and sides, and the multifidus at the back. When these coordinate, they help create a stable base. The superficial muscles then produce larger movements such as bending, twisting and extending. Pilates starts by teaching the deep layer, then gradually adds limb movement and larger trunk movements while keeping the deep support in place. This progression, from stability to controlled movement, is one of the defining features of the method.
How to train the core in Pilates
- Learn lateral breathing to coordinate the diaphragm with the deep abdominals.
- Practice the abdominal scoop and pelvic floor lift while lying still.
- Find neutral spine and imprint, the two main starting positions.
- Add small limb movements such as heel slides and toe taps while keeping the core steady.
- Progress to classical exercises like the hundred, roll up and single leg stretch.
- Include back and side work, such as the swan, swimming and side kicks.
- Add rotation and advanced challenges like the crisscross, saw and teaser as control improves.
Why a strong core matters
A well-coordinated core helps support posture, protect the spine during daily tasks such as lifting and carrying, and transfer force efficiently in sport. It can also improve balance and body awareness. Research on core training and back pain is mixed, and there is no single ideal way to train the core, but many people find that Pilates-based core work helps them move with more confidence and control. For best results, core training should be part of a broader program that includes general strength, mobility and cardiovascular exercise.
Common mistakes to avoid
- Focusing only on the six-pack and ignoring deep and back muscles.
- Bracing too hard and holding the breath.
- Doing endless crunches instead of varied, controlled movements.
- Neglecting the back extensors and glutes.
- Skipping the fundamentals and jumping to advanced exercises.
- Ignoring pelvic floor symptoms that need professional assessment.
Frequently asked questions
What is the powerhouse in Pilates?
It is the Pilates term for the center of the body, generally including the abdominals, lower back, pelvic floor, glutes and inner thighs.
Which core muscle does Pilates target most?
Pilates places particular emphasis on the transversus abdominis, the deep corset muscle, while also training the rest of the core.
Is Pilates good for core strength?
Many people find it effective for building core control and endurance, especially when combined with other forms of strength training.
