The hundred is a Pilatesabsexercise performed lying on your back with the head and shoulders curled off the mat and the legs raised, pumping the arms through one hundred breath counts to train the deep core under a held curl. Nothing about the trunk moves once you are in position: the rectus abdominis and transverse abdominis hold a fixed upper-body curl while the arm pumps and the paced breathing try to shake it loose, so the exercise trains endurance rather than range. Pilates sessions open with it, and lifters can use it the same way before core work.
What Muscles Does the Hundred Work?
- Primary: Rectus abdominis, transverse abdominis (deep core)
- Secondary: Iliopsoas (hip flexors), obliques
- Tertiary: Neck flexors, serratus anterior, quadriceps
How Do You Set Up for the Hundred?
Lie on your back on a mat with your arms long by your sides, palms down, and your spine neutral. Draw your knees up one at a time until the shins are parallel to the floor and the knees sit over the hips, in tabletop. Curl your head, neck and shoulder blades off the mat, eyes toward your knees, and hover both arms a few inches above the floor at hip height.
How Do You Perform the Hundred?
- Hold the curl with your shoulder blades just off the mat and your gaze fixed on your knees, arms hovering long at hip height.
- Extend both legs to a forty-five degree angle from the floor, or keep tabletop if your lower back begins to lift.
- Pump the arms up and down through a range of about six inches, moving from the shoulders with the elbows straight.
- Inhale through your nose for five pumps, keeping the ribs knitted down and the belly flat.
- Exhale through your mouth for five pumps, pressing the lower back into the mat and deepening the curl slightly.
- Repeat the ten-count cycle ten times for one hundred pumps, then bend the knees, lower the head, and rest the arms.
What Are the Key Form Cues?
- Reach the fingertips toward the far wall: length through the arms keeps the shoulders down and stops the pump becoming a shrug.
- Curl from the sternum, not the chin: the lift comes from folding the ribcage toward the pelvis, with the neck following.
- Keep the pump small and quick, with the breath, so the trunk is never rocked by an arm swing.
- Imagine your lower back is glued to the mat, especially on each exhale.
- Let your eyes stay on your knees; when they drift to the ceiling, the curl has dropped.
What Are the Most Common Mistakes?
- Holding the legs too low: a leg angle you cannot own pulls the lower back into an arch and loads the lumbar spine; return to tabletop until the back stays flat.
- Pulling with the neck: the chin jams to the chest and the throat tires before the abs; lift from the ribs and keep a fist of space under the chin.
- Pumping from the elbows: bending the arms turns the pump into a flap and takes the shoulder stabilisers out; keep the arms straight and move from the shoulder.
- Holding the breath: the ribs lock, the abs cannot deepen the curl, and the count falls apart; keep the five in, five out rhythm audible.
- Letting the shoulders lift to the ears: a shrug shifts tension to the upper traps; slide the shoulder blades down as the head lifts.
What Are the Best Hundred Variations?
- Hundred with feet down: heels on the mat, removing the leg hold for beginners learning the curl and breath.
- Straight-leg hundred: legs held together just above the mat, a much longer lever for strong lower abs.
- Hundred with ball squeeze: a small ball between the knees, adding an adductor squeeze that pins the pelvis.
- Single-leg hundred: one leg extended, the other in tabletop, switching halfway, to expose hip flexor differences.
- Hundred on a bench: lying on a flat bench with legs off the end, giving room for the arm pump.
How Do You Progress the Hundred?
- Lower the leg angle from tabletop toward forty-five degrees, then toward the mat, as long as the back stays down.
- Build the count in blocks of twenty pumps per session until you reach the full hundred.
- Add a second set of one hundred once the first stays clean from start to finish.
- Slow the breath to a six-count in and six-count out while keeping the pump tempo the same.
How Should You Program the Hundred?
Use the hundred as the opener of a core session or Pilates practice, before any loaded trunk work, since it warms up the breath and the curl together. Do it 2 to 4 times per week for 1 to 2 sets of one hundred pumps, resting 60 seconds between sets if you run two. Follow it with roll-ups or leg circles that use the same held curl.