Part of these sets

This exercise rarely works alone. It appears in the following routines, where it is sequenced alongside the others that support it.

What it works

Primary muscles

Transversus abdominis and obliques
Rectus abdominis, working as a brake

Also involved

Hip flexors, controlling the lowering leg
Pelvic floor, coordinating with each exhale

Equipment: None. A mat or folded blanket.

How to do it

1
Lie on your back. Lift the knees so hips and knees are at right angles, shins parallel to the floor: the tabletop position. Reach both arms straight up above the shoulders. The lower back rests lightly against the floor.
2
Breathe in, then as you breathe out gently draw the lower abdomen inward, roughly a three out of ten effort, so the midline stays firm rather than doming. A quiet connection, not sucking in.
3
On that exhale, slowly lower one arm overhead and the opposite leg towards the floor, only as far as the lower back keeps its light contact.
4
Breathe in as you bring both back to the start, then repeat with the other pair.
5
Keep every repetition slow, and watch the midline: a ridge rising down the centre means shorten the range.

How much to do

2 to 3 sets of 6 to 8 slow repetitions each side

3 to 4 times a week

Progress by lengthening the lever and slowing the tempo, never by speeding up. Rebuilding midline control takes weeks of consistent work, not days.

Stop and get assessed if

Stop and get assessed if you cannot find any range without doming along the midline, if you feel pelvic heaviness or leaking during or afterwards, or if repetitions provoke back pain rather than abdominal effort. Doming and heaviness are signals to regress and have the load checked, not faults to push through.

Common mistakes

The lower back arching off the floor as the leg lowers: Wherever contact is lost is where your range currently ends. Shorten the movement; an arched repetition loads the back instead of the abdominals, and range grows as control does.
Doming along the midline: A ridge down the centre of the abdomen means the load is currently above what your midline can control. Shorten the lever or drop to a regression: reduce it, do not abandon it.
Holding the breath and bracing hard: The gentle draw on the exhale is the mechanism. A rigid breath-hold spikes pressure, which is exactly what pushes a midline into doming and bears down on the pelvic floor.
Moving quickly: Speed hands the work to momentum. If you can do it fast, the lever is too short to be training anything; slow it down before you lengthen it.

Making it harder

Lower the arm and leg further, hovering just above the floor without resting down.
Straighten the moving leg fully as it lowers, which lengthens the lever considerably.
Slow the tempo to four counts out and four counts back.
Add small weights in the hands once everything else is boringly controlled.

Making it easier

Heel taps: keep the knees bent, arms resting by your sides, and tap one heel lightly to the floor at a time.
Arms only: keep both legs still in tabletop and lower one arm at a time overhead.

Dead Bug