What is a sensible starting dose for the underswitch and what should I master first?

Start with 2 sets of 3 to 5 slow reps per side, resetting to a full beast hold between reps rather than chaining them. You should already own a controlled side kickthrough with the hips lifting clean and no low-back strain before adding the overhead reach and full rotation of the underswitch.

How do I make the underswitch easier or harder?

To make it easier, drop the overhead arm reach and just thread the leg through while keeping both hands down, building the rotation without the balance challenge. To make it harder, slow the whole rep to a five-second count each way, or add a full outside pivot before threading back to beast.

What is the underswitch good for and when should I skip it?

It builds rotary core power, thoracic mobility, and single-arm shoulder stability for athletes and flow practitioners chasing full-body control rather than raw strength. Skip it if you have wrist pain when weight-bearing or a shoulder that is not yet stable overhead, since the move briefly loads one arm through an open, rotated position.

Advanced

Underswitch

The underswitch is where crawling becomes true flow. From the beast, you lift a hand, drive the opposite leg through under your torso, and rotate your hips open toward the ceiling before reversing the path. It builds rotary power, thoracic mobility, and single-arm shoulder stability all at once. Earn the side kickthrough first, because this move demands you own the open rotation under control.

Equipment: Body Weight
Body part: Abs, Shoulder
Type: Balance, Functional
Browse by muscle: Abdominal External Oblique, Deltoid Anterior, Gluteus Maximus
Browse by movement: Rotation

How to do it

1
Start in a beast hold with knees hovering and a braced core.
2
Lift the right hand and kick the left leg through under the body toward the right side.
3
Rotate the hips open so the chest turns toward the ceiling, planting the left foot and reaching the right arm overhead.
4
Pause in the open position with the hips lifted and the supporting arm stacked under the shoulder.
5
Reverse the path precisely, threading the leg back under to return to the beast.
6
Alternate sides for the prescribed reps, moving slowly and deliberately.

Tips

Lead with the eyes and chest as you open; letting the head lag flattens the rotation.
Keep the traveling foot low to the floor so the leg threads cleanly instead of swinging wide.
Squeeze the glute of the down leg at the top to drive the hips high and protect the low back.

Variations

Common mistakes

Once the rotation opens, the hips sink instead of lifting, dropping the reach into a low twist instead of a stacked underswitch.
The supporting wrist collapses inward as the arm goes overhead, rolling the load onto the outside edge of the hand.
The traveling knee drops toward the floor mid-thread, turning the switch into a crawl-and-drag instead of a clean pass-through.
Rushing the return trip back to beast lets the hips crash down instead of reversing the same controlled arc.
The neck strains to look at the planted foot instead of following the chest's rotation, which stalls the turn halfway.

Frequently asked

What is a sensible starting dose for the underswitch and what should I master first?: Start with 2 sets of 3 to 5 slow reps per side, resetting to a full beast hold between reps rather than chaining them. You should already own a controlled side kickthrough with the hips lifting clean and no low-back strain before adding the overhead reach and full rotation of the underswitch.
How do I make the underswitch easier or harder?: To make it easier, drop the overhead arm reach and just thread the leg through while keeping both hands down, building the rotation without the balance challenge. To make it harder, slow the whole rep to a five-second count each way, or add a full outside pivot before threading back to beast.
What is the underswitch good for and when should I skip it?: It builds rotary core power, thoracic mobility, and single-arm shoulder stability for athletes and flow practitioners chasing full-body control rather than raw strength. Skip it if you have wrist pain when weight-bearing or a shoulder that is not yet stable overhead, since the move briefly loads one arm through an open, rotated position.

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