4 reps each side · beginner
Take care: Sit on a folded blanket if the lower back rounds, keep the twist small with a back injury, and skip it after recent back surgery.
Sitting tall with the legs straight and wider than the hips and the arms out to the sides, the trunk turns about 45° to the right, then folds forward over the right leg as the left hand reaches past the outside of the right foot ("sawing off the little toe") and the right arm reaches back. Then the body rises and turns back to centre.
Bodyweight: no weights. Joint demand below is your own body's weight in this position.
Faults grow with knee bend and apply to lifts standing on the floor. The fault check flags a knee caving more than 10° inside the line of the toes and a load split beyond 60/40. Knee cave shows best in the front camera.
Femur changes keep standing height fixed by shortening or lengthening the torso. Longer femurs force more forward lean in any squat.
4 slow, controlled reps on each side. Pilates is practised for control, balance and mobility, never to failure, so this does not change with your limits.
Level: beginner. One round counts like light conditioning work: 16 legs points, 4 push points, 64 core points.
Obliques, spinal erectors, transversus abdominis; hamstrings, spinal erectors and the back of the shoulder stretched.
One 3D skeleton drives both views. Segment lengths and widths are Winter's anthropometric ratios of height; segment masses and centre-of-mass positions follow Dempster's data. For free-standing lifts the whole-body angle is found numerically so the combined centre of mass of lifter and load sits over the middle of the foot. Arms and legs use two-link inverse kinematics with a pole direction. Rep timing follows a minimum-jerk profile.
Balance is quasi-static, so ballistic lifts are shown slowed down. Cable pull and pad support forces are not modelled. The spine is one rigid segment and joints have no range-of-motion limits or muscle forces.