10 reps each side · intermediate
Take care: Stand beside a wall or chair if your balance is unsteady.
Standing tall on the left leg, arms out to the sides, a pilates ring between the lower legs with its pads on the inside of the shins, the right leg out to the side about 30° holding it there. The right leg presses in, squeezing the ring a few centimetres, and releases slowly. The centre of mass is solved over the standing foot.
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.
10 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: intermediate. One round counts like light conditioning work: 64 legs points, 16 core points.
Adductors of the moving leg, gluteus medius and minimus of the standing leg, foot and ankle stabilisers, transversus abdominis, pelvic floor.
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.