Ardha Chandrasana
hold 20 s each side · intermediate · move in slowly, hold, come out the same way
Take care: Practise with the back against a wall if balance is unsteady; skip it with dizziness.
Ardha Chandrasana, with a block. From a triangle-like start (front right foot turned out 90°), the weight moves onto the right leg, the right hand comes onto a block about a foot in front of the little-toe side, and the straight left leg lifts to hip height behind; the hips and chest stack open toward the side and the left arm reaches straight up. 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.
Hold for 20 seconds on each side: move into the pose slowly, breathe steadily, and come out the way you went in. Yoga 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: 39 legs points, 6 push points, 22 core points.
Gluteus medius and minimus of both legs, gluteus maximus, obliques, foot and ankle stabilisers, adductors (stretched), deltoids (holding the arm).
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.