Eka Pada Adho Mukha Svanasana
hold 20 s each side · beginner · move in slowly, hold, come out the same way
Take care: Rest the knee down or stay in downward dog if the wrists hurt; skip long holds with high blood pressure or glaucoma, as the head is below the heart.
Eka Pada Adho Mukha Svanasana, the square-hips version most classes teach first: from downward-facing dog (hands shoulder-width, feet hip-width, hips high), the right leg lifts straight back and up until it is in line with the trunk, the hips kept level and the toes of the lifted foot pointing down. The left heel keeps reaching toward the mat; the arms and trunk stay where they were.
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: beginner. One round counts like light conditioning work: 72 legs points, 51 push points, 22 arms points, 12 core points.
Gluteus maximus and hamstrings of the lifted leg, deltoids, triceps, serratus anterior, hamstrings and calf of the standing leg (stretched), spinal erectors.
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.