Rolls and step-overs on the spot
6 reps · intermediate
The right sole rolls the ball across to the left; the left foot steps over it from the inside to the outside, round the front of the ball without touching it, and lands beyond it; the left sole rolls it back to the middle. Then the same starting with the left. A roll and a step-over on the spot.
A size 5 football and your own bodyweight: no weights.
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.
6 reps (a rep is the whole move as shown): light touches, the ball kept close. Ball mastery is practised for touch, balance and coordination, never to failure, so this does not change with your limits.
Level: intermediate. One round counts like light conditioning work: 95 legs points, 12 core points.
Adductors, gluteus medius, calves, quadriceps, obliques.
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.