OpenBalanced over midfoot
Side view
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Dumb waiter

10 reps · beginner

Standing tall with the feet hip-width apart, the elbows bent to 90° and tucked into the waist, the forearms pointing forward with the palms up, as if carrying a tray. The forearms open out to the sides, the shoulder blades drawing gently together, while the elbows stay at the waist; then they return.

6°Ankle dorsiflexion
3°Knee flexion
3°Hip flexion
0°Trunk from vertical
6°Arm to trunk
90°Elbow flexion
20Ankle spacing, cm
45Hand spacing, cm
-1Knee outside ankle, cm
–Knee cave, ° inside toe line
50 / 50Load left / right, %
0Pelvis drop, cm

Load and joint demand

Bodyweight: no weights. Joint demand below is your own body's weight in this position.

Knee flexors
11 / 11
Calves
29 / 29

N·m now / peak over the rep.

Faults

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.

Body

Femur changes keep standing height fixed by shortening or lengthening the torso. Longer femurs force more forward lean in any squat.

Muscles worked

Upper back
29 pts
Abs and core
16 pts

Effort and your quota

2.5/10 effort2.5fatigue per set

10 slow, controlled reps. 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: 29 pull points, 16 core points.

Prime movers

Infraspinatus and teres minor (rotating the arms out), rhomboids and middle trapezius, posterior deltoid, transversus abdominis.

What to look for

  • Keep the elbows glued to the waist; only the forearms swing.
  • Open only as far as the ribs stay down and the shoulders stay low.
  • Breathe out as the arms open.
How the model works, and its limits

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.