StepCentre of mass inside base of support
Side view
Drag to orbit, pinch or scroll to zoom

Overhead carry

Two 16 kg dumbbells locked out overhead, shown as a march on the spot because the model has no walking gait yet.

4°Ankle dorsiflexion
2°Knee flexion
1°Hip flexion
3°Trunk from vertical
174°Arm to trunk
15°Elbow flexion
20Ankle spacing, cm
34Hand spacing, cm
-1Knee outside ankle, cm
–Knee cave, ° inside toe line
50 / 50Load left / right, %
0Pelvis drop, cm

Load and joint demand

Load in the model: 16 kg each hand. Balance and joint demand re-solve as you change it.

Lower back
25 / 25
Hip extensors
15 / 15
Knee extensors
23 / 67
Calves
40 / 80

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

Shoulders
60 pts
Triceps
49 pts
Upper back
38 pts
Abs and core
28 pts

Effort and your quota

4/10 effort4fatigue per set

Your quota per set: carry 16 kg each hand for 42 s, stopping 2 reps short of failure.

One hard set earns 109 push points, 38 pull points, 49 arms points, 28 core points.

Prime movers

Deltoids, triceps, upper trapezius, core.

What to look for

  • Biceps by the ears, ribs down.
  • If the lower back arches, the weight is too heavy.
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.