Press, concentricBalanced over midfoot
Side view
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Single-arm dumbbell press

Standing, 20 kg dumbbell pressed overhead with the right arm only. The hips shift away from the weight to keep the load split even.

2°Ankle dorsiflexion
2°Knee flexion
9°Hip flexion
3°Trunk from vertical
57°Arm to trunk
154°Elbow flexion
32Ankle spacing, cm
55Hand spacing, cm
-7Knee outside ankle, cm
–Knee cave, ° inside toe line
50 / 50Load left / right, %
-1Pelvis drop, cm

Load and joint demand

Load in the model: 20 kg. Balance and joint demand re-solve as you change it.

Lower back
35 / 35
Hip extensors
19 / 19
Knee flexors
24 / 24
Calves
36 / 36
Shoulder, per side
28 / 28
Elbow, per side
38 / 54

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
100 pts
Triceps
82 pts
Lower back
32 pts
Abs and core
32 pts

Effort and your quota

3.5/10 effort3.7fatigue per set

Your quota per set: 10 reps at 20 kg, stopping 2 reps short of failure.

One hard set earns 182 push points, 82 arms points, 64 core points.

Prime movers

Deltoids, triceps, obliques and quadratus lumborum (anti-lateral lean).

What to look for

  • Stay tall; do not lean away from the dumbbell.
  • Watch the pelvis shift in the front view.
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.