RiseBalanced over midfoot
Side view
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Single-leg dumbbell calf raise

Standing on the right foot with a 16 kg dumbbell in the right hand and the left knee bent behind. The foot rotates up to 30° about the ball while whole-body lean is solved to stay over the ball of one foot.

5°Ankle dorsiflexion
2°Knee flexion
6°Hip flexion
4°Trunk from vertical
6°Arm to trunk
0°Elbow flexion
9Ankle spacing, cm
52Hand spacing, cm
4Knee outside ankle, cm
–Knee cave, ° inside toe line
–Load left / right, %
0Pelvis drop, cm

Load and joint demand

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

Lower back
21 / 29
Hip extensors
12 / 18
Knee flexors
5 / 14
Calves
73 / 117

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

Calves and shins
100 pts

Effort and your quota

1.5/10 effort1.6fatigue per set

Your quota per set: 10 reps at 16 kg, stopping 2 reps short of failure.

One hard set earns 70 legs points.

Prime movers

Gastrocnemius, soleus, foot stabilisers.

What to look for

  • Rise all the way up, then lower slowly into a full stretch.
  • Balance over the big toe; a fingertip on a wall is fine.
  • Keep the knee straight but not locked.
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.