Dip and jump
Side view
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Box jump

A counter-movement jump from the floor onto a 50 cm box, landing softly in a quarter squat with both feet fully on the box, then standing tall. The demonstration steps back down by reversing the jump.

3°Ankle dorsiflexion
2°Knee flexion
4°Hip flexion
3°Trunk from vertical
13°Arm to trunk
15°Elbow flexion
28Ankle spacing, cm
56Hand spacing, cm
-3Knee outside ankle, cm
–Knee cave, ° inside toe line
–Load left / right, %
0Pelvis drop, cm

Load and joint demand

Bodyweight exercise: the load slider has no effect here; body mass comes from your limits.

Shoulder, per side
3 / 12

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

Quads
100 pts
Glutes
82 pts
Calves and shins
64 pts
Hamstrings
46 pts

Effort and your quota

7.5/10 effort7.5fatigue per set

Your quota per set: 6 reps at bodyweight, stopping 2 reps short of failure.

One hard set earns 273 legs points.

Prime movers

Quadriceps, gluteus maximus, calves, hamstrings.

What to look for

  • Swing the arms back on the dip and up on the jump.
  • Land quietly with the whole foot on the box, knees over the toes.
  • Stand up fully on the box, then step down; don't jump down.
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.