Down, then up a quarterBalanced over midfoot, bar 0.1 cm behind
Side view
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One-and-a-quarter squat

Back squat with 90 kg: down to the bottom, up a quarter of the way, back down to the bottom, then all the way up. Each rep spends twice as long in the hardest position.

2°Ankle dorsiflexion
2°Knee flexion
9°Hip flexion
6°Trunk from vertical
35°Arm to trunk
138°Elbow flexion
42Ankle spacing, cm
84Hand spacing, cm
-6Knee outside ankle, cm
–Knee cave, ° inside toe line
50 / 50Load left / right, %
0Pelvis drop, cm

Load and joint demand

Load in the model: 90 kg. Balance and joint demand re-solve as you change it.

Lower back
11 / 374
Hip extensors
10 / 222
Knee extensors
28 / 106
Calves
58 / 58

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
Adductors
64 pts
Lower back
46 pts

Effort and your quota

9/10 effort9.4fatigue per set

Your quota per set: 10 reps at 90 kg, stopping 2 reps short of failure.

One hard set earns 246 legs points, 46 core points.

Prime movers

Quadriceps, gluteus maximus, adductors, spinal erectors.

What to look for

  • Come up only a quarter, about a hand's height.
  • Sink back to full depth before you stand.
  • Use about 20% less weight than your normal squat.
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.