Pedal
Side view
Drag to orbit, pinch or scroll to zoom

Air bike

On an air (fan) bike: the legs pedal while the arms push and pull the moving handles, right arm pushing as the right leg pushes. The bike is drawn as scenery: seat, frame and fan.

54°Ankle dorsiflexion
111°Knee flexion
71°Hip flexion
14°Trunk from vertical
39°Arm to trunk
125°Elbow flexion
24Ankle spacing, cm
48Hand spacing, cm
4Knee 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.

No gravity-based joint demand to show for this exercise.

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
Hamstrings
64 pts
Chest
46 pts
Upper back
35 pts
Shoulders
35 pts

Effort and your quota

9/10 effort9fatigue per set

Your quota per set: 45 s hard, stopping 2 reps short of failure.

One hard set earns 246 legs points, 81 push points, 35 pull points.

Prime movers

Quadriceps, gluteus maximus, hamstrings, chest, upper back, deltoids.

What to look for

  • Push and pull with the arms as hard as the legs drive.
  • Seat high enough that the knee is only slightly bent at the bottom.
  • Sit tall; don't rock side to side.
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.