What the muscles do

A muscle can only pull. Shorten it to see what it moves.

Muscle
Hamstrings, from the side30°120°135°0°30°120°135°0°30°120°135°0°30°120°135°0°30°120°135°0°30°120°135°0°30°120°135°0°30°120°135°0°30°120°135°0°30°120°135°0°30°120°135°0°30°120°135°0°30°120°135°0°
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shorter (pulls) 100 % of its standing length longer (stretched)

standing On the bike: 109 to 117 % of its standing length (road bike, 178 cm)

Hamstrings Mm. ischiocrurales

Shorter: extends the hip and bends the knee, both at once.

  • Hip: as when standing
  • Knee: as when standing

Hip, usual range: 30° extended to 120° flexedKnee, usual range: 135° flexed to extended

See it in 3D with anatomy →

A model, not an atlas: the muscle shapes come from real 3D meshes, fitted to a figure with the measurements of ANSUR II; joint limits from the usual norms (AAOS), the limits of the hamstrings, the front of the thigh and the calf from Kendall's length tests.

Shapes of muscles and bones: BodyParts3D, © The Database Center for Life Science, CC BY 4.0, fitted to the figure and simplified.