Understanding Gluteus Maximus Tension Lines: Anatomy Meets Function The gluteus maximus, the largest muscle in the body, plays an important role in hip stability, movement, and power. Its tension lines reflect the arrangement of its fibres, which dictate its function and interaction with the kinetic chain. Key Points About Tension Lines • Fibre Orientation: The fibres run diagonally from the iliac crest, sacrum, and coccyx (origin) to the iliotibial band (ITB) and gluteal tuberosity of the femur