A force sensitive resistor

A sole (100) or inner sole for a shoe is provided. The sole (100) or inner sole comprises: a toe region (28) for supporting a user's toes; a forefoot region (26) for supporting a user's forefoot; a midfoot region (24) for supporting a user's arch; and a heel region (22) for supporting a user's heel. A longitudinal direction (X) extends from the heel region (22) towards the toe region (28). A lateral direction (Y) transverse to the longitudinal direction (X) extends from an inner side to an outer side of the sole (100) or inner sole. A plurality of force sensors (10) distributed throughout the sole (100) or inner sole. The plurality of force sensors (10) comprise: a first lateral row of force sensors (10) in the toe region (28); a second lateral row of force sensors (10) in the forefoot region (26); a first longitudinal row of force sensors (10) along the inner side of the sole (100) or inner sole from the heel region (22) to the midfoot region (24); and a second longitudinal row of force sensors (10) along the outer side of the sole (100) or inner sole from the heel region (22) to the midfoot region (24).