15 Foot core strengthening: an update about the intrinsic foot muscles recruitment

Abstract

Background Dynamic foot control arises from the complex interaction between active and passive structures and this is of primary interest in rehabilitation following lower limb injuries. However, the intrinsic foot musculatures remain a largely disregarded group of muscles in rehabilitation and strengthening programmes. Objective To provide an update regarding the recruitment and the strengthening of the intrinsic foot muscles as an active component of the foot core system. Design Review of existing literature and personal experience. Setting Not applicable. Patients Not applicable. Interventions Training of the foot core (from isolation to integration) through: (1) isolated foot core training (the “short foot exercise”); (2) isolated neuromuscular electrostimulation (NMES) of the intrinsic foot muscles and (3) integration and progression through dynamic tasks. Main outcome measurements Not applicable. Results The “short foot” is an excellent exercise for isolating the plantar intrinsic foot muscles, emphasising the volitional control of these muscles. NMES is known to prevent medial arch collapse in dynamic conditions (fast running), through a lateral shift in the foot plantar pressure patterns; it also enhances rear-foot inversion and the rising of the medial longitudinal arch during gait. Integration of foot core control skills during heel raises, hopping and running activities is very important in order to promote the use of the intrinsic foot muscles during dynamic activities in which entire foot core system is integrated. Conclusions Training the intrinsic foot muscles may offer benefit to the foot core system by increasing the functional variability of degrees of freedom to cope with changing demands of dynamic foot control. Moving from targeted isolation of these muscles to their global integration in movement patterns may offer an excellent strategy for reducing the effects of lower extremity overuse injuries related to poor foot control. Further specific research into this is warranted.