We humans walk with our feet. This is true, but not entirely. Walking, as part of locomotion, is a coordinated whole-body movement that involves both the arms and legs. Researchers at the Biozentrum of the University of Basel and the Friedrich Miescher Institute for Biomedical Research have identified different subpopulations of neurons in the spinal cord with long projections. Published in Neuron, the results show that these neurons coordinate movement of arms and legs and ensure a stable body posture during locomotion.