The combination of myostatin inhibition and SMN upregulation holds promise as a therapeutic strategy in SMA by offering a two-pronged approach that targets the whole motor unit via mechanisms of action that include: (1) optimizing SMN protein and directly restoring motor neuron function with SMN upregulators and (2) reversing muscle atrophy by inhibiting the myostatin and activin A pathway. Here, MSTN is linked to proximal spinal muscular atrophy.