Syncoilin is a 64-kDa intermediate filamentprotein expressed in skeletal muscle and enriched atthe perinucleus, sarcolemma, and myotendinous andneuromuscular junctions. Due to its pattern of cellularlocalization and binding partners, syncoilin is an idealcandidate to be both an important structural component ofmyocytes and a potential mediator of inherited myopathies.Here we present a report of a knockout mouse model forsyncoilin and the results of an investigation into the effectof a syncoilin null state on striated muscle function in 6–8-week-old mice. An analysis of proteins known to associatewith syncoilin showed that ablation of syncoilin had noeffect on absolute expression or spatial localization ofdesmin or alpha dystrobrevin. Our syncoilin-null animalexhibited no differences in cardiotoxin-induced muscleregeneration, voluntary wheel running, or enforced treadmillexercise capacity, relative to wild-type controls.Finally, a mechanical investigation of isolated soleus andextensor digitorum longus indicated a potential differentialreduction in muscle strength and resilience. We are the firstto present data identifying an increased susceptibility tomuscle damage in response to an extended forced exerciseregime in syncoilin-deficient muscle. This study establishesa second viable syncoilin knockout model and highlightsthe importance of further investigations to determine therole of syncoilin in skeletal muscle.