phosphorylation of bcrystallin and its cytoskeleton association differs in skeletal myofiber types depending on resistance exercise intensity and volume bcrystallin cryab is an important actor in the immediate cell stabilizing response following mechanical stress in skeletal muscle yet only little is known regarding myofiber typespecific stress responses of cryab we investigated whether the phosphorylation of cryab at serine 59 pcryabser59 and its cytoskeleton association are influenced by varying loadintensity and volume in a fiber typespecific manner male subjects were assigned to 1 5 and 10 sets of different acute resistance exercise protocols hypertrophy hyp maximum strength max strength endurance se low intensity li and three sets of maximum eccentric resistance exercise ecc skeletal muscle biopsies were taken at baseline and 30 min after exercise western blot revealed an increase in pcryabser59 only following 5 and 10 sets in groups hyp max se and li as well as following 3 sets in the ecc group in type i fibers immunohistochemistry determined increased pcryabser59 in all groups in type ii fibers pcryabser59 only increased in max and ecc groups with the increase in type ii fibers exceeding that of type i fibers in ecc association of cryab and pcryabser59 with the cytoskeleton reflected the fiber typespecific phosphorylation pattern phosphorylation of cryab and its association with the cytoskeleton in type i and ii myofibers is highly specific in terms of loading intensity and volume most likely this is based on specific recruitment patterns of the different myofiber entities due to the different resistance exercise loadings we conclude that pcryabser59 indicates contractioninduced mechanical stress exposure of single myofibers in consequence of resistance exercise new noteworthy we determined that the phosphorylation of bcrystallin at serine 59 pcryabser59 after resistance exercise differs between myofiber types in a load and intensitydependent manner the determination of pcryabser59 could serve as a marker indirectly indicating contractile involvement and applied mechanical stress on individual fibers by that it is possible to retrospectively assess the impact of resistance exercise loading on skeletal muscle fiber entities