Significance The combinational muscle-like properties including high fatigue resistance, high strength, superior compliance, and high water content are highly desirable for various applications of soft biomaterials such as hydrogels. These combinational properties, largely attributed to the aligned nanofibrils in natural muscles, have not been achieved in synthetic hydrogels. Here, we propose a strategy of mechanical training to impart hydrogels with an extremely high fatigue threshold (1,250 J/m ² ) and strength (5.2 MPa), while maintaining a high water content (84 wt %) and a low Young’s modulus (200 kPa), reaching combinational muscle-like properties with aligned nanofibrillar architectures. We further achieve isotropically enhanced properties by three-dimensionally printing the hydrogels into microstructures.