Background/aim: Volume and T2 relaxation time measurements of the skeletal muscle provide quantitative information. We aimed to evaluate the interobserver reliability and the intraobserver reproducibility of measurements of volumes and T2 relaxation times of the quadriceps femoris and the hamstring muscles. Materials and methods: A cross-sectional reliability study was conducted on ten recreational athletes. The images of the quadriceps and the hamstring muscles of both limbs were obtained using a 3.0 Tesla magnetic resonance imaging (MRI) scanner. Two sports medicine specialists measured muscle volumes from a total of 2560 images and T2 relaxation times from a total of 40 images, and repeated this once more. The intraobserver and interobserver compliance were assessed by the intraclass correlation coefficient (ICC) and Cronbach's alpha (alpha). Results: Volume and T2 relaxation time of quadriceps femoris and hamstring muscle measurements with MRI had good to excellent reliability (Muscle volume; intraobserver ICCs: between 0.97 and 0.99, alpha: between 0.98 and 0.99 and interobserver ICCs: between 0.96 and 0.99, alpha: 0.99. T2 relaxation time; intraobserver ICCs: between 0.74 and 0.96, alpha: between 0.85 and 0.98 and interobserver ICCs: between 0.75 and 0.90, alpha: between 0.85 and 0.95). Conclusion: Volume and T2 relaxation time measurements of the quadriceps femoris and the hamstring muscles are reliable and reproducible.