An organism’s morphology (how its body is shaped) affects its performance (how effectively it carries out tasks like sprinting and climbing). This relationship can change in different contexts. For example, we might expect to find trade-offs whereby beneficial morphology in one environment can be detrimental in another environment. Furthermore, understanding how morphology affects performance in novel environments is necessary to understand how invaders can be successful. We tested this morphology-performance relationship in a successful global colonizer, the common wall lizard (Podarcis muralis), to address three primary questions: (1) Under what substrate conditions do these invasive lizards best perform? (2) Are there any within individual performance trade-offs (do lizards who run faster on one substrate run slower on another)? (3) What aspects of morphology most directly affect sprint performance under different conditions? We measured sprint speed with a full-factorial design of substrate type (cork bark, artificial grass, and sandpaper), sprinting elevation (level, incline), and obstacles (presence, absence). We also measured a suite of body dimensions important for locomotion, including tail length and limb dimensions. Lizards performed best on artificial grass without obstacles, but on cork with obstacles. Surprisingly, lizards consistently performed better running uphill compared to a flat track on all substrates. We also found significant negative correlations among all substrates, though strongest between sandpaper and the other two substrates. Finally, the advantage of larger body size in lizards disappeared when obstacles were present. These results demonstrate the complex limitations and trade-offs shaping organismal performance and provide insight into the mechanisms allowing colonization of novel environments.