The present study examined throughout three experiments the nature of stimulus-response compatibility (SRC) effects related to affordance perception in situations wherein object affordances and response effectors are irrelevant to each other. In the first experiment, using a foot-press response dispositive, we found a SRC effect between the orientation of the graspable part of the presented object and the laterality of the response. In Experiment 2a, we showed that constraining the subject hands in a given position (i.e., a Lego hand shape) during the same task interfered with the SRC effect. In Experiment 2b, participants performed a short training phase with their hands constrained before performing the experiment. This resulted in an inversion of the direction of the SRC effect previously observed. We discuss these results and provide arguments in favor of a specific motor activation account.