Latency in virtual reality (VR) can decrease the feeling of presence and body ownership. How users perceive latency, however, is plastic and affected by the design of the virtual content. Previous work found that an avatar's visual appearance, particularly its perceived fitness, can be leveraged to change user perception and behavior. Moreover, previous work investigating non-VR video games also demonstrated that controlling avatars that visually conform to users' expectations associated with the avatars' perceived characteristics increases the users' latency tolerance. However, it is currently unknown if the avatar's visual appearance can be used to modulate the users' latency sensitivity in full-body motion-tracked VR. Therefore, we conducted two studies to investigate if the avatars' appearance can be used to decrease the negative impact of latency. In the first study, 41 participants systematically determined two sets of avatars whose visual appearance is perceived to be more or less fit in two physically challenging tasks. In a second study (N = 16), we tested the two previously determined avatars (perceived to be more fit vs. perceived to be less fit) in the two tasks using VR with two levels of controlled latency (system vs. high). We found that embodying an avatar perceived as more fit significantly increases the participants' physical performance, body ownership, presence, and intrinsic motivation. While we show that latency negatively affects performance, our results also suggest that the avatar's visual appearance does not alter the effects of latency in VR.