Background: Simulation of physics is something several modern video games use. These simulations are often used to create more believable and realistic environments. Physics-based animations in the form of muscle simulations is one such technique.

Objectives: The aim of this thesis is to investigate three different stages of full-body muscle deformation and observe which of these are preferred. One using no degree of deformation being the control condition and the other two using different degrees of deformation being the treatments. This study is conducted by creating animationswith three different degrees of muscle simulation. These animations are then rendered in Maya as well as put into a small fighting scenario implemented in Unreal Engine 4. A user experiment will be conducted where a number of participants will be asked to choose between different scenarios using two-alternative forced choice. After the user study is completed, the data will be analyzed and used to form a conclusion.

Methods: Implementations needed to create the stimulus was first done in Maya where the meshes, muscles and animations were created. Renders were done in Maya of all animations and a scene was also implemented in Unreal Engine 4 simulating a small fighting game using the assets created in Maya. To evaluate player preference,a user experiment was conducted with 13 participants where each participant was asked to watch 27 scenarios containing two side-by-side comparisons with different degrees of muscle deformation. The user experiment stimulus was created using PshycoPy which also collected the data of user preference. The scenarios where presented in an arbitrary order. The study was held in a room where the participant was undisturbed.

Results: The results showed that no muscle deformation was preferred in all cases where a statistical difference could be found.

Conclusions: While the results show that the control condition is mostly preferred, most cases did not yield a conclusive result. Thus further research in the area is necessary.