(A) Vesicle shapes change induced by the interplay between the elastic bending energy of the membrane and the swim pressure. Color bar represents the local membrane mean curvature H(B). Phase diagram as a function of the self-propulsion speed $v_0$ and the reduced volume $\widehat{V}$. (C) Free energy $-\text{log}P\widehat{V}$ as a function of the reduced volume $\widehat{V}$ for three values of $v_0$. Reprinted with permission from Ref. [81]. Copyright©2019 American Physical Society.