Understanding the methods by which cells move is a fundamental problem in modern biology. Cell locomotion is integral to physiological processes such as wound healing, cancer metastasis, embryonic development, and the immune response. Recent evidence has shown that the fluid dynamics of cytoplasm can play a vital role in cellular motility. The slime mold Physarum polycephalum provides an excellent model organism for the study of amoeboid motion. In this research, we develop a computational model of crawling Physarum. Our model incorporates the effects of the cytoplasm, cellular cortex, the internal cytoskeleton and adhesions to the substrate. Of particlary interest are stresses generated by cytoplasmic flow and how transmission of stresses to the substrate is coordinated. In our numerical model, the Immersed Boundary Method is used to account for such stresses. We investigate the relationship between contraction waves, flow waves, adhesion, and locomotive forces in an attempt to characterize conditions necessary to generate directed motion. Cytoplasmic flows and traction stresses generated by the model are compared to experimentally measured stresses generated by Physarum.