The answer to this is false. The lipids may be too large to pass through the cell membranes if they do not dissolve but the thing is, they do dissolve. This means that even if they are too big, they would be able to get through. The lipid will always dissolve in solvents that are non-polar by nature.
There are also some types of lipids that can be found in the outer layer of your cells. There are also some lipids that will serve as the storage compounds of the body. One example of this is triglycerides. They are responsible for storing energy that the body may need in the long run. This explains why even if you are tired, you still have the energy to move.