A seal assembly and method of forming a seal assembly provides a seal body having reduced strain during use, thereby increasing service life. The seal body may be formed within certain parameters, such as ranges of height-to-thickness and offset-to-height ratios, which have been found to reduce strain. Additionally or alternatively, the seal body may be modified from an initial configuration to a pre-strained configuration by axially displacing an inner section of the seal with respect to an outer section of the seal, which also reduces strain.