The icon is a picture for the logo of Flex Biceps. The icon is a picture of a human beings arm. The arm has large biceps, which appear to be extended through the process of flexing.
This Muscle icon is made in Material Design style
developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 5,700 icons, all in the same style and quality.