
Swimmer / Ectomorphs are typically characterized as being thin or slim, and usually have narrower shoulders, flatter chests and stomach. If you find most clothing to be too large in the shoulder and chest areas, then this is likely your body type.
Bodybuilder / Mesomorph are typically characterized as jacked or muscular, and usually have broad shoulders, larger chest and a medium waist. If you find most clothing to be too tight in your shoulders and/or chest area, this is likely your body type.
Linebacker / Endomorph are typically characterized as bulky or heavy, and usually have medium sized shoulders and chest, with a larger waist. If you find most clothing to be too tight in your waist area, this is likely your body type.