Dorothy Alden Becker Lineer (1900 – 1989) was an American surfer and competitive swimmer.

Given a grim diagnosis by a doctor, her family moved her to Santa Cruz, California for a "nature cure" and set her on a strict regiment of exercise including swimming and diving.

[2] She sailed to Honolulu in 1915, at the age of 15, to compete against champion American swimmer Ruth Stacker, who held the record of 50 yards in 31 seconds.

[6] In a letter to Bernarr Macfadden, Becker credits exercise with saving her life from illness.

The letter is one of the earliest known references to a woman using resistance training to improve her sports performance.