Jillian Michaels is a well-known American personal trainer, television personality, and author. She gained fame as a coach on the reality TV show The Biggest Loser, where she helped contestants lose weight and improve their fitness. Michaels is recognized for her tough-love approach and motivational style. In addition to her television career, Jillian has released several fitness DVDs and authored books on health and wellness. She has developed workout programs and fitness apps, making her a prominent figure in the fitness industry. Her focus is on promoting a healthy lifestyle through exercise and nutrition.