Your essay can be about Yoga and any health issue that motivates you. For example: Yoga for the Handicapped, Pre and Postnatal Yoga, Yoga for Seniors, Yoga for Kids, Yoga in School Systems for Physical Education, Yoga for Drug Rehabilitation, Yoga for Menopause, Yoga for Chronic Fatigue Syndrome, Yoga for Psychotherapy, and the list goes on.
Your own life experiences on Yoga and any health topic, injected into your essay, is always more interesting than another author’s experiences and opinions. At the same time, you will need some solid Yoga, health, fitness, or medical resources to back up your findings.