Primary dysmenorrhea is defined as painful menses in women with normal pelvic anatomy and regular ovulatory cycles that usually begins during puberty or adolescent phase. Primary dysmenorrhea affects the women at the age of 16-25 years. Menstrual pain starts after 6 to 12 months after menarche, once the cycles are regular. Symptoms last for about 1 - 3 days of menstruation. Primary dymenorrhea is characterized by cramps, aches or dull pain in the supra-pubic region with or without radiation to lower back, abdomen, medial thigh or upper leg. The chief etiological factors as described by previous researches have been psychic and emotional, fatigue, postural defects and weak abdominal muscles. Hollow back and poor abdominal support lead to increased pressure on pelvic organs and a probable impairment of circulation. Therefore, development of the muscles of the abdominal wall is generally recognized because of the role it plays in maintaining a correct body posture and in supporting the organs in the abdominal cavity. Through this study we will try to explore the abdominal muscle strength, power and endurance in women with primary dysmenorrhea. Also in this study we will explore the effect of alternate treatment technique  (ie Yoga and structured exercises) to reduce pain, improve muscle performance, and quality of life in primary dysmenorrhea. Subjects will be allocated randomly into two training groups (yoga and structured exercises). Then a pre - test will be performed on the third day of the menstrual cycle  before beginning with the intervention. Pre - test will involve testing the levels of pain, muscle performance (strength, power, flexibility and endurance), stress and quality of life. Study involves 3 week long intervention period. Then 2 post tests will be conducted on the third day of  second and third menstrual cycles.