Simply to make a show of gymnastics is not perfection of yoga. Yoga means control of the senses. If you indulge your senses unrestrictedly but make a show of yoga practice, you will never be successful.
Krsna Consciousness: The Topmost Yoga System
By His Divine Grace A.C. Bhaktivedanta Swami Prabhupada
Chapter One
The Perfection of Yoga
Lord Kṛṣṇa, the Supreme Personality of Godhead, speaks about the topmost system of yoga in the Sixth Chapter of Bhagavad-gītā. There He has explained the haṭha-yoga system. Please remember that we are preaching this Kṛṣṇa consciousness movement on the authority of Bhagavad-gītā. It is nothing manufactured. The bhakti-yoga system is authorized, and if you want to know about God, then you have to adopt this bhakti-yoga system because in the Sixth Chapter of Bhagavad-gītā it is concluded that the topmost yogī is he who is always thinking of Kṛṣṇa within himself.
The Hare Krishna Movement 