Some of the esteemed gyms with branches all over Delhi are
1-Golds gym , probably one of the best ones know globally
2-Team Iron champs,grew out from obscurity to now boasting many of the candidates for Mr India and other body building competitions
3-Cult Fitness-relativly new and a tad bit expensive but rightly so especially since its one of the first of it's kind that focuses on the overall development as an athlete (sponsored by the likes of tiger Shroff )