It’s important to be aware that there are very many different ‘forms or schools’ of Yoga.
And these range from very gentle yoga classes which would not really ‘work out’ the body as such, and at the other end of the physical spectrum there are ‘ashtanga vinyasa’ classes where you will be sweating after 30 minutes and keep going solidly for 2 hours with dynamic flowing challenging postures.
If you would like to build up your chest (or at least strengthen and improve definition) then Ashtanga Vinyasa yoga classes may be where to start looking.
However, it is even more important to be aware of the more traditional forms of yoga, which do not pup port to be ‘fitness systems’ although, certainly fitness and health would be side effects through daily practice.
These traditional systems of yoga, aim to transform one’s whole being, lifting it out of animalistic desire and ego driven way of living, into a more enlightened heart centered awareness which is more loving, ‘caring of/for others’, peaceful, blissful and much more that goes beyond words.
These are very lofty aims and traditional yoga is a huge body of techniques and practices, and way of life and unfolds differently for each human being as they diligently follow the practices each day, and try to bring the true aspects of yoga into every minute of every day.
But if it’s fitness you are after, then maybe good to start with Ashtanga Vinyasa which is about 100 years old… which is probably old enough for most westerners to call traditional
And if you find a good ‘ashtanga vinyasa’ teacher who also practices meditation and the other limbs of yoga, then this can be a wonderful beginning to this ever changing and flowering path that each yoga practitioner under takes.
The whole conversation or subject area can become quite confusing, as the more traditional form of yoga is sometimes referred to as ‘Ashtanga yoga’ meaning the ‘8 limbs of yoga’ and this term was used by Patanjali approx 1000 years ago in his ‘enlightened description’ of the ‘yoga path’ which has been followed by aspirants for over 5,000 years.
But about 100 years ago, Krishnamacharya taught what he referred to as ‘ashtanga vinyasa yoga’ which was mainly a subset of the 8 limbs of yoga…(mainly 1 limb … asana) but weirdly coined the phrase ‘Ashtanga vinyasa yoga’ to describe it.
I can only hope that he was teaching this practice to young teenage boys in order to strengthen them physically, but also planting the seed in these young men that there are in fact 7 other limbs of yoga which ‘hopefully’ they would all follow.
Anyhow much of my musings here are only coming from a 50 years old and like any other human enmeshed in desires and un-enlightened existence… i can be wrong too