Which of these are christians not allowed to take part in or ociate with?

Christians are not forbid to do any of them, the question is does it honor God or not and what does it say to the 'world'. Can a Christian do yoga? Sure, as long as they are not chanting some Hindu mantra and praying to a false god - but why not just do stretches and just call it that? What would be the implication to a Christians 'witness' if they were chanting a mantra - it may be that they are not really a Christian and giving the wrong impression of what a Christian should or shouldn't be doing.