^I am not aware of any scientific data about recreational opiate use and cardiovascular activity, but what I do know is that exercise had helped me recover from a bad untested molly experience from last year.
Cardio exercise strengthens nor only the heart anf lungs but also the brain function. As already mentioned in other threads, it balances the neurotransmitters in the brain and also through sweating, releases unwanted toxins out of the body.