Can one still go mountain biking when he is diagnosed with acute coronary syndrome?

Not yet.: If your acute episode has been treated, is stabilized, and you are no longer symptomatic; then it could be time to begin an exercise program that builds up your conditioning to the exertion required for mountain biking. You may stick to flat ground cycling as directed by your cardiac rehab program, but you might want to take it easy until you have the "all-clear" from your cardiologist!

Coronary Syndrome.: Not until cleared by the cardiologist who treated the acs. It depends on whether the underlying disease has been corrected or not.