Recently was filling up questionnaire for my mum and came across 'heart related problems' and in the list of symptoms was 'dizzy spells' recently I tried a bicycle in the store and after riding it for just a 10 minutes got little dizzy and hole day felt like this in the past a had a mild heart attack in 2001 since that I cant do lots of physical activities but i do not know why should I have problem riding bike slowly and for a pleasure but every time I did I had little uncomfortable feeling in my chest and now happened this I felt dizzy. can anybody tell me should I forget about bike all together to save my self or there is a solution..