I am 59 years old and suf­fer from angina, for which I am on med­ic­a­tion. My doc­tor advised me to take more exer­cise, so I go to the gym once a week but as soon as my heart rate gets to around 100 the angina pains start. I don’t feel any bet­ter, have not lost any weight and can­not see that it is going to help. Should I push myself harder?...