Habitually sedentary individuals may have unknown cardiovascular disease so should increase physical activity very gradually – suddenly doing vigorous intensity activity may increase risk of myocardial infarction in this inactive group by 100-fold.
Those with active symptoms such as chest pain, acute breathlessness, palpitations or signs of heart failure may have serious underlying pathology and should be referred for specialist investigation.
Thompson PD, Arena R, Riebe D, Pescatello LS, Medicine ACoS. ACSM’s new preparticipation health screening recommendations from ACSM’s guidelines for exercise testing and prescription, ninth edition. Curr Sports Med Rep. 2013;12(4):215-217.