A lean body, regular workouts, a low resting heart rate, the ability to run several kilometres or lift heavy weights—all may seem reassuring. (Source: Pexels/ Representational)The gym is supposed to be the place where we go to make the heart stronger. That is what makes the sudden collapse of a 47-year-old doctor in an Assam gym so unsettling. Dr Sahin Rahman, an associate professor at Nagaon Medical College and Hospital, reportedly collapsed while working out and could not be revived.He was young, a doctor and clearly into fitness. “But heart health is not conditional and could be brought on by underlying and unidentified complications, fatal rhythm disturbance, stress, lack of sleep or extreme dehydration. We are increasingly seeing cases of silent cardiovascular disease in people who appear healthy,” says Dr Ranjan Shetty, lead cardiologist and medical director, Sparsh Hospital, Bengaluru. Listen in:The dangerous assumption of looking fitA lean body, regular workouts, a low resting heart rate, the ability to run several kilometres or lift heavy weights—all may seem reassuring. But none of them can point to an undiagnosed heart disease. During strenuous exercise, the heart works harder, blood pressure rises and the demand for oxygen increases. For a healthy heart, this is part of the body’s normal response to exertion. But if there is a vulnerable coronary artery, a significant rhythm abnormality or an underlying structural problem, the sudden increase in cardiovascular demand can, in some cases, trigger a crisis. The exercise session often exposes a problem you did not know of.Why 40s are high riskBy the 40s, a person’s cardiovascular health reflects years of accumulated exposure—to cholesterol, blood pressure, diabetes, tobacco, inadequate sleep, stress, diet, alcohol consumption and family history. Some people carry considerable risk without experiencing a single dramatic warning. This is particularly relevant in India, where heart disease often presents at younger ages than many people expect.The doctor who may not have time to be a patientThen there is stress. Doctors occupy a peculiar position in the health system. They know the symptoms. They know the risk factors. They tell patients to sleep better, exercise, control their blood pressure and check their cholesterol.But the profession itself can make those things difficult. Long shifts. Night duty. Interrupted sleep. Emotional exhaustion. Constant responsibility. Meals taken between patients. Years spent working against the body’s natural clock. But chronic stress and poor sleep can contribute to cardiovascular risk, particularly when they sit alongside other factors.When the workout becomes a stress testA strenuous workout is, in effect, a controlled stress placed on the cardiovascular system. Heart rate climbs. Blood pressure rises. The body releases adrenaline. Muscles demand more oxygen. Most of the time, that is precisely why exercise is good for us.Story continues below this adBut intensity matters. Someone with an undiagnosed cardiac condition may tolerate ordinary daily activity without difficulty and still experience trouble when suddenly pushed to a much higher level of exertion. Heavy lifting, maximal effort, intense cardio, inadequate hydration or simply exercising beyond one’s conditioning can add to the physiological stress.The prescription for one person’s body may not be the prescription for another’s.The warning signs we ignoreSome people have no warning at all. Others do—and dismiss it. Unusual breathlessness. Chest pressure or discomfort. Fainting or near-fainting. Sudden dizziness. Palpitations. An unexplained drop in exercise tolerance.These are not necessarily signs of heart disease. But when they occur during or immediately after exercise, they deserve medical attention rather than an assumption that one is simply tired, unfit or having a bad day.Story continues below this adBegin your cardiovascular risk assessment (cholesterol, blood sugar, obesity, hypertension) much earlier rather than waiting until middle age. Take persistent symptoms seriously. And if you are planning to move from little exercise to extreme exertion, do not assume that enthusiasm is the same thing as preparedness. Get a resting ECG, 2D Echo, stress test or CT coronary scan if you are 35+. Also, every public space should have automated external defibrillators (AEDs) which can revive the patient by resetting the heart and sorting out the rhythm disturbance.