Orthopaedics & Sports Medicine

Appropriate exercise can improve heart and lung function and reduce the risk of chronic diseases. However, reports of exercise-related heart attacks and sudden deaths in the media – especially involving young, seemingly healthy individuals – have led to confusion about the safety and benefits of physical activity.

Exercise-related heart disease
During exercise, the body requires a greater supply of oxygen, which must be supported by a healthy heart and normal blood circulation. Physically fit individuals with strong heart muscles can tolerate varying levels of exercise intensity. With proper preparation and preventive measures, exercise is generally safe and beneficial.

Sudden illness or death during exercise typically occurs in individuals with undiagnosed heart or cardiopulmonary conditions. The most common causes are hypertrophic cardiomyopathy and coronary heart disease. 

Hypertrophic cardiomyopathy/coronary heart disease
Hypertrophic cardiomyopathy affects the myocardium (heart muscle), causing part of it to thicken without a clear cause. When the thickened muscle is located near the aorta, it can obstruct blood flow and lead to irregular heart rhythms. The condition becomes particularly dangerous during exercise due to increased circulatory demands. 

Similarly, individuals with coronary heart disease, characterised by narrowed or blocked coronary arteries, may struggle to circulate blood effectively. As the heart works harder to meet oxygen demands, reduced blood flow can cause chest pains or distress. Those with either condition should avoid prolonged exercise, as exhausted heart muscles and insufficient oxygen supply may result in heart attacks or sudden death. 

Who should have health screening?
Understanding your physical condition and limitations helps prevent overexertion. Unfortunately, many people show no symptoms. Health screening is therefore vital in reducing the risk of exercise-related illness or sudden death. 

Heart health screening is recommended for individuals with: 

• A family history of heart disease
• Chest tightness, dizziness or shortness of breath during exercise
• Diabetes, high cholesterol, high blood pressure, smoking habits or obesity
• A history of drug abuse (e.g. cocaine)
• Use of liquid protein or diets that may trigger dangerous heart rhythms
• Plans for long-term or high-intensity exercise, such as marathon or triathlon training 
   

Two effective screening methods are the Exercise Electrocardiogram (ECG) and heart ultrasound. During an ECG test, you would run on a treadmill while connected to an ECG machine, which records the heart’s electrical activity. A heart ultrasound uses high-frequency sound waves to produce images of the heart, allowing assessment of its structure and function. 

Exercising safely
People without heart disease can take part in various forms of exercise, such as aerobic training to improve cardiopulmonary function or resistance training to build muscle strength. It is important to exercise at an appropriate intensity, which can be determined using your maximum heart rate. Overexertion may lead to fatigue or injury, while insufficient intensity may not yield the desired benefits. A balanced approach is key. 

Anyone with heart disease may also exercise, provided they have recovered from treatment and follow medical advice. Under supervision, they can perform suitable exercises at the right intensity. Even after procedures such as angioplasty or bypass surgery, aerobic activities such as swimming or brisk walking can help restore cardiopulmonary function. Resistance training, including weightlifting, should only be undertaken after proper assessment. 

Exercise-related asthma
Exercise-induced asthma is common among children and teenagers. It typically occurs after several minutes of intense activity in individuals who do not otherwise experience asthma. Symptoms such as coughing, chest tightness, wheezing and fatigue may appear during continuous exertion but often subside after about an hour. 

During intense exercise, breathing through the mouth allows cold, dry air to reach the lungs. The contrast between this air and the warm air inside the lungs can trigger an asthma attack. The airways may swell and produce excess mucus, leading to symptoms. If the inhaled air is polluted or contains allergens, inflammation may worsen and become life-threatening, especially for those with asthma outside of exercise. 

Managing asthma symptoms
A spirometry test can be arranged by a doctor to diagnose exercise-induced asthma. Most cases respond well to medication such as Salbutamol. Another strategy is to manage the duration and intensity of exercise. 

Since symptoms often appear after several minutes and fade after an hour, a longer warm-up may help. This allows the body to gradually adjust to the exercise and may trigger symptoms earlier, enabling the individual to rest and recover before continuing. 

Exercise-related Anaphylaxis
Food-dependent, exercise-related anaphylaxis occurs only when an individual eats a specific food AND exercises within a short while afterwards. The symptoms include shortness of breath, cramps, collapse and unconsciousness. 

The food allergens can be seafood, butter or cheese. Allergy-prone people may not normally have an allergic response to the food, but anaphylaxis is likely to be induced when the food is ingested right before exercise. Although it is a very rare condition, when one suffers from exercise-related conditions that are not related to heart functions or asthma, it can be the underlying cause.