SINGAPORE - Having a medical check-up before starting on any sports regimen, such as running or swimming, could be important.
In the United States and Italy, screening is mandatory if students or young adults want to participate in college-level sports, said Dr Kenneth Ng, a consultant cardiologist at the Novena Heart Centre.
In Singapore, the Government also requires medical check-ups for young men before they enlist for national service, he added.
Dr Ng believes this could be taken further and that, in fact, anyone who is thinking of starting a high intensity sports regimen should undergo a sports physical, especially those 40 years and older.
Such a physical would help to rule out some causes most commonly responsible for sudden death.
For someone above the age of 35, this would be coronary artery disease, he said.
It is rare for someone under the age of 35 to collapse suddenly while exercising, but a few things could cause this.
One is hypertrophic cardiomyopathy - a condition in which the heart muscle thickens and this is usually caused by gene mutation - which makes it more difficult for blood to leave the heart. The organ, in turn, has to work harder to pump blood around the body.
Another is arrthymogenic right ventricular dysplasia, also a disorder of the muscular wall of the heart.
This condition causes part of the wall to break down over time, increasing the risk of an abnormal heartbeat.
The long QT syndrome, a potentially fatal heart rhythm disorder that has no known cure, is another cause, said Dr Ng.
Studies have shown that sportsmen who undergo a medical check-up or a sports physical before embarking on a high-intensity activity have fewer incidents or deaths than those who do not.
One well-known study from Italy compared two eras - before and after pre-participation screening for athletes.
The researchers analysed the changes in incidence rates and causes of sudden cardiovascular death among 42,386 young athletes (aged 12 to 35 years) undergoing pre-participation screening between 1979 and 2004.
During the study period, the annual incidence of sudden cardiovascular death in athletes dropped by 89 per cent - from the period between 1979 and 1980 when screening first started, to the period between 2003 and 2004.
This study was published in the Journal Of The American Medical Association in 2006.
Sports physical checklist
The sports physical should include going through a person's medical history to spot any family history of sudden cardiac death and to check if the person has previously experienced fainting spells, chest pain or breathlessness when he exerts himself, said Dr Ng.
A physical examination would, for example, look out for any murmurs or abnormal chest pulsations (abnormal heaving of part of the chest).
A complete medical sports physical can be done by a sports physician at any sports medicine facility or health assessment centre, said Ms Pauline Leong, principal physiotherapist at Singapore General Hospital.
These centres, which are found in most hospitals, are staffed with doctors who can do all types of health screening, including pre-screening for sports participation.
Other than electrocardiograms or treadmill stress tests, some centres may also be able to do a test to determine a person's maximum oxygen intake (VO2max), which is also an indicator of aerobic fitness.
This is done on a treadmill, bike or rower that is operating at an increasing speed, said Ms Leong.
As the body works harder, the lungs will need to draw more oxygen to supply the muscles. The body will reach exhaustion when the lungs are working at maximum capacity.
The VO2max measurement will then be taken at this point.
Those who are fitter will register higher VO2max values as they can exercise more intensely than those who are not as well-conditioned.
Those who are planning to start on an exercise regimen can also see a sports physiotherapist to have a thorough musculoskeletal screening and assessment, said Ms Leong.
The sports physiotherapist will assess the joints, muscle length and strength, agility and quickness to identify any muscle imbalances.
He can then advise on the stretching and strengthening exercises that the person has to do in order for him to perform in the chosen sport efficiently while reducing the risk of repetitive injuries, said Ms Leong.
Taking part in any sport involves a certain amount of risk.
Making sure you are in the best shape possible will ensure that you enjoy a long sporting life, she added.
The American College of Sports Medicine recommends that you take the following questionnaire - to help determine if you are ready to begin an exercise routine or programme - before starting an unfamiliar regimen.
1. Has your doctor ever said that you have a heart condition or that you should participate in physical activity only as recommended by a doctor?
2. Do you feel pain in your chest during physical activity?
3. In the past month, have you had chest pain when you were not doing any physical activity?
4. Do you lose your balance from dizziness? Do you ever lose consciousness?
5. Do you have a bone or joint problem that could be made worse by a change in your physical activity?
6. Is your doctor currently prescribing drugs for your blood pressure or a heart condition?
7. Do you know of any reason why you should not be participating in physical activity?
You should consult a physician and be assessed before embarking on an exercise programme or new sporting activity if you have answered "yes" to any of the questions, are above 40 years of age, lead a sedentary lifestyle or suffer from heart problems and hypertension.
Your doctor can give you a better indication of your fitness level so you can start exercising at an appropriate level.
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