SINGAPORE - A jogger in his 50s was found lying on the ground along the MacRitchie Nature Trail near Singapore Island Country Club (SICC) on Saturday (Aug 12) morning.
The Straits Times understands that he suffered from cardiac arrest and later died in hospital.
A Singapore Civil Defence Force spokesman said it received a call for assistance at 240 Sime Road - SICC's address - at around 11.05am, and sent a fire bike and an ambulance to the scene.
The man was conveyed to Tan Tock Seng Hospital, added the spokesman.
A fellow jogger, Mr Patrick Yap, told The Straits Times on Sunday that he was about to complete his run when he saw the man, who wore a blue singlet and black shorts, lying on the ground in the distance.
"I just happened to pass SICC, and saw from afar that there was a man lying on the green patch of grass, just beside the running path," said Mr Yap, who is self-employed in the recruitment industry.
Together with another female jogger who was approaching from the opposite direction, they went over to attend to him but found him completely unresponsive. Mr Yap then called for ambulance, before another family stopped to help.
"The wife was a former nurse, so she put him in a recovery position. That was when he could breathe for abit, grasping for air. We didn't do CPR as there was a faint heartbeat," he added.
"But about two or three minutes later I noticed he stopped breathing, so that was when we started compressions. An SICC buggy happened to be driving by, and we shouted at the staff to get the AED (automated external defibrillator)."
Mr Yap revealed that the man, who only had a set of car keys on him, was unconscious when taken into the ambulance.
When a person is exercising, blood pressure and heart rate go up, and could cause cholesterol deposits in the arteries to get disrupted, said Dr Kenneth Ng, a cardiologist from the Novena Heart Centre. This means the deposits get dislodged, causing a fissure, or a cut, in the artery.
"This would cause a blood clot to form in the artery, leading to a heart attack," Dr Ng added.
While cholesterol deposits can form in men and women of all ages, the accumulation of such deposits in an older person could make the patient more susceptible to suffering a heart attack while exercising, he added.
If someone encounters a patient suffering a heart attack, an ambulance should be called immediately, and cardiopulmonary resuscitation administered if the patient is unconscious. If the patient is conscious, putting him in a recovery position so he can breathe without choking is also a good step. Administering crushed aspirin if available could also help to thin the blood, said Dr Ng.