With so many people leading a sedentary lifestyle, getting them to be more physically active becomes increasingly important.
Dr Ben Tan, who heads Changi General Hospital's sports medicine department, said: "The list of benefits for being physically active is endless."
Fitness and health are only two of them, said Dr Tan, a former national sailor and president of the Singapore Sailing Federation.
The 2010 National Health Survey found that 39.1 per cent of Singaporeans were physically inactive and 11 per cent were obese. Obesity increases the likelihood of conditions such as high blood pressure, diabetes and heart disease.
Singapore's Health Promotion Board and the American College of Sports Medicine recommend 150 minutes a week of moderate physical activity, or 75 minutes of vigorous physical activity to reduce the likelihood of getting such "rich man" diseases.
Finding your target heart rate
But what does "moderate" or "vigorous" mean?
It all depends on your heart rate. This can be measured by a heart-rate monitor, basically a chest strap that connects to a GPS running watch, which will let you monitor your heart rate during a workout.
The exercise intensity that is right for you depends on your age. The rule of thumb is to subtract your age from 220 to get your maximum heart rate, then calculate your target heart-rate zones.
The moderate-intensity zone is 50 to 70 per cent of your maximum heart rate; vigorous intensity would be 70 to 85 per cent of your maximum heart rate.
So if you are 40, your maximum heart rate would be 180 beats per minute. This means your target heart rate for moderate exercise should not exceed 126 beats per minute; or 153 for vigorous exercise.
Miss Fay Hokulani, a certified personal fitness trainer and model, said: "If you are in zones that are too high, your workout will exhaust you and put you at risk of injury. If too low, you will not be pushing yourself enough to develop the base fitness you need to get healthy."
Many of the newer fitness trackers and smartwatches have heart-rate monitors built in. But most lack built-in GPS and need to be paired with a smartphone. And carrying a smartphone might be a hassle.
Miss Hokulani is glad not to have to fiddle around with an app on her smartphone while working out.
"That can be quite distracting. It's more convenient and lighter to wear a watch," she added.
A GPS running watch is a very personal choice. Some may want it to have more features so that the device is like a fitness tracker. Others may need to track a triathlon, or only to track runs.
Digital Life put five GPS running watches with heart-rate monitors through their paces to see how they perform on a 400m stadium track on a clear day, for control purposes; and also in an HDB neighbourhood to see if buildings and trees would cause a loss in GPS signal.