SINGAPORE – There are health benefits for a person to engage in short spurts of physical activity, each lasting 30 seconds, done three times a day for three days a week. This is contrary to conventional thinking that aerobic exercise has to be carried out in bouts of at least 10 minutes each to be effective.
In an interview with ST Health Check podcast, Clinical Assistant Professor Ivy Lim, a senior consultant and chief of the Department of Sport and Exercise Medicine at Changi General Hospital (CGH), said that sprint interval training, which is a form of high-intensity interval training, may be helpful to individuals who are unable to participate in prolonged periods of exercise.
A 2020 CGH study had found that six weeks of 30-second sprints – three bouts per day, separated by around four hours of rest, for three days per week – were effective in improving aerobic fitness of healthy individuals by around 8 per cent, compared with a non-training group.
It also helped to improve cardiovascular fitness and lower-limb muscular strength.
Sprint interval training, typically lasting less than one minute each time, is most commonly done on a cycle ergometer or stationary exercise bike, said Prof Lim. It involves bouts of “all-out” effort, followed by periods of rest or light active recovery between each sprint.
Those with knee issues may have problems doing this potentially intensive exercise, especially if it is an activity they are not used to, she added.
Sprint interval training was included as one of the interventions in a CGH pilot six-week lifestyle intervention programme aimed at improving its staff’s physical activity engagement, eating behaviours as well as their overall mental well-being.
Participants in the programme also reported modest weight loss, though this effect is not universally seen across all sprint interval training programmes, said Prof Lim.
In the podcast, she also discussed the need to combine exercise with diet, if one is exercising for weight loss. Exercise appears to reduce visceral or hidden fat in overweight and obese adults, she added.
There have also been studies that show that physical training on its own rarely achieves a loss of more than 3 per cent of a person’s original weight. However, if diet and physical activity are combined, a person can potentially lose 5 per cent to 15 per cent of his original weight, Prof Lim said.
Listen to the podcast to find out what you can do to fulfil 150 to 300 minutes of moderate-intensity physical activity a week and how to tell if you are engaging in moderate-intensity activity.
