30-second secret to lifelong health

THIRTY-SECOND bursts of intense activity may be better at warding off heart disease and related conditions than hours spent pounding the pavements or at the gym, according to a new exercise regime to be unveiled this week.

The interval training regime developed at Heriot-Watt University involves four half-minutes of maximum-effort cycling or running interspersed with minutes of rest at least twice a week.

The team behind the regime believe the high-intensity method is more effective at burning fat than long daily workouts and also dulls rather than sharpens appetite.

As well as improving fitness levels, initial studies suggest the technique may also help prevent diabetes and cut the risk of heart disease.

Professor James Timmons, who is leading a global study into the effectiveness of the method, has now been awarded a £5 million European grant to develop the regime further.

The latest results will be broadcast on the BBC’s flagship Horizon science programme on Tuesday – in an episode titled The Truth About Exercise – and are expected to fuel debate on the merits of high intensity exercise against more conventional and time-consuming methods. The research team hopes it will improve the health of the nation by making it easier for everyone to find time to exercise.

According to Timmons, who has now moved from Scotland to Birmingham University, high-intensity interval training (HIIT) moves glucose from the blood into muscle tissue where it is burned off as energy rather than converted to fat, thus providing a more effective fitness regime than an hour-long gym session.

Thanks to the grant from the European Union’s FP7 (Seventh Framework Programme), its main body for funding quality-of-life research in Europe, Timmons and his team will be able to study the effects of HIIT on the human body in more detail. He said: “HIIT is really good at improving glucose uptake into the muscles in a very, very short time.

“With really intense exercise, you release hormones that can help break down fat. This may help burn that fat over time, after HIIT is done. Also, we think, but don’t know, that HIIT will subdue appetite, while traditional exercise will stimulate appetite. This last point is key and will be researched by our team.”

HIIT workouts can be done on an exercise bike, through running up stairs, or merely by sprinting on the spot.

“The key is to do four 30-second sprints on an exercise bike at your maximum effort, with short rests in between bursts,” said Timmons. “The whole thing should take about four minutes. Doing this, even just twice a week, will bring clear benefits.”

The initial study was carried out in Edinburgh and monitored 16 average and relatively sedentary 20-year-old men before and after a two-week training period.

They performed four 30 seconds of sprint cycling, with rest intervals, three times each week, making a total of six exercise sessions. Afterwards the men were given a drink containing glucose and the study monitored how their bodies processed this. After two weeks, the subjects displayed a 23 per cent improvement in how effectively glucose was removed from their bloodstreams.

“In two cases, it was up to a 35 per cent increase, which is dramatic,” said Timmons. The study appeared to suggest the effect lasted up to ten days after the last round of exercise.

A number of organisations are involved in the four-year MetaPredict project, including Glasgow biomarker firm OracleBio, and Duke University in the US. Martin Gibala of McMaster University in Ontario, which is also taking part, said: “A growing body of evidence demonstrates that HIIT can serve as an effective alternative to traditional endurance-based training. Such findings are important given that ‘lack of time’ remains the most commonly cited barrier to regular exercise.”

The findings have particular importance in Scotland, which still has a stubbornly poor diet-and-exercise related, high rate of heart conditions.

“The exercises reduce all the things we know that cause cardiovascular disease,” added Timmons. “This approach may help people lead a healthier life, improve the future health of the population, and save the health services millions of pounds simply by making it easier for people to find time to exercise.”

The short-burst regime contrasts markedly with government exercise advice which suggests at least three 20-minute sessions of vigorous activity every week. Some experts believe even this is too little.

GP and obesity expert Dr Ian Campbell, chair of the National Obesity Forum, said: “There’s overwhelming evidence that for good health you need to do 30 minutes of exercise and to lose weight this needs to be 60 minutes a day. And exercise on its own is not enough to affect weight loss, it has to be done with dietary control. Dieting is the best way to lose weight, but exercise is the key to keeping it off.”

Another potential stumbling block is that HIIT only burns up to around 250 calories a week, far less than regular gym sessions. However, Timmons hopes the research will show it also suppresses appetite, meaning less calories being taken in at the outset.