Blitz the dangerous body fat stores that you can't see - and attack proof your heart
Although visceral fat clings to your internal organs, its grip is not particularly strong. When you decide to take action – through diet, running or another form of exercise – your body first uses the fat stores that are most harmful to your health.
Starting with the lipids in your blood, you then reduce the dangerous fat in your liver, followed by visceral fat in the abdomen, and then finally the subcutaneous stuff you can pinch between your fingers.
So which tactic is the most efficient at hunting down the hidden killer? “For me, there is no doubt that hypocaloric diets are the quickest way to remove this tissue,” says Professor Eric Ravussin, who studies obesity at the Pennington Biomedical Research Centre in the US. That means a dramatic cut in the amount of calories you take in – a scientifically backed crash diet if you will.
In one of Ravussin’s studies, obese patients lost an average of 12.6kg after 10-16 weeks on a hypocaloric diet. But as with any crash diet, this is best as a short-term measure for the clinically obese rather than a realistic choice for people who – let’s be honest – lack the willpower to stick to low-calorie diets long-term. And guess what happens when you quit? A study by Duke University in the US found that non-exercisers see an almost nine per cent gain in visceral fat in just six months.
“People who are able to include exercise in their lifestyle are more likely to be successful in the longer term,” Ravussin says. Still, you’ll need to go for more than a stroll. In the Duke study, people who exercised the equivalent of walking or jogging 11 miles per week didn’t gain any visceral fat. But those who jogged 17 miles a week successfully reduced both their visceral and subcutaneous fat.
This is why running is an effective weapon against toxic blubber; most of us can keep it up. The steady and sustainable weight loss you see when you lace up your running shoes ensures your internal organs are not surrounded and infiltrated by fat – even if sometimes you can’t see the difference.
One remarkable study involving runners showed exactly how this happens. In 2009, researchers from the University Hospital of Ulm in Germany followed entrants of the Trans Europe Footrace, a 4,500K odyssey from southern Italy to northern Norway – each carrying with them a mobile MRI unit. Every three or four days the runners, presumably grateful for a chance to put their feet up, underwent a full body scan that allowed scientists to track how their body composition changed as the race went on.
The results were impressive. Over the 64 days of the race, runners lost half their total body fat. Better still, the first thing to start disappearing was visceral fat, 70 per cent of which had gone by the end of the event.
When the research was published, Dr Uwe Schütz, who led the study, remarked, “Much of what we have learned can also be applied to the average runner. When you just begin running, the effects of fat reduction are more pronounced than in athletes who have been running their whole lives.”
High intensity training
So if your goal is to run off your visceral fat, how should you train? Research shows that to reduce fat tissue, especially in the abdomen, the most effective training technique is short bursts of high-intensity training. A study published in the journal Medicine & Science in Sports & Exercise compared the reduction of visceral fat in people training at different intensities.
Some participants continued with their regular exercise, some trained at or below their lactate threshold, others at high-intensity, each for five days a week. The training time was adjusted for each session so that all the participants burned off the same number of calories. Crucially, only those who trained at a high intensity saw significant reductions in their visceral fat.
High-intensity intervals may be quick and effective, but most researchers concede that they are the exercise equivalent of a crash diet. The eye-watering effort involved can put people off, especially if you’re a new runner or have been inactive through injury. “You run 400m at 90 per cent of your VO2 max and then walk the next 400m – for some people, I think it’s unrealistic,” says Ravussin.
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