Have you recently carried heavy shopping bags up a few flights of stairs? Or run the last 100 metres to the station to catch your train? If you have, you may have unknowingly been doing a style of exercise called high-intensity incidental physical activity.
It’s that time of year when many are trying, and some are failing, to live up to their New Years’ resolution of losing weight. Many of these probably include resolutions to be more physically active in striving for this goal. But first, there are some common misconceptions about exercise and weight loss that need to be addressed.
Everybody knows that to lose weight you need to eat less or exercise more – or ideally do both. The evidence supporting the benefits of regular exercise and eating less is overwhelming, but for people looking to lose weight, it remains unclear whether there are extra benefits to be gained from increasing the intensity of workouts.
People who regularly go on diets tend to lose weight initially but bounce back and even gain weight after stopping the regime. This phenomenon – dubbed yo-yo dieting – is associated with changes in metabolism and is one reason why the vast majority of calorie-based diets fail. But exactly what causes these metabolic changes has remained a mystery – until now.
Despite massive government, medical and individual efforts to win the war on obesity, 71 percent of Americans are overweight. The average adult is 24 pounds heavier today than in 1960. Our growing girth adds some US$200 billion per year to our health care expenditure, amounting to a severe health crisis.