A no-pain workoutq; Calculate your calorie count and lose lbs the easy way.
HOW many times have you blamed your expanding waistline on a slow metabolism?
Or envied a skinny model and wished you had her ultra-fast metabolic rate?
Most of us talk about our metabolism from time to time, but few of us understand what it means or what it does.
Fortunately, it's not that complicated. Metabolism controls all the body's chemical reactions, which create or use up energy or calories. The amount of energy you use is your metabolic rate.
We all need different amounts of energy. How much depends on just four factors - whether you are male or female, how old you are, how much you weigh and how active you are.
The first three affect what scientists call our base metabolic rate (BMR) - the energy we use when we're resting.
Dr Susan Jebb, from the Medical Research Council's Human Nutrition Research Unit in Cambridge, says: "Your BMR is very predictable according to your gender, age and body weight. People whose metabolism isn't determined by these factors don't exist."
When it comes to weight, contrary to popular belief, the heavier you are the higher your BMR. This is because the more you weigh, the more energy you need to sustain those extra cells. For example, a gain of 22lb in an adult would result in an increase in BMR of about 120 calories per day.
Also, the more muscle you have, the higher your BMR. This is because muscle has a higher metabolic rate than fat. Sadly, women are at a disadvantage because they usually have a higher proportion of body fat - even at a healthy weight - compared with men, who have more muscle.
Unfortunately, as we get older we start to lose muscle as part of the ageing process. And this means our BMR slowly decreases with age.
So which of these can we control? "There's not much you can do to alter your BMR," says Dr Jebb. "Virtually the only aspect of your metabolism you can influence is your level of physical activity."
In other words, if you exercise regularly, you'll use up more calories and have a faster metabolism than if you're lazy. And by expending more energy than you take in through food and drink, you'll lose weight.
Unfortunately, as a nation, we're becoming less and less active. A recent report by the National Audit Office says the extra physical activity involved in daily living 50 years ago compared with today adds up to the equivalent of running a marathon every week.
Dr Liz Evans, of the Association for the Study of Obesity and scientific director at Slimming Magazine Clubs, says: "Having a higher metabolic rate by increasing physical activity should speed up weight loss, or help you lose weight." But this doesn't mean you have to spend hours on end at the gym. Dr Evans says: "Start by walking to work and taking the stairs instead of the lift."
Obviously cutting down on calories will help you lose weight, but this can also temporarily lower your metabolism, especially if you seriously restrict your food intake. And ultimately, this will slow down your weight loss.
Dr Evans says: "Consuming too few calories is a false economy. Your body goes into starvation mode and adapts to its new lower calorie intake by lowering its metabolic rate. Never have less than 1000 calories a day."
So crash diets don't work, and rather than kicking your metabolism into action, they slow it down.
What about the many pills and potions on the market that claim to stimulate metabolism?
Sadly, there's no evidence they work at all. If you see any improvements it's likely to be due to the diet advice that comes with them. Dr Evans says: "Don't kid yourself. These pills are expensive and ineffective."
What's the solution? The fact is there are no miracle cures. Simply take regular exercise, avoid low-calorie diets and eat a healthy, balanced diet.
That's what will help you lose weight... and keep it off.
What your energy intake should be?
According to the Department of Health, the average woman between 19 and 50 needs 1940 calories a day to maintain her weight. But to find your calorie needs, get your calculator out and follow the steps below.
Step 1 Calculate your basal metabolic rate (BMR)
Use the equation below that relates to your age. Add your weight (you'll need to know how heavy you are in kgs: 1kg = 2.2lb) and do the calculation.
Women 18-29 years BMR = 14.8 X weight (kg) + 487
Women 30-59 years BMR = 8.3 X weigh (kg) + 846
Step 2 Work out how active you are
Find the 'at leisure' description that fits your life on the table, right. Move along that line and pick an appropriate 'at work' figure. Eg, if you are not active at leisure or work, your figure is 1.4.
At Leisure At work
Non active Active
Non active 1.4 1.5
Moderately 1.5 1.6
Very active 1.6 1.7Step 3
Calculate your total calorie requirements
Multiply the value from Step 1 by the value from Step 2. The figure you get will tell you how many calories you need each day to keep your weight steady.