Diets don't work: How much should I weigh?
Our Diets don't work blog is by Ascot-based personal trainer Adam Atkinson. He will be offering health and fitness advice on our websites each month.
A combination of factors determine our weight, and that’s why it’s difficult to set an exact ideal weight that applies to everyone.
There’s a range of healthy body weights, and your aim should be to keep within this healthy range. This means an end to aspiring to one magic weight that you think you should be. Your target weight is not a constant either; it may change depending on your circumstances and age.
Many people have a distorted perception of what constitutes a healthy body weight. We’re surrounded by images of celebrities and models, many of whom are underweight. Comparing yourself with these images isn’t helpful.But comparing yourself to friends and family isn’t that useful either, because as obesity becomes more common our perception of ‘average’ weight may in fact be too heavy.
It’s important to make an objective assessment of your size. Looking at yourself in the mirror might also not be the best way to assess whether you’re a healthy weight either, although it’s a step in the right direction.
There are a number of ways you can work out if you’re within a healthy weight range. You need to get an accurate idea because it’s easy to underestimate or overestimate your own weight.
1 - Body Mass Index or BMI. You can check your body size using the body mass index which assesses your weight in relation to your height. Although this method is much touted by the media and medical professions (it is used by the NHS) BMI is, in the eyes of many trainers and health professionals (including us), a flawed and often misleading system.
Although it can be a useful guide if you are an average height, size and build, the BMI makes no allowance for individual variations in body frame, shape, muscle mass and bone density. As a good example I will take myself-I am 5’9, very fit, strong and healthy; I weigh 93kg (14st 8lbs). My BMI is therefore 31, or clinically obese!! My waist is 32 inches, and my body fat is 16%. So in actual fact I’m actually a perfectly healthy weight.
This misleading result is mainly because the BMI is a rigid measurement system which does not allow for different body shapes and genetic inheritance. Where the BMI is concerned, proceed with caution.
Diets don't work (DDW) approval rating – 4/10
2 – Waist measurement. Another method of assessing whether you’re a healthy weight is to measure your waist. As a personal trainer this is one of the single most important measurements, especially considering that recent studies show a direct link between fat stored around the middle and internal fat. Internal fat increases your risk of heart disease and diabetes.
Waist measurement, along with the tightness (or otherwise) of your favourite frock/jeans are two of the best guides to your health and size. Use your common sense, and remember that you can be overweight but very fit and healthy through exercise, just as you can be thin, unfit, unhealthy and at risk of many common life-threatening diseases.
DDW approval rating – 8/10
3 – Body fat analysers. These are most commonly modern bathroom scales with metal footpads or hand-held readers with metal grips. These pass a small, safe electrical signal through your body. Lean tissue, such as muscle and blood contain water and act as conductors of an electrical signal, while fat resists it. The greater the resistance, the more body fat you have.
Although these analysers are reasonably accurate they may not give the full picture depending on where the electrical current goes. If you use the handheld model, it will only give you a reading for your upper torso, as the current only goes from one hand to the other.
Likewise, if standing on the scales or a plate, the signal will go up one leg and down the other, so only measuring the lower body. Overall though these are a reasonable guide-if in doubt measure your waist and see how your favourite jeans are fitting.
DDW approval rating – 5/10
4 – Skinfold measurement. The skinfold estimation methods are based on a skinfold test, also known as a pinch test, whereby a pinch of skin is precisely measured by calipers at several standardized points on the body to determine the subcutaneous fat layer thickness. These measurements are converted to an estimated body fat percentage by an equation.
Some formulas require as few as three measurements, others as many as seven. The accuracy of these estimates is more dependent on a person's unique body fat distribution than on the number of sites measured.
As well, it is of utmost importance to test in a precise location with a fixed pressure. Although it may not give an accurate reading of real body fat percentage, it is a reliable measure of body composition change over a period of time, provided the test is carried out by the same person with the same technique.
Skinfold-based body fat estimation is sensitive to the type of caliper used, and technique. This method also only measures one type of fat: subcutaneous adipose tissue (fat under the skin).
Two individuals might have nearly identical measurements at all of the skin fold sites, yet differ greatly in their body fat levels due to differences in other body fat deposits such as visceral adipose tissue (fat in the abdominal cavity). Some models partially address this problem by including age as a variable in the statistics and the resulting formula.
Older individuals are found to have a lower body density for the same skinfold measurement, which is assumed to signify a higher body fat percentage. However, older, highly athletic individuals might not fit this assumption, causing the formulas to underestimate their body density.
DDW approval rating – 9/10 (if done correctly)
Body fat is only one aspect of health. Your GP can advise whether additional measurements such as blood pressure, resting heart rate, blood cholesterol, fat% and glucose tolerance tests are necessary.
If your BMI and waist circumference indicate you're overweight, changes to your lifestyle could help to control your weight. Think about how you can make changes to your diet and physical activity over the long term. Get a Diets Don't Work personal trainer!
Are you a healthy weight but unhappy with your figure?
If your weight lies within the healthy range but you're unhappy with your shape, you'll probably derive more benefits from a supervised exercise programme than by restricting your diet. Quite often we find that clients who have been training with us for a few months may still be the same weight but will have dramatically improved measurements and body shape. They have toned their muscles (not bulked up) and lost fat. This training will improve your fitness, help to tone specific muscle groups and enhance your overall health and well being. At Diets Don't Work all our Personal Trainers in London and the Thames Valley focus both on input (what you eat) and output (exercise) and by addressing both sides of the weight equation get the best results.
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