A scale gives you information without context. A scale only provides a number at that specific time, but it doesn't tell you the complete story. Your weight can be affected day to day by many things that are not taken into account on a scale.
What the Scale Doesn't Tell You
Total health
1. A scale only reveals your body weight at a specific time, but not overall health.
2. Your healthy weight depends on diet, lean muscle, daily activity, metabolism, age and genetics, which a scale does not report (or in the case of lean muscle—not accurately).
3. The scale could indicate weight loss or gain, but doesn't tell you if you are underweight or overweight for your height and body composition.
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If you are hydrated or dehydrated...
1. The scale might mislead you to think you have gained weight if you are well-hydrated or lost weight if you are dehydrated.
2. If you experience a 2 percent weight loss post workout, this is not good weight loss because it indicates dehydration and electrolyte loss, which affect your performance.
What or when you ate last...
1. The scale might show weight gain or loss only as a result of how much and what types of foods you ate during that particular day or meal.
2. If you eat foods high in sodium you may retain more water, causing you to have a false weight gain.
3. If you weigh yourself immediately after a meal you might think you have gained weight, but the scale is only reflecting food weight.
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If you have gained or lost muscle...
1. A scale cannot measure changes in your body composition.
2. You might see a false weight gain with increased lean muscle mass or a drop in weight after losing lean muscle mass. This is because muscle tissue weighs more than fat tissue plus muscle losses happen much more quickly and easily (unfortunately) when compared with fat loss.
3. Scales cannot tell you if your body composition is healthy or unhealthy.
How To Use a Scale Effectively
1. Weigh yourself only once a week.
2. Weigh yourself on the same day each week first thing in the morning in as little clothing as possible and after voiding. This will eliminate any inaccuracies due to clothing, food or water.
3. Realize that your weight changes throughout the day, so the number itself will be different depending on what time of day you weigh yourself. Your weight can fluctuate up to 5 to 7 pounds over the course of the day.
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Weight change
1. If weight change is desired, aim for no more than 1 to 2 pounds a week.
2. Weight gains larger than 1 to 2 pounds a week could indicate you are gaining fat tissue instead of muscle tissue.
3. Weight losses larger than 1 to 2 pounds a week could indicate you have lost muscle tissue instead of fat tissue.
Better Methods to Determine Changes in Body Composition and Weight
Skinfold calipers
1. Used to measure body tissues in different places on your body to estimate a total body fat percentage.
2. Have someone trained and experienced take skin fold measurements to ensure accuracy.
Circumference measurements
1. Measures of neck, chest, upper arms, waist, calves and thighs are taken with a special measuring tape. This gives insight into where body composition changes are occurring.
2. Use a Bod Pod, which is a chamber you sit in that measures air displacement. This provides a good measurement of body fat percentage but is usually only available in athletic departments or universities.
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