You've got around 650 muscles in your body, and they make up roughly half of your bodyweight. These muscles can be divided into three different groups: skeletal, smooth and cardiac. All of these muscles can stretch and contract, but they perform very different functions.
Skeletal muscle: Produces movement, maintains posture, stabilizes joints and generates heat
Smooth muscle: Found in the walls of hollow organs
Cardiac muscle: Exists only in your heart
Skeletal muscle: The tissue most commonly thought of as muscle is skeletal muscle. Skeletal muscles cover your skeleton, giving your body its shape. They are attached to your skeleton by strong, springy tendons or are directly connected to rough patches of bone. Skeletal muscles are under voluntary control, which means you consciously control what they do. Just about all body movement, from walking to nodding your head, is caused by skeletal muscle contraction. Your skeletal muscles function almost continuously to maintain your posture, making one tiny adjustment after another to keep your body upright. Skeletal muscle is also important for holding your bones in the correct position and prevents your joints from dislocating. Some skeletal muscles in your face are directly attached to your skin. The slightest contraction of one of these muscles changes your facial expression. Skeletal muscle generates heat as a by-product of muscle activity. This heat is vital for maintaining your normal body temperature.
Skeletal muscle represents approximately 30% of body weight of a healthy 58kg woman or 40% of a 70kg man.

This is important for monitoring and maintaining healthy bones through exercise and calcium-rich diet.
An adult skeleton is made up of 206 bones, which come in several different shapes and sizes and have specific structure.
Your bones contain blood vessels, nerve cells and living bones cells known as osteocytes. These are held together by a framework of hard, non-living material containing calcium and phosphorous. A thin membrane called the periosteum covers the surface of your bones.
Bone Mineral Content differs according to age and sex.

Body fat scales give a more detailed picture of your body composition than simple weighing scales. They let you know if your body weight is made up of lean muscle or of fat. They allow you to understand whether your diet or sports routine is leading to a loss of water or if you are actually burning fat? (High levels of body fat are a contributing cause of many serious illnesses, including heart-disease, diabetes, and certain cancers.)

The 2 main reasons for keeping track of your body water levels are: 1) To find out if you are sufficiently "hydrated" - your body needs a certain percentage of water to function properly (heat regulation, bringing nutrients to cells, cushioning vital organs, etc) - see instructions for more info.
2) To differentiate loss of water from loss of fat while dieting.

We recommend always using the same scales in the same conditions, once or twice a week. Measure yourself in the morning, preferably naked, when you are rested, not dehydrated and you have been to the bathroom.

Body fat and Body water results are indicated as a percentage of total body weight. A results evaluation bar on indicates where the user's body fat level is situated compared to the medically recommended values. (A reasonable range of percentage body fat for the adult male is between 14 and 26%; that for the adult female is between 20 and 33%.)

In certain cases, the method of body fat measurement that we use (BIA method) can overestimate body fat in adult, elite athletes. This is due to physiological differences, such as muscle density.
If you are over 18, have been consistently training at least 3 times a week for at least 2 hours each time for a long period in a sport which involves a sustained cardio-vascular effort, then use the athlete mode for optimum accuracy.

Every weighing scales is calibrated differently and there can be small differences between the results on 2 different products. However, if these variations are under 2kg, then the product is not defective. The important thing is always to weigh oneself on the same scales, in the same conditions, once or twice a week, in order to track long-term changes.

The more precise a weighing scales is, the more sensitive it is. You must always place your scales on a hard and flat surface. During the measurement, try to stay as still as possible. It is perfectly normal to have differences up to 500g between two measurements - this can be explained simply by standing differently on the product. Again, the important thing is to measure long-term variations and not the difference between two measurements.

As for weight measurement, body fat or body water results can vary without the product being defective. In fact the scales is performing a very complex calculation based on several variables - if any of these changes, then the results can differ:
- A common reason for variation in body fat is variation in body water levels. These can vary hugely depending on the time of day, on whether you have been to the bathroom and at different stages throughout the menstrual cycle.
- If there is a variation in body weight (such as wearing more or less clothing) this can affect the results of body fat/water measurement.
- Even standing on the scales differently can cause minor variations.
Remember: we are estimating body fat and body water levels so that you can track the changes over the long-term. Also, our scales show a body fat/water results as a percentage of total weight - it is therefore possible to lose weight while increasing body fat percentage (losing water or muscle).

You cannot use a body fat product - as a general rule you should avoid all sources of electronic interference.

We do not recommend that you use this product. The results will be highly falsified because pregnancy changes the water levels in your body (we measure body water in measuring body fat). If you have used the product, there is no need to worry but avoid using it again until after the birth. You can however use the weight-only feature of your product by stepping directly onto the platform.

If your coil contains copper, then it's possible that the result will be slightly falsified because the copper will effect the measurement. However, there is absolutely NO RISK to the effectiveness of the contraceptive or to your health.

This means that the scales is not properly set or "initialized": Remove the battery and reconnect it. Then tap lightly on the scales when the display is off - it will start up and then switch off. Now step directly on the scales and stay still. Your weight should be displayed. Now you can use the body fat function by pressing ON or MODE.

This means that the weight was not stable. Make sure to stay perfectly still during measurement.

This means "overload" - is it possible that the weight applied is over the maximum capacity (140kg or 150kg depending on the model)?

"Body fat reading is not possible". Have all labels been removed from the product? Are you in bare feet? For certain users, it may be necessary to dampen slightly the soles of the feet to allow the current to pass more freely.

"Percentage of body fat is under 5% or over 50%". Have all labels been removed from the product? Are you in bare feet? For certain users, it may be necessary to dampen slightly the soles of the feet to allow the current to pass more freely and get most accurate results.

"Body water reading is not possible". Have all labels been removed from the product? Are you in bare feet? For certain users, it may be necessary to dampen slightly the soles of the feet to allow the current to pass more freely.