Body Mass Index (BMI)
Body mass index is a measure used to determine whether a person is of a healthy weight. It is calculated by dividing a person’s weight in kilograms by their height in metres squared. It does not take an individual’s muscle mass into account but will fluctuate as an individual’s weight changes. The FitQuest dial for BMI will fluctuate between red, amber and green with green denoting a healthy weight progressing to red at the extremities of the scale.
Classifications according to the World Health Organisation are as follows:
Severe thinness <16
Moderate thinness 16 – 16.99
Mild thinness 17 – 18.49
Healthy weight 18.5 – 24.99
Overweight 25 – 29.99
Obese class I 30 – 34.99
Obese class II 35 – 39.99
Obese class III ³ 40
Metabolic age is calculated by comparing your metabolic rate to average metabolic rates found across the population.
Basal Metabolic Rate (BMR)
BMR is the minimum energy level a body needs at rest in order to maintain normal bodily functions. During activity, skeletal muscle utilises more energy and a greater number of calories are burned. Your BMR is impacted by the quantity of muscle mass a person has. Increasing your muscle mass increases your BMR, and the number of calories used at rest making it easier to decrease body fat.
The default display is in kilocalories (kCal).
Body Fat Percentage
Body fat percentage shows the amount of body fat as a proportion of body weight.
Body fat is essential to normal bodily function including maintaining body temperature, protecting internal organs and storing vitamins. Excess body fat and visceral fat levels can increase your risk of some medical conditions including, high blood pressure, heart disease, type 2 diabetes, strokes and certain cancers.
The FitQuest dial for fat mass and percentage works through red, amber and green based on healthy percentages as determined by data based on the user’s age, height and gender. For fat, red is used for subjects at either end of the spectrum (i.e. for both underweight and overweight scenarios).
Muscle tissue requires more energy both at rest and during exercise than fat, as muscle mass increases, so does an individual’s basal metabolic rate (BMR).
Muscle mass percentage shows your muscle mass as a percentage of total body weight. This figure is useful for demonstrating whether a user needs to improve muscle mass or decrease fat mass. A supposedly “overweight” user may have a high muscle percentage which may suggest weight loss is not the optimum goal. Alternatively they may have a low muscle mass which suggests that they need to increase mauscle mass as well as reduce fat mass.
The FitQuest dial works through red, amber and green based on healthy percentages as determined by data based on the user’s age, height and gender.
Segmental Muscle Analysis
Segmental muscle analysis provides a breakdown into 5 body parts – core and abdominal area, each arm and each leg. This helps to identify muscle imbalances to help focus a user’s training. This section shows the muscle mass as well as percentage breakdown by area. The muscle mass figure includes the water within the muscle.
The default display for muscle mass is kg.
BIA devices are able to determine the impedance of the signal through the body and therefore estimate the subject’s total body water (TBW). The total body water analysis demonstrates overall hydration level, body water percentage and intracellular/extracellular ratio. Total body water fluctuates throughout the day and night. A person’s hydration level is affected by climate, activity level, illness, menstruation, food and drink consumption.
Body water percentage is the total amount of fluid in a person’s body as a percentage of their total weight. Users should be looking to maintain a consistent total body water percentage within a healthy range. By weight, the average human adult male is approximately 60% water and the average adult female is approximately 50%. In a large study of adults of all ages and both sexes, the figure for water fraction by weight was found to be 58 ±8% water for males and 48 ±6% for females12.
The FitQuest dial for total body water is coloured green to red based on the users hydration status.
The total body water percentage is interrelated to the percentage of body fat and may therefore be slightly skewed for both obese and athletic subjects.
The intracellular/extracellular water ratio:
Intracellular water (ICW) represents water within the body’s cells, whereas extracellular water is the water surrounding the cell.
The ideal ratio is 40% ECW: 60% ICW
The European Food Safety Authority dietary reference values (2010) recommend that adult females should consume 2000ml/day and adult males should consume 2500ml/day. If ICW is lower than ideal, this may indicate dehydration implying users should increase their water intake.