Your basal metabolic rate (BMR) is a measure of the rate of energy (calories) your body burns over a 24 hour period. Naturally skinny people tend to have a naturally high BMR, meaning that they burn off the calories in their food very rapidly by converting the food in to energy and their body then seamlessly turns to body fat to keep them going if the food energy gets low.
There are some genetics involved in this, but there are also many lifestyle factors that can influence whether we are a high, fast burner of calories and fat, or a slow burner and good storer. One of the key principles of BMR is how much muscle you have. Muscle fibres are very metabolically active, requiring a constant supply of fuel, even when we are not actually moving the muscles. Increasing muscle density is what to focus on. Many women are concerned that doing some weights / resistance training will make them bulk up. The reality is, very few women will develop big muscles as testosterone, a hormone far greater in men than women, but essential to women?s health, is at a level for most women equivalent to that of an 8 year old boy. This means bulking up just isn?t going to happen. By challenging your muscles to the point of fatigue, using high weights and low reps, your muscle fibres will increase activity and density, resulting in that higher metabolic burn every second of every day while also giving your body tone and shape, not bulk.
Aerobic exercise, although supporting many areas of health including significant mental health benefits, is NOT an effective means to burning body fat and building muscle. This is such a common mistake made by those who want to slim down. Eating less and exercising more is the opposite of what is required to rev up your metabolic burn.
To really understand why this is the case and discover 3 further, really influential health practices that super-charge the metabolism, read my new book, out on Nov 10th: ?Why Eating Less & Exercising More Makes you Fat?.