Let's start off with the term metabolic rate, in this video we are defining metabolic rate as the amount
of calories you would burn off in a day while at rest, so not moving around or being active. In the
fitness community there are two popular formulas to calculate this, BMR, basal metabolic rate, and RMR,
resting metabolic rate. BMR is taken after eight hours of sleep and twelve hours of fasting. RMR
is taken under less restrictions and has been shown to be statistically more accurate. Let's
look at a couple of examples. Here we have Kyle and Samantha, and their metrics are shown here,
Kyle is 44 years old, 5 foot 8, and weighs 160 pounds, Samantha is 33 years old, 5 foot 4, and
weighs 126 pounds. The RMR equation for men is 4.55, times weight in pounds, plus fifteen point
eight eight, times height in inches, minus five, times age, plus five. For women the equation is
four point five five, times weight in pounds, plus fifteen point eight eight, times height in inches,
minus five, times age, minus 161. When we plug in Kyle and Samantha's numbers we see that Kyle's
RMR is fifteen hundred ninety two, point eight four calories per day, and Samantha's is twelve
hundred sixty three, point six two calories per day. So, after rounding up this tells us that if
Kyle and Sam were to sit around all day, they would need 1583, and twelve hundred sixty four
calories per day, to maintain their weights. We know that neither Kyle or Samantha are going to sit
around all day, so, there's a multiplication factor that we must use next, it's based on each of their
lifestyles. The factor is as follows, one point two zero zero for a sedentary lifestyle, one point
three seven five for lightly active lifestyle, one point five five zero for moderately active
lifestyle, one point seven two five for very active lifestyle, and one point nine zero zero
for an extra active lifestyle. Let's say that Kyle is very sedentary, so, if we multiply his RMR by one
point two, we have 1911.6 calories per day. Now Samantha's, in the very active category, so we need
to multiply her RMR by 1.725, and we get twenty one hundred eighty point four
calories per day. So, based on these calculations Kyle can consume nineteen hundred and twelve
calories per day, to maintain his current weight, and Samantha can consume twenty one hundred and
eighty calories per day, to maintain her current weight. Now you can use the RMR equation, and lifestyle
multiplication factor, to calculate your baseline. Drawbacks, a few things I need to mention. First,
this and any other formula used to calculate your metabolic rate, is just an estimate, there
is a margin for error, second, muscle mass is very important. Let's look at Kyle and Jack, who both
weigh the same, however, Jack has much more muscle mass than Kyle. Since muscle burns more calories
than fat, Jack will have a higher metabolic rate, the formula does not account for this situation.