this mini lecture is an excerpt from your chapter 8 lecture that's coming up a little later but we're just lecturing on these few slides out of Chapter eight so that you can finish your homework for this week which is your anthropometric worksheet if you haven't already watched my 10 minute tutorial please go back and do that first that will help you get started on filling in the height and weight blanks that you'll see on the far left of the anthropometric worksheet so again this entire mini lecture is just so that you can fill out that worksheet so you really want to have that available if it's too difficult for you to type in your answers and calculations into that worksheet feel free this is one of the few exceptions that I would say you can print it out right on it and then take a picture of the front and back if that's easier for you otherwise have the document pulled up so you can fill it in as we go so I'm going to assume that you have the height and weight already filled in because you watched the tutorial if you need help please go back and look at that next we're going to fill in the body mass index first we need to learn what that is we had a biostatistician a couple of decades ago gather all this data about how early people died and how much disease they had compared to their height and weight so he compiled all this data and found that wow if you weigh too little you die early of a lot of disease if you weigh too much you die early of a lot of disease so he developed this equation that we now call the body mass index Mass just being your weight and it will tell you one of the data points that you can learn about yourself it's an anthropometric data point to find out about how healthy or unhealthy you are it's just one of many data points we're going to collect today it's just going to help us build a picture of Who You Are if you are accustomed to using the metric system go ahead and take out your calculator and punch in your weight in kilograms and divide it by your height in meters squared if you have a really simple calculator you might want to do meters squared first meters squared is just your height in meters multiplied by your height in meters jot that number down somewhere clear out your calculator and then hit kilograms divided by that number if you're going to do the American system with me then go ahead and pull out your calculator and I'm going to walk you through the steps and at any time if you need to pause the video go ahead and do that and Rewind it but I've done this about 277 times probably more than that so this is the way I've always done it okay take out your calculator and first of all punch in your height in inches now hit multiply and punch in your height in inches again and hit equals this is probably a four digit number jot that down somewhere and clear out your calculator now punch in your height in pounds hit divide and enter in that four digit number that you found that was your height in inches squared and hit equal and this is a very scary looking long decimal number right don't do anything except press multiply 703 equals okay that is your BMI and you can just give me it to the nearest tenths place so give me the first two numbers ahead of the decimal point give me a decimal point and then give me the first number after that so it should probably probably for most of you is going to be in the 20s if you get something in the 50s or the hundreds or uh just a decimal long decimal you did it wrong go back rewind try it again I do need to see your calculation work on that worksheet so if you need to rewind this that's totally fine or if some doing this some other way makes more sense to you that's fine too but that's the way I've always done it in clinical setting all right what are the problems with that so I'm about to show you a graph that's going to say basically how long are you going to live and how healthy are you going to be and it's based on the BMI does anyone have any problems with me telling you you're going to die early of a lot of disease or not just knowing your BMI the BMI is pretty limited right I don't know how much you exercise based on your kilograms in meters right I don't know how much alcohol you drink or if you smoke meth or if you have an eating disorder all I know is your height and weight okay a lot of people will also say well I'm just super muscularly super muscular or I'm big boned that's why my BMI is high for most of us the BMI works just fine but there are some exceptions we'll talk about here in a second all right moving on to the BMI classification you need to circle on your worksheet whether you are underweight if you're 18.5 if you're less than 18.5 Circle underweight on your worksheet if you're between 18.5 and 24.9 see this is all written down here Circle healthy weight notice we did not use the word normal circle the word healthy if that's you if you're 25.0 to 29.9 circle the word overweight if you're more than 30 circle the word obese and just for your reference morbid obesity comes in at 40 a BMI of 40. okay like I said this will work out just fine for most of you but what if you're like hey this says I'm overweight and my body fat is terrific or my mom said I have big bones what about that let's look at a few people and put them up here Michael Phelps is a BMI of 23.2 Michael Phelps is an Olympic swimmer very lean um and so oftentimes people say well I have a lot of muscle so my BMI is high well Michael Phelps arguably has more muscle than all of us so but his BMI is healthy I've got a couple more Usain Bolt he's right on the borderline he's just a a point a tenth of a decimal away from being classified as overweight if you don't know who Usain Bolt is he is a sprinter and you know those guys are very slim and he's won a ton of Olympic medals so obviously he's in terrific shape but you can see that is his height for weight puts him right here so he's very muscly for his height let's take a look at this next guy LeBron James a Laker I hope that's right I think he's a Laker he gets the overweight category 27.5 Google a picture of him if you don't know who this guy is very lean and not overweight at all so BMI doesn't work for him this is Prince Fielder I showed you guys a picture of this guy when we were talking about vegetarians and he doesn't look very trim um I will say that but he does make his living as an athlete so I don't know his body fat percentage though that would be helpful okay I think that's all um but it is interesting to see that it works for most of us but there will be those people that are the outliers statistically I used to do more celebrities and a lot of the celebrity males um back when Tom Cruise was a little less hateable I put him up here and he was in the overweight category things like that okay so we don't want your BMI to be too low or else you're going to die early of a lot of disease mortality or we don't want your BMI to be too high or else you die early of a lot of disease so we want this nice little sweet spot okay so based on your classification of your BMI you now know that answer but wait there's more right that's just one data point let's add more data points to your picture