####################################################################################### ############## To Do ############## ####################################################################################### I would also limit the age range to the young to middle aged adult since resting metabolic rate changes relative to lean mass outside this range. SR - if age is out of range, display a non-disruptive message that says data is not exact for your range Slider text box should display values allowed by the model but out of the range of the slider >>Slider text box values can go outside the slider range >>Looks like wrong behavior for when a user types in an out of range value Buggy behavior when an icon overlaps both the toolbox and the plate (nullpointerexception) Yellow item description overlaps yellow exercise bar chart and obscures changes ####################################################################################### ############## To Do/Noah ############## ####################################################################################### I am not sure that I entirely agree with your calorie expenditures for physical activity. They seem a bit high and in many cases are absolute values. The total caloric cost for weight bearing activities should be based upon a per body weight value. What was your source for this information? SR - We'll choose a function for running, biking, etc. Noah will come up with these functions. Some activities will say “depends on weight” (others will just give a fixed calories value) Height Incorporate growth or height changes with weight? should we increase this? yes, look on web for height changes since BMI =f(height) SR - Problem: Fat % should be based on height and weight and gender, and update whenever height or weight or gender changes. Fat free mass depends on height & gender only, not on weight, thus BMR depends only on height and gender Noah P will provide these functions ####################################################################################### ############## To Discuss ############## ####################################################################################### Balanced diet should readjust when you set your weight (maybe) -kathy said "possibly" BMI: Are we accounting for sex affects on BMI and BMR? NP - There is no “sex affect” on BMI – it is just height/weight^2. NP - BMR should differ by sex. SR – According to Exercise Physiology 4th Ed. By McArdle, Katch & Katch, 1996, p154, the Resting Daily Energy Expenditure is: RDEE (kcal) =370+21.6 * FFM (kg) This equation is said to apply to males and females over a wide range of body weights, and is the equation recommended to us by the CU Integrated Physiologists Can we put a chart or weblink to compare healthy or unhealthy BMI? (see categories chart on national heart lung and blood institute bmi calculator page) NP – there is a useful chart on wikipedia. The problem with this is that BMI is not the only indicator of health. People with high BMI can still be healthy. SR – Are there other factors within this simulation that we should use to indicate health? Or perhaps overall health is not sufficiently covered by this simulation? Or perhaps we should be clear that the indicator is only a measure of BMI. We are still confused about a delay in weight loss if: all variables remained constant: diet and lifestyle and then we ran a mile, why there is a delay in weight loss. NP – this is interesting. I haven’t been following this thread, but I have a theory. It might be because the exercise burns the calories you already ate, so you don’t lose the weight there. You lose the weight when your normal metabolism tries to burn up food, but the food is gone since you already burned it exercising, so then you burn fat. This causes a delay in weight loss (in fact, you gain weight when you eat the food, which you then lose again when you exercise, putting you back to the weight you started at.) I think you should be able to do "step day", so you can see the effects of 1 hour activity. NP – I don’t think this is realistic. People do step on a scale every day, but they don’t realize that the statistical fluctuations in weight (due to the weight of food, water retention, etc.) are probably larger than the amount of weight you can actually lose in a day. Note a lb. of fat is ~3000 calories. So if you weigh 150 lb and you some how burn 1 lb. of fat in a day (unlikely), this is <1% change in weight. Change in intake or expenditure … doesn’t lead to ideal weight loss, since other compartments adjust to compensate Caloric intake changes resting metabolic rate Extra carbs or protein can increase RMR (not agreed upon in scientific community) Is it true that I can eat a hamburger per day above a 'healthy diet', and have a steady weight (though a ~10 lb gain) after about three years? - to see this, click 'reset all', wait until you're 23 years old, then add a hamburger per day. >>The behavior of this has changed since we started keeping BMR constant over weight change >>Is the new behavior acceptable? 3000 kcal/day wrong, should be 2000kcal/day should this be exact? can't force 2000kcal/day and prescribed ffm and have balanced calories As I add the exercise the graphs begin to change, but I can't see whats happening from the getgo because it runs while the exercise window is open. I think this might make it difficult to understand what the starting point is and what the added exercise is changing. >>To address this problem, I started the simulation paused; hopefully the user will be able to pause the simulation before >>adding exercise/diet. If not, we can either pause the sim when they bring up an editor, or add a control to the >>diet selection panel >>Now that the simulation has drag-and-drop for editing diet and exercise, perhaps it should start running? >>Or perhaps the sim should start running as soon as the first item is dropped? >>Or perhaps a wiggle me should be used instead Satisfy learning goal: How long do you have to bike/walk to burn a certain number of calories? the learning goal seems too easy: to figure out "How long do you have to bike/walk to burn a certain number of calories?", you just have to look at the number of kcal/day in the text of the exercise type. might be better to ask how long it would take to lose 10 lbs? How is body fat calculated? How would a student know their % body fat to put in the simulation? NP – most people don’t know this. It is done either with a skin fold test (calipers), electric current (this is how these scales do it, not entirely accurate), or a submersion in water test (need a special facility). With skin fold, all the numbers are entered in a spreadsheet and it spits out a %. Electronic scales use weight, height, and conductivity (I don’t know the equation. I know it depends on how hydrated you are, and how long your legs are.) Better values/more options for base diets Need more junk food for diet options, like actual student diets: burrito, chips, cookies, tacos, sub sandwich, twizzlers or candies, etc When I was trying to learn about BMI, body fat and heart health I found that we should be able to address a lot of the factors that are used to determine heart health. Especially if we are including BMI since it’s typically associated with that. I think it’d be a really nice addition if we could add this as a learning goal. We could have the little question mark by the heart pop up a window with the list of risk factors for the heart from the American Heart Association. This I think is also useful to do because it will give a person a better idea of the value of BMI. As it is now, it appears that BMI is more of a stand alone indicator of health which it definitely is not. I’d like to see us make this sim a resource that offers more than the typical text book or activity can. So I was hoping to expand a bit into some of these things that are closely related and can easily be integrated into the sim. Clarify the meaning of "lifestyle" vs. other daily exercises Add description to sedentary, moderate activity, etc. >>I removed the Athletic Lifestyle option, do I need to add tooltips to explain other lifestyles? ###################################### # Edit Diet ################### Add a legend for caloric breakdown pie chart Number of calories of healthy diet should be editable Add/Remove items from Edit Diet should be synchronized with Plate graphics I wanted to click on the food item or description rather than the add button. Can you change the interface to something like that. That would clean up this box a bit as well. Add a done button at the top of the diet and exercise boxes. Editors for exercise (change time or intensity) Would it be informative for students to see what 590kcals/day is equivalent to (for example 1 hour of swimming, or 2 hours of pilates?) NP – possibly – or have them figure this out on their own might be better. The energy cost of walking/running is about 1.43 kcal/kg/mile, swimming 4x higher, biking 1/4 value of walking NP – this is probably not the best way to represent this. It should probabaly be kcal burned per hour rather than per mile. It may be that biking is ¼ per mile, but you travel at least 4x as far on a bike in the same time. In fact, because of wind drag at higher speeds and the ability to climb hills very quickly, the actual “work” done cycling can be considerably higher than other activities. ###################################### # Fat % issue ################### I'm having trouble making sense out of this. It appears that if I add weight my BMR increases tremendously. I thought BMR does not increase unless muscle mass increases. Then I see that adding to my weight does not change my body fat. That seems very strange to me. Shouldn't that be a calculation of my weight and height with a slight scaling due to the muscular slider? The way it's set up, adding to a person's weight immediately causes calorie burn to compensate and they get lose weight immediately. This does not match my understanding. Weight gain should go into fat% to keep BMR basically constant. My biggest concern is the body fat indicator not changing as your guy gets fatter or you set his weight really high. I agree with Wendy that it doesn't make much sense to not have the percentage fat linked up at all to the weight. Description Women Men Essential fat 12–15% 2–5% Athletes 16–20% 6–13% Fitness 21–24% 14–17% Acceptable 25–31% 18–25% Obese 32%+ 25%+ source: http://en.wikipedia.org/wiki/Body_fat_percentage When you get up to 300+ pounds and have a BMI over 30, you should be into the obese fat percentages, but as lower weights, your percentage should be more in the fit ranges. (The default 26% is quite high for a male so should change if you hit male instead of female.) It seems like when you increase the weight we should also increase the calories in the base diet because otherwise the 300 lb guy loses weight very fast ... normally a guy like that would eat a lot more to maintain his weight. Basically this would be his BMR plus Lifestyle calories. Then be able to add OR subtract from that base diet. This would get away from the unrealistic rapid weight loss by a very overweight person. I found this page somewhat helpful in thinking about the above. http://weightloss.about.com/od/eatsmart/a/blcalintake.htm 1. Percent body fat should change as body weight changes. This change probably be based upon the concept that one pound of fat gain/loss requires a gain/loss of about 3500 calories. It should be noted that weight loss by diet only, results in a loss of both fat (75%) and lean tissue (25%) whereas weight loss via diet and exercise results in a maintenance of lean tissue and a loss of only fat. Food composition should lead to a change in the Fat Free Mass % check with fran, bill & kate regarding change in % fat http://sportsmedicine.about.com/od/fitnessevalandassessment/a/Body_Fat_Comp.htm Can I Change My Body Composition? Yes. To increase or decrease your percent of body fat you need to create the right balance between the calories in and calories out. The best way to do this is to decrease daily calories by about 500 and increase your exercise. Aerobic exercise along with strength training is ideal. If you are beginning a new exercise program, you are advised to first consult your physician. KG gained per day should be a function of caloric distribution over lipids, carbs and protein Performance: consider profiling or changing clock rate >>How severe is this problem? Some exercise and food items are missing icons >>Should this taks be reassigned? Time readouts should be Years:Months, not years in decimal >>What's the best input user interface for this? Need a way to get rid of or clean up icons >>Dragging back to the toolbox removes the item >>Could add a trash can as well Franny said on 6/13/2008: I have been playing with the Simulation this morning and had a question for you. If in this simulation it appears that the change in percent body fat is at a high rate when making even the smallest change. I had a diet that I let run for a few years that was 50 cal above my energy expenditure and i watched my % fat go up by about 15% in a few years and then when I added a walking exercise (one of the lowest calorie expenditures) in a matter of 1 year I went from 30% body fat to about 10% body fat. I was wondering if there was a way to slow down the change in % body fat. i am not sure if it is equation based and has a time function built in, but that portion is not very realistic, so i thought i'd point it out. Noah said on 6-13-2008: -------- Here is something I came up with for controlling height, weight, and % fat. Let me know if you think this is a good solution. I'm just emailing you all instead of adding it to the to do yet because it is a long description of my reasoning (and I don't know yet that this is what we want to do.) An average healthy BMI is about 21. BMI = mass/height2 (kg/m2 ) The range is about 18.5-25. Take this to figure out the average lean body mass (LBM, or fat free mass FFM) for an individual of height h. So what does this mean for an average person 5’8” (1.72 m)? m = BMI*h2 = 18.5*1.722 = 54.7 kg (120.6 lb) 21*1.722 = 62.1 (136.9 lb) 25*1.722 = 74.0 kg (163.1 lb) 30.6*1.722 = 90.5 kg (200 lb) Arnold Schwarzenegger had a BMI of 107 kg / (1.87 m)2 = 30.6. For our 1.72 m dude, Arnold's BMI would give a mass of 90.5 kg (200 lb). Lance Armstrong has a BMI of 74 kg / (1.77 m)2 = 23.6. So, even a thin but very fit individual is nearing the upper range of “healthy” BMI. Note this is a HUGE range of BMI, and all of these individuals could have %fat < 10%, making the LBM 108-180 lb. Here is what I propose: There should be a range of allowed LBMs for a given height. Define a “Lean Body Mass Index” = LBMI = LBM/height2 . Let’s assume the ends of the BMI scale above are for 10% fat. So the LBM for a 1.72 m male is 50-82 kg. This makes our LBMI range 16.65-27.6. This range of LBMI will be a set limit in the sim code. If you set a certain height, anything above the maximum (27.6) MUST be fat. You will have free and independent control of height, weight, and % fat, constrained by these limits. So you can make a lean, very muscular person who has a very high BMI and is still healthy because their % fat is low. Functionally, if you set a certain height, then when you change weight within the LBMI limits, % fat does not change. If you go outside of the LBMI limits, the % fat slider will automatically change to compensate. As far as readout for this stuff - 1st pass could be charts of LBM and fat mass. 2nd thing, more complex, could be to somehow show muscles shrinking and growing inside a layer of fat in the picture of the person. I'm still thinking about how this could be done. -Noah P. -------- ############################################################################################## # Health Indicators # ############################################################################################## I’ve been researching BMI and body fat today and have a few recommendations. I need to look more to finish this up but this is a start. BMI is weight/height^2 which it seems you have wired in already. This was developed in the late 1800’s and never meant to be used as it is today. It’s simply a statistical pointer for sedentary people. It was never intended for use on individuals or as a predictor of health. It’s a poor indicator for taller people and the ranges for Asians is different since they have a clearly different build. Also the calculation and the ranges that are considered healthy do not have any differentiation for men and women. This makes no sense since healthy body fat levels are very different for men and women. In any case, 19-25 is good, below 19 is underweight, below 16 is starving, over 25 is over weight and obese is over 30. IF we decide to have the heart tied to BMI this is how I’d do it. I would have the heart have no smile or frown for underweight and overweight and a frown for starving and obese. I’m nervous using this however, since I found studies that showed things like 61% of people who had normal BMIs were actually obese when body fat was measured and that athletes or tall people will look overweight or obese according to their BMI. Lance Armstrong’s BMI said he was very overweight when he competed in the Tour de France. So I vote for showing BMI but not having it tie to the heart. Body fat is a better indicator of that. The American Heart association uses BMI, with waste measurement and number of health risks from a table of 8 things like do you smoke, high LDL, low HDL, high triglycerides etc… It could be one of the learning goals to see that BMI does not change with %body fat, sex, or age. Maybe for our real thing button we could give some information from these other sites on risk factors etc… I can put that together if we decide to do that. For this sim I think the heart smiling should be a function of body fat, sex and age. Body fat is more complicated. It definitely needs to go above 40%. It’s hard to figure out for sure since obesity is now determined by BMI and not body fat, but a lot of studies do use this. So it appears that 32% of the population has body fat over 35%. So 40% is definitely a low limit. I’d allow at least 75 or 80%. I figured this thinking about a 5’4” woman who started at 348 and lost 200 lbs. This was on the weight watchers site. She was very heavy at 348 but did look like someone you’d see if you went shopping for example. I did some quick calculations and assuming she was sedentary, she probably had body fat just over 70%. I need to do some more looking and we need to consider the interaction between the body fat slider and the other controls as well as the learning goals. If we are interested in health, then its’ important to note that waste circumference and body fat are both much better indicators of health than BMI. I also think we should rethink the shape of the person and how they look as they gain weight. Its’ very different for men and women and this is an important aspect of health so might be worth considering. In the long run, the body fat slider should be tied to the exercise/lifestyle as well as the weight. I found studies that showed people losing weight and increasing their body fat because they were too sedentary. Once we know exactly where we want to go with this, I’ll find the info we need to model it appropriately. I wonder if, before putting more time into this, it might make sense to check with some potential teacher users. If they all just use BMI, and are not aware of and/or want to teach any of these other more complicated things, it is not going to improve sim by putting them in. Teachers will just either assume sim is wrong, or decide not to use it because it will confuse the kids. I assume this asking a few other teachers who are potential users is something Ingrid could do fairly easily. All the statistics for the country on obesity use BMI; however, any federal agency or some of the medical help sites on health risks print the exact warnings about BMI that I’ve mentioned here. That’s why I wanted to include them in the sim. I didn’t have to look in some obscure place. So I think it’d be good to have in the sim even if teachers do just use BMI because we could have a little info button (like our see real laser button) that has the exact wording from one of the federal sites. This way we are educating the teachers as well and in a way that would probably not get them to think the sim is wrong. Ok, as long as it is set up so you can have it both ways.