Pf and Pe = Perception of food intake and Perception of exercise

Hunger and the rigors of exercise have an effect on our judgment of eating and physical activities. Only in the last few decades have we had the knowledge to account for all of the energy we store. Before food labels we had only had our hunger to tell us if we were burning more calories then taking in. Even worse, if you are starting to feel hungry it means that your metabolism, the vital component to burning fat is shutting down. Still worse your lack of protein will cause your body to start tearing the proteins it needs from your muscles. So before food labels you would have had no information unless your the sort that could experiment enough to learn what foods to eat and in what quantities.

It also makes sense that when people are asked how many calories they burned after a run they always project higher numbers. Exercising vigorously means you burn lots of calories right? Well we can't say that because the opposite can also be true. Anorexia is in part a problem of perception. First in the perception of what a healthy life style is, but also in that what little food they do eat they overestimate the number of calories consumed and under estimate the number of calories exercised. Lucky for us however we have such great scientific information at our disposal for knowing how many calories we burn doing any exercise.

Your perception of food intake is most likely flawed due to hunger. If you only eat two or three meals a day then your probably over eating, even though you probably feel hungry in the middle of the day. How is this possible? When you don't eat it drives your insulin down. Lack of insulin signals your hunger response, it also signals your muscles and organs to feed less (fewer calories burned), and your fat cells to store more (Gain fat). Now your body is in starvation mode. In starvation mode your hunger will increase as your insulin level decreases. This means that when it comes time for your meal time, you eat and eat and eat. Maybe it's that big plate of spaghetti or that McDonalds Double stack but you need more food to satisfy your hunger. Since your hungry you order the biggie size which brings the total calories to over 1100. Yet still, after your huge meal you'll still feel hungry, because it takes 20-30 minutes for your kidneys to start releasing insulin after cleaning the nutrient rich blood coming from your big mac. After the insulin starts flooding your system you'll get an energy high, you'll feel good, but 2 hours later even though your blood is filled with McDonalds your insulin starts coming down and all of those calories start getting sucked up into your fat cells. It's time to find a way count calories other then hunger.

The first tool I will discuss is calorie counting. I have already discussed how modern nutrition science allows food manufacturers to calculate the calories in their foods and print them on the packages. There are proprietary systems like weight watchers which have created very elaborate schemes based on this information to control food intake. The success of weight watchers is in part due to the fact that no one wants to spend an hour a day looking up the nutrient information in a book. Calorie counting used to be very problematic, one would have to have a dictionary sized book with data on all of the basic foods. The books couldn't hold all of the necessary information and searching through the pages in the book was time consuming. The best solution is to use a website, database program, or some form of metabolism measuring device such as the body bugg.

If you use Linux there is a program called NUT. NUT uses the SR-19 food database published by the US government and is a great system for keeping track of your calorie and nutrition. It has a simple search engine, and lots of data.

A more comprehensive on-line solution exists at www.my-calorie-counter.com This has the advantage that it's database is much more complete and updated more frequently then the SR-19, you can create meals and add new foods that it doesn't have, plus you can log your physical exercise. However, they charge a subscription fee to unlock certain necessary features. I subscribe and feel it's worth it.

The most expensive and fancy way of monitoring your caloric intake and exercise is the body bugg. The gadget keeps track of your total calories burned. This means you always know how many calories you can eat in a day. It can even show you a hourly breakdown of your metabolism using a simple bar graph. You could use the body bugg information to tailor your eating and workouts to burn the most fat.

Exercise is very similar to eating in that we lose sight of the actual caloric value of the work that we do. If someone has just run 6 miles they are likely to over estimate how much food they could eat to make up for the calories lost. Combine that with eating three meals a day and they will almost assurdly eat more then they burned. The opposite can also be true, many dieters completely ignore exercise and try and starve their way to being thin because they see little value in exercise or feel they can't do it. Later we will learn more about why exercise is MORE important then cutting calories in a weight loss program.

Sports medicine has created an important tool for calculating the number of calories burned in a certain exercise. Metabolic Equivalent units or METs is a measurable unit that has come from Sports research. The unit is measured by sampling how much oxygen an individual uses while performing a task such as running. One MET is defined as 3.5 liters of oxygen per kilogram of mass per 60 seconds. The reason this is a good system to remember is because it's universal. A small skinny woman doing a particular exercise has the same number of mets as a large fat man. This means that you can keep track of this simple number while you exercise and leave the complicated calorie counting to your computer at home. The calorie counting website I mentioned will automatically translate your met score into the number of calories burned. It also means that it's easier then some other methods which require you to keep track of your heart rate. It's important to make any exercise you do fun and plentiful, using heart rate measurment you could more accurately identify the number of calories you burn, but it may become tedious and lead to your dropping your fitness goals.