BODY FAT: Define it. Measure it. Lose it.

Think of Body Fat as Your Body's Way of Storing Extra Energy (Calories) and Protecting Itself

The scientific term for fat is adipose tissue, your body stores extra energy in the form of fat cells in the adipose tissue.

MYTH: When you exercise your body turns fat into muscle, when you stop exercising, it turns back to fat.

FACT: Fat and Muscle are separate and distinct. When you exercise you may lose fat and gain muscle, and when you stop you may lose muscle and gain fat. They don't transform into eachother.

Some of your body fat is called essential fat because it provides insulation and protects vital organs. Men need at least 2-4% and women need 10-12%. The remainder is called storage fat, and that's what send many of you to the gym. Body fat tends to increase with age.


Body Fat: Let's Not Get Carried Away with the Measurements!

Body Builders and certain competitive athletes may need to obsess about their % body fat, but most of us just need a simple reliable measurement of progress. There are more than a dozen different techniques for estimating body fat, including infrared and x-ray techniques, and one that involves drinking a radioactive isotope . Keep in mind that any approach gives you an estimate based on various measurements and mathematical formulas, you can't directly measure the fat like you can with weight and height. You would have to go through the inconvenience and mess of removing all the fat from the body, weighing it and replacing it to do that. It is best to look at the body fat measurement over time to see changes, and to have it performed by the same competent person using the same equipment. All of the methods have strengths and weaknesses, and research has been conducted to validate them. Here is a recap of the measurement methods:

Hydrostatic Testing - Immersion in a tank of water and measuring displacement is accurate within about 2% for most people. Adjustments by race are made, since African Americans tend to have denser bones while Asians have lighter bones. Air Displacement Plethysmography (The Bod Pod) is a similar but uses air displacement instead of water.
Skin Fold/Caliper Testing - Results are accurate within +/-3.5% for 90% of the population. Results for the other 10% can be off by much more. Variation by tester can be a big factor, so have the same person take the measurements and look for a trend in the results. This technique tends to overestimate body fat for lean individuals and underestimate for obese. Caliper testing needs to be done slowly, carefully and precisely, usually measurements are taken at least three times and averaged for a result.
Bioelectric Impedance - Results are accurate within +/-3% for 82% of the population, and can be off by up to 20% or more for the remaining 18%. Results are inaccurate for small changes and can be affected by hydration, skin temperature, exercise within 12 hours prior, alcohol within 48 hours, food within 4 hours, bladder and bowel content. A body scale once estimated me at 38%, almost 3x the measurement obtained from calipers around the same time.
Circumference Testing - using a few simple measurements, results are accurate within +/-5% for 86% of the population. (There is an online tester available at bodyfat.caryraffle.com, it measured me at almost the same as the calipers and is very easy to use so that you can track your results.)
Ask me - I can usually estimate someone's body fat within a couple of percent, not much less accurate than some of these techniques and a whole lot easier. (Be forewarned, you may have to show me your bare midriff!). If you get a body fat estimate that doesn't make sense - maybe from one of those diet supplement people who set up tables on the streets or at the mall - feel free to contact me for a second opinion.

Losing Body Fat

There are only 2 proven ways to lose body fat: Burn more calories than you consume or consume fewer calories than you burn. Most of use a combination of both - exercise and watching our diets. What about watching carbs? Sure, if you load up on empty calories your body may crave more nutrition and you'll end up eating more, but protein shakes are also loaded with calories that you may not need. I've got some tips, by no means a complete list but just my personal top 10:

Cary's Top 10 Fat Burning Tips
1. Eat a good breakfast. Numerous studies have shown that people who eat breakfast do a better job losing weight and keeping it off. Breakfast skippers tend to make up lost calories later in the day. They don't have the energy to work out as hard, and the body doesn't produce the enzymes need to burn fat during their workout. One theory is that if you workout hard on an empty stomach, the body goes into "survival mode" - sparing fat and burning muscle protein for energy.
2. Use a combination of cardiovascular and strength training activities. Both burn calories while you are working out. Strength training has the added advantage of building muscle mass so that your metabolism increases - so you burn more calories at rest. Start with a cardio warm up, but avoid long cardio sessions before your strength training if you want to burn fat. You want as much energy as possible available for the strength training session. (If you're already lean and training for a marathon, you can skip this advice). Exercise at least 150 minutes er week, more to make real changes in body composition.
3. Work in the "cardio training zone" and you'll burn more fat than in the "fat burning zone." The fat burning zone is a myth: you may get a higher percentage of calories but the total calories burned is lower. You actually burn the highest percentage of calories while sleeping, not exactly a fat burning activity. The cardio zone begins at about 70% of your maximum heart rate. People who aren't on medication can use 220-age to get their maximum hear rate. (In my fitness orientations, we use a different formula that is more personalized.)
4. Interval training for your cardio activities can increase your calorie burn for several hours after you are done exercising. This is recommended for those of you who have already established an aerobic base. Try alternating between 65%-75% of your maximum heart rate for 2 minute intervals.
5. Circuit Training for your strength activities keeps the calories burning - The idea is to keep your heart rate up by eliminating the rest in between sets. Most of my workouts are organized in compound sets, working opposite body parts so that while one side works the other side rests. You may need to rethink or reorganize your traditional split routines. Just be sure to rest each muscle group for 48 hours in between workouts.
6. Gear your strength training to building lean muscle and burning fat. Target the large muscle groups, your legs, back and chest muscles burn more calories than arms and shoulders, and the latter get worked along with the big muscles. You should generally be working in the endurance strength training zone, so do 2-3 sets of 12-20 repetitions of the exercises at moderate weight. Exercises that require you to stand and/or stabilize generally burn more calories than seated or lying exercises. Total body exercises (i.e. lunges with chest press/lat pull down/biceps curls) really turn up the heat.

7. Don't rely on fad diets and supplements. Try to make lasting changes in your diet and lifestyle. Be careful of supplements containing large amounts of stimulants like caffeine and guarana, these can increase your heart rate and you may already be consuming caffeine in your coffee or tea. Caffeine in moderation does help burn fat. If you're already getting enough protein in your diet, ship the protein supplement you don't need the extra calories! The American College of Sports Medicine recommends that endurance trained athletes consume 1.2-1.4 grams of protein per kilogram of body weight daily.
8. Periodize, or change your exercise routine, at least every 4-6 weeks. Your body adapts during this period and you will see diminishing returns on the time you invest. You can change the pace and duration of your cardio routine. For strength training, change the sets, repetitions, tempo, try less stable exercises and total body exercises.
9. Avoid Overtraining - Muscles grow while you rest. If you are spending more than an hour 3-4x a week working out and not seeing results, and often feel tired and sore, you may be overtraining. Your body shuts down the muscle building process and stops burning stored fat. Work hard, but also rest.
10. Pay careful attention to posture, aches, pains and injuries. You're in this for the long haul and cannot afford to be sidelined by pain or injury that keeps you from working out. It is important to incorporate corrective exercises into your program - call it "prehab" - and avoid exercises that can exacerbate your problem areas. The most common problems that I see include: a. Feet Turn Out /Knees Turn in - sets you up for foot pain (plantar fascitis), knee or hip pain or injury, back pain; b. Shoulders Roll Inward - sets you up for rotator cuff injury, possible upper spinal injury; c. Arched Back - Sets up disk injury may also indicate predisposition to abdominal herniation. I am happy to meet with you, assess you for these potential issues and discuss appropriate corrective exercises and program modifications.

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