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Calories In/Calories Out & the Aerobic Exercise: Two Flawed Theories for Weight Loss

Problems with the Calories In/Calories Out Theory for Weight Loss

The calories in/calories out theory is based on the idea that if one burns off more calories through activity then they consume in their diet, then there will be a net loss in energy, resulting in weight loss. Conversely, if more calories are consumed than burned off, then there is a surplus of energy resulting in weight gain.

The problem with this theory is that not all calories are created equal and are metabolized differently depending on their chemical make-up. Similarly, not all forms of exercise are metabolically equal.

If above diet and exercise recommendation were effective, then 34% of Americans who have been told to lose weight following these guidelines would not be obese.


This theory is based in the first law of thermodynamics, which states "energy can neither be created nor destroyed, but is transformed from one form to another". The problem with this, is that there is a second law of thermodynamics, which takes into consideration the energy lost due to biochemical processing e.g. digestion, the nature of the fuel and other processes involved.

The second law of thermodynamics helps to explain the metabolic advantage of low-carbohydrate diets that equates to greater weight loss as compared to "isocaloric" diets (i.e. diets containing the same amount of calories, but apportioned differently e.g. low fat/high carbohydrate).

High carbohydrate diets generally promote an over consumption of cereals, grains, legumes and fruits. These foods tend to have a high glycemic index/load, meaning they stimulate the production of insulin, a fat storage hormone. Diets that increase insulin production have been shown over time to promote weight gain and increase the risk of developing diabetes, heart disease, some forms of cancer and a number of other inflammatory based diseases. In addition, cereals, grains and legumes contain lectins and phytates. These substances are not destroyed by cooking or though digestion and can result in damage to the intestinal wall, leaking of undigested proteins into the blood stream and immune reactions. Phytates can also prevent the absorption of certain micronutrients (vitamins and minerals).

Diets predominantly plant based (non-starchy vegetables, nuts and low glycemic fruits e.g. berries) along with grass fed, pasture raised poultry, red meat, pork and wild fish, offer a metabolic advantage based on the second law of thermodynamics as well as numerous health benefits derived from the anti-inflammatory phyto nutrients and essential fatty acids that these foods provide.


Get off That Aerobic Treadmill! Exercise burns calories. As the intensity that you perform an activity increases, the type of fuel you burn changes.  In general, at 50-70% of your maximum heart rate, fat is used as energy ("fat burning Zone"). From 70% on, glucose and eventually glycogen (stored carbohydrate) are used.

There are several problems with using the "fat burning Zone" for weight loss:

After a while, you become more efficient at burning fat, so you burn less of itOnce you run out of stored carbohydrate (glycogen), you start to break down muscle. This can have long term effects on your metabolism as well as healthIt is inefficient, i.e. it's a lot of work for what you get in terms of calorie (not necessarily fat) burningPeople generally crave carbohydrates after performing steady state cardio, because it is the predominant energy source burned during this type of activityIt is often used with a reward mentality, i.e. I spent an hour on the treadmill, so therefore I can eat more


A more efficient way to burn fat is through interval training, which intersperses short bursts of high intensity with active rests periods. EPOC (Excess Post exercise Oxygen Consumption), burns fat and lactate for several hours AFTER the exercise is finished- even while you sleep! Interval training can be done with resistance training, on a cardio machine, running hills or stairs, jumping rope etc. There are a number of studies that have compared relatively short high intensity interval sessions to lengthy slow go cardio sessions and the results show more fat loss as well as favorable metabolic changes e.g. lower cholesterol and triglycerides.


Eat a plant based (non-starchy vegetables, nuts and low glycemic fruits e.g. berries) along with grass fed, pasture raised poultry, red meat, pork and wild fishExercise: High Intensity Interval Training 2x/week; Resistance training 2- 3x/week; flexibility activities e.g. Yoga, pilates 2x/week or more and walking dailyPlay/recreational activitySleep 8-10 hoursStress management

Dr. Lecovin is a chiropractor, naturopathic physician and acupuncturist. He graduated from Los Angeles College of Chiropractic in 1990, earned a Masters in Nutrition from the University of Bridgeport in 1992, and then went on to complete the naturopathic and acupuncture programs at Bastyr University in 1994. He holds additional certifications in exercise from the National Strength and Conditioning Association, National Academy of Sports Medicine and International Society of Sports Nutrition.

Dr. Lecovin specializes in treating musculoskeletal pain and sports injuries by integrating trigger point acupuncture, soft tissue release, joint manipulation, corrective exercise and nutrition. In addition, he combines exercise and nutrition for weight loss, weight gain and performance enhancement.


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