Misconceptions surrounding the caloric value of fats
Supposed benefits associated with consuming fat is found in the fact that the caloric value attributed to fats, as outlined earlier, is 9 calories per gram of fat, as compared to 4.8 calories for carbohydrates and 5.2 calories for proteins. The obvious thinking behind the concept of eating fat is founded upon clear scientific data. If fats contain 9 calories per gram, or roughly twice the energy yield provided by either carbohydrates or proteins, then why bother with the lower caloric valued foods at all? We might as well cut to the chase and eat fats. There are a number of problems associated with eating fats as fuel. We shall first endeavor to straighten out this bent theory.
Machine burning and human burning of nutrients vastly different
While it is true that fats provide a yield of approximately 9 calories per gram, it is wrong to assume that the body can benefit from the entire 9-calorie figure. To explain: You will recall that the established caloric value of food is determined by burning the food in a calorimeter. Fats burn quickly in the calorimeter but they do not burn the same way in the body. Fats are essentially stored and used up as fuel later on. Fat burning through exercise occurs in the long-term energy system taxation venues. Fat is not burned up in 15 to 20 minutes nor is it burned up in even 45 to 60 minutes. It may take as long as 150 minutes before entering the fat-burning mode in the long-term energy system taxation.
Fats are there for sustenance in the event of a food shortage or short-term deprivation. The body also utilizes fats during prolonged exercise at different levels. The variance depends on several key factors involving biochemical specificity. These factors would include oxygen levels, blood free fatty acid levels as well as conditioning. The main point addressed is that the fat levels are so high that you are virtually risk-free of running out. Conversely, carbohydrate stores can become depleted very quickly. (Hultman E., Sjoholm H, Biomechanical causes of failure Jones H., et al., Eds. Human Muscle Power Champaign, II; Human Kinetics. 1986: 215-238.). The body is designed to store more fat than it will use in a protective measure against infringements on the system (Schultz Y., et al, Failure of dietary fat intake to promote fat oxidation a factor favoring the development of obesity; Am. J. Clin. Nutr. 1989; 50:307-314).
We do not use fats as fuel in event that tax anaerobic energy system. You may burn calories in a 20 minute cardio ride but you are not infringing on your fat stores. In the short-term and even medium length energy system fat remains untouched. In the short-duration events such as weight training (even though the weight training session may last 1- 1.5 hours it is performed over many short bursts (sets) of power output), the predominant source of energy is derived from the immediate energy substrates. Adenosine triphosphate (ATP) and creatine phosphate (CP) are the primary sources of muscle fuel. The body breaks down muscle glycogen and blood glucose into ATP much quicker than it does from fat.
The determination of the rate of breakdown is founded in the equation mol/min. The measures show that the rate of ATP synthesis from carbohydrates is 1.0 mol/min while the rate of ATP production from fats is only one/half of that rate at 0.5 mol/min. Once again strong evidence has been utilized to illustrate the need to check out the figures thoroughly in order to determine their accuracy with respect to the human condition. Adding to the startling revelation of the misleading aspects of the caloric value of foods is the fact that during anaerobic exercise the energy formation of ATP increases dramatically from its normal 1.0 mol/min to 2.4 mol/min. This figure provides us with the surprising about-face figure that sees carbohydrates delivering almost 5 times the energy of fat (Ahlberg B. et al., muscle glycogen and electrolytes during prolonged physical exercise. Acta. Physiol. Scand. 1967,70:129-142).
Difference in respective roles of complex carbohydrates and complete protein
Even when comparing the actions of carbohydrate and protein there exists a wide discrepancy of the respective roles of these two ingredients. It is shown that despite possessing similar calorie counts (recall: carbohydrates 4.8 calories per gram and protein 5.2 calories per gram) carbohydrates and proteins provide very different services in the body. Carbohydrates provide muscle and organ fuel to provide for muscle growth and resistance to fatigue. They provide the anti-catabolic action to preserve valuable protein stores and they also add one more major gift, they provide for fat burning. ("Fat burns in the Flame of the Complex Carbohydrate"). For these reasons, complex carbohydrates are considered an ideal pre-workout meal. Protein provides the all-essential building blocks of muscle (amino acids) and is vital to muscle growth in terms of providing for a positive nitrogen balance within the muscle. Because of this role, protein is considered an ideal post-workout nutrient for anaerobic training.
More vital consideration of food value than mere calorie count
Remember, both carbohydrates and proteins offer similar value of calories per gram yet they are considered as ideal nutrients for far different reasons and are recommended to be eaten and contrasting times! Once again, if calorie count was the predominant consideration as to their value, then would it not make sense to then presume that they would be equal in terms of the roles that they play. If such consideration would emerge as the keynote value of the food, then what possible difference would the time of consumption make? The factors of biologic function yield that caloric value does not provide the full story for total value of the nutrients that we consume. Once again, we see that the caloric value of the foods offers not only an inaccurate assessment of the true value of the food but a totally misleading evaluation.
More caloric value misrepresentation found with same-food categorizations: Biologic Value (B.V.) of protein established as viable measure
Taking the concept of the caloric value misrepresentation of true food value even further, we can analyze the differences in food value between "same-food" categories. That is, when an analysis is provided between complete and incomplete proteins for example the caloric value remains the same at 5.2 calories per gram. However, the value of complete protein far outweighs the value of incomplete protein. According to the charts established by nutritional experts to assess the value of food the "biologic value" (B.V.) of complete proteins is well ahead of the B.V. of incomplete proteins. In fact, even different proteins from the complete protein group are evaluated by their biologic value. Not all complete are considered as "valuable" yet they all have the same caloric value attributed to them.
Complex carbohydrates superior to simple carbohydrates in value
Once again, the concept of "same-food" categorization assessment appears with the evaluation of carbohydrates. Interestingly, the reference to biologic value (B.V.) utilized in the assessment of various proteins is not used when evaluating carbohydrates. However, it might be thought that there should be a consideration of biologic value of carbohydrates when comparisons are made between simple carbs and complex carbs. Even more interesting might be the fact that not only should distinctions between simple and complex carbs be presented but comparisons of simple carbs to simple carbs and complex carbs to complex carbs evaluation should be presented. There are many different sources for both groups that can be compared to each other. However all carbohydrates are grouped together with reference to caloric value. Again, the figure offered is an across-the-board (4.8 calories per gram) measure of the value of the food. Once more, we can appreciate the lack of required clarity in food value assessment when mere caloric content is the only measure provided. Complex carbohydrates and simple carbohydrates should never be compared for neither value nor function.
What is More Important – Caloric Count or Biologic Function?
Let us begin with the values attributed to both carbohydrates and proteins. There would be immediate suspicion raised as these two nutritional groups are worlds apart with reference made to the roles each provide. Please read the sections on the role of carbohydrates and the role of protein for a complete analysis. In brief, carbohydrates provide four main functions that proteins do not offer. Carbohydrates provide for muscle fuel, organ fuel, central nervous system fuel, serve to provide for protein sparing effect and provide for fat metabolism. This concept of fat metabolism will be re-addressed in the comparison of carbohydrates and fats. Proteins meanwhile, provide for nitrogen restoration and the providing for an anabolic-versus-catabolic condition in the body. Therefore, if the caloric count were the only consideration, or even if it were only the keynote consideration to nutritional guidance programming, the caloric count would be the ruling force of the foods that we eat and not the metabolic reactions and conditions that they provide.
Therefore, it would not be of any significance to compare the calorie counts of two food categories, proteins and carbohydrates. In establishing the respective value of these, favoring one over the other in any of the meals -including pre-workout and post-workout ingestion- on the basis of caloric values would be of no positive significance. The point being emphasized is what we eat and when we eat. It is crucial to the health and fitness level attainment of the individual. If you believe that carbohydrates and proteins must be the same because of their similar caloric value, you might want to revamp that thinking. The respective roles that each food category offers are the true measure of this value.
An interesting study would be to eat a meal comprised of proteins before the workout and then try another pre-workout meal comprised of complex carbohydrates. Your body's response to the workout will provide you with the right answer. Added to the information will be the body's reaction following the workout. You will be much more fatigued and you will be hungry throughout the day. You will be constantly eating trying desperately to catch up on the nutrients that were burned up because of the ill-advised pre-workout meal. Do the same with the post-workout meal. Once again, the concept of eating the right food at the right time will highlight the crucial aspect of the food's biologic function. We can benefit from the importance of the role of the foods that we eat rather than mere amount. The time of consumption clearly rules over the caloric amount. The ideal meal prior to exercise would be one comprised predominately of complex carbohydrates (60%) with some protein (30%). The predominant nutrient following intense anaerobic exercise (such as weight training) would be complete protein. Note the reference to "predominant" nutrient. It would be necessary to also include complex carbohydrates in the anaerobic post-workout meal. A post workout meal featuring both complex carbohydrates and protein equally would be ideal following taxing aerobic training in order to restore lost glycogen supplies as well as nitrogen. The training mode (anaerobic or aerobic) would determine the emphasis of the post workout meal.
Summary
It is hoped that by addressing the vital issue of biologic value and function (as opposed to mere caloric count) would provide a much more viable approach to nutritional program setting than merely outlining a diet based on caloric count. The points raised above should allow for the realization that far too much emphasis is placed on the how much of eating rather than on the far more vital issues of what should be eaten and when it should be eaten. The role of the various foods that we eat should be understood before proper dietary planning can be implemented. While it is hard to discard a century-old concept, counting calories at the very least should be viewed as something that can be done after the required nutrients are put into place and not before. As trainers we should allow the trainee to work with the foods and the results monitored as opposed to putting the trainees on pre-determined calorie counts which most likely would be off target. It would be much better to place the horse squarely behind the cart as opposed to in front of it. In so doing, trainers would be well placed with respect to logical progression in the quest to provide proper nutritional programming.
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