By: Chris Vann, MS (c), CSCS
The Importance of Macronutrients
The pursuit of a great physique or increased strength involves many factors that affect the eventual outcome. Nutrition is one of the most important influential factors in this process and, in particular, energy or calorie balance. Calorie balance can be defined as the result of calories consumed vs calories expended over the course of a 24 hour period. A calorie is a unit of heat energy. A calorie (i.e., technically a kilocalorie, but referred to as a calorie herein) is defined as the amount of heat energy required to raise the temperature of 1 gram of water 1 degree Celsius. In general, the number of calories expended should exceed the number of calories consumed for notable reductions in body fat. This is referred to as a negative calorie balance or calorie deficit. Conversely, to realize significant increases in muscle mass, consuming more calories than expended is a logical strategy. This is known as a positive calorie balance or calorie surplus. Recently, as proof of principle, a Kansas State University Professor of Nutrition lost 27 pounds consuming mostly snack cakes while seeking to ensure a negative calorie balance. This runs counter to the assumption that one can only lose significant amounts of body fat via “clean eating”. Although the quality of food (i.e., nutrient profile) is certainly relevant to consider for health purposes, it turns out that calorie balance is the primary influential factor pertaining to significant alterations in body composition while food quality plays less of a role. With that said, calories are not exclusive of macronutrients. Macronutrients are substances required to sustain life. The three macronutrients are: protein, carbohydrates, and fat. Each of these macronutrients contain a certain amount of calories per gram. Specifically, protein and carbohydrates contain ~4 calories per gram, while fat contains ~9 calories per gram. Of note, alcohol, although enjoyable upon occasion, is not required to sustain life, yet yields ~7 calories per gram warranting its exclusion in this discussion. Previously, my good friend Cody Haun wrote about setting calorie totals relative to metabolic rate, activity levels, and other factors for body composition purposes. In this post, I want to provide some direction for setting macronutrient totals more specifically to further promote improvements in body composition or performance.
Inherently, setting macronutrient totals follows setting the appropriate calorie value on a per-day basis; which will depend upon physical activity and other factors each day. Upon calculation of the appropriate calorie value for each day, macronutrient totals can be calculated to improve the outcome of the training process. To accomplish this, we need to know when to prioritize each macronutrient and why it is important to begin with. Recently, we compiled what we feel is some of the most important information regarding these procedures and provide greater detail of these processes and calculations in the SOMA Nutrition and Recipe Ebook. In our opinion, and the opinion of other experts in the field, macronutrient partitioning is the second most important factor to address in construction of a diet, while calorie balance is of primary importance, and the timing of macronutrients follows just behind macronutrient totals for optimal outcomes. While other factors are certainly important (e.g., micronutrients, fiber intakes, etc.), this post is meant to serve to aid in the appropriate calculation of macronutrients to consume per day for more ideal outcomes. With this in mind, protein is first discussed followed by information and rationale for calculating effective doses of carbohydrate and fat totals per day, relative to the aim of the training outcome.
Protein is the nutrient that, especially in the case of an athlete or an active person, should be prioritized. Proteins are defined as large molecules made up of one or more chains of amino acids, joined by peptide bonds. When dietary protein is consumed, these bonds are broken during digestion and amino acids can be made available to cells for various physiological processes. Protein is essential for much of the structure, function, and regulation of body tissues. The composition of the human body and implications of protein deficiency on health and performance rationalize the setting of dietary protein totals as a first step to partition calories on a daily basis. Forbes showed that the human body is comprised of ~20% protein and ~50% water, implicating that ~75% of the human body is composed of these two substances. Of particular importance to an athletic or fitness-oriented population is the composition of striated muscle, which, when removed of water, is ~90% protein. With this in mind, it is logical to prioritize protein to ensure you are getting an adequate supply of amino acids to facilitate the synthesis of new proteins important for recovery and adaptation to exercise.
Training can elicit damage to muscle proteins which can be tagged for protein breakdown. Providing amino acids through either supplemental protein or whole food sources can affect muscle protein balance by reducing the amount of muscle protein breakdown or by providing amino acids that can be utilized to facilitate the synthesis of new muscle proteins. The dosing of protein is highly debated and varies depending on what source of information analyzed. As an example, the United States Department of Agriculture recommends 0.5-1.0 g per kg of body weight per day (g/kg/day), while the National Strength and Conditioning Association presents recommendations of 1.5-2.0 g/kg/day. Furthermore, upon analysis of other sources, one is sure to find other values that can be interpreted as safe and/or effective. For example, Dr. Jose Antonio has performed multiple studies investigating protein overfeeding and alterations in lean and fat mass with consumed values in these studies ranging from 0.8 g/kg/day to 4.4 g/kg/day. One thing that Antonio and others have shown of particular interest, is that when protein is dosed in relatively high amounts, greater increases in lean mass and concurrent decreases in fat mass can be realized. Although this data is certainly promising, it is debated if this practice is safe and effective over a long period of time. Antonio’s studies have lasted ~6 months on average, and, outside of subjects potentially fatiguing jaw musculature, there seem to be no clear harmful effects on overall health. Hoffman has also shown similar increases in lean mass and reductions in fat mass when athletes consumed more than 2.0 g/kg/day of protein during a 12 week resistance training study. This study also suggests that the subjects who ingested 2 g/kg/day also improved strength to a numerically greater extent than subjects consuming less protein. Given this data and data from the NSCA, ACSM, and others, it is plausible to recommend a starting value of ~2.2 g/kg/day (1 g/lb) of dietary protein.
Another factor worthy of strong consideration when constructing a diet is the effect of different macronutrient totals on training intensity, particularly in athletes regularly training at a high intensity. The movement patterns involved in various athletic endeavours tend to be rapid and involve high amounts of force production. Repetition of these types of activities generally involves the breakdown of muscle glycogen, the storage form of carbohydrates. As a result of the energy demand during training, muscle glycogen can decrease. Sufficient carbohydrate intake can help augment performance during training with special attention being given to the four hours around the time one completes a training session. This period of time can benefit an individual’s performance during training via the consumption of high glycemic carbohydrates to not only provide fuel prior to a session, but also to replete glycogen post training for successive training bouts to follow. To provide a sufficient amount of carbohydrate on a daily basis, the energy requirement of each workout should be estimated among other factors like resting metabolic rate, non-exercise activity thermogenesis, and the thermic effect of food. Days that are designated as “off” do not require as much energy as days on which training occurs. Similarly, high-volume training tends to reduce glycogen more than low-volume training. Appropriate carbohydrate intake should be calculated with attention paid to these factors. Generally, this results in values ranging from ~2.2 g/kg/day on non-training days to somewhere between 3.3 g/kg/day on lower-volume training days to upwards of 6.6 g/kg/day on higher-volume training days.
The importance of consuming adequate amounts of fat cannot be understated due to its contribution to anabolic hormone synthesis and its integral part in cell membranes (i.e., phospholipid bilayer). As mentioned previously, dietary fat contains ~9 kcal per gram, which is roughly 2x’s the amount of energy per gram of carbohydrate or protein. Another relevant property of dietary fat is related to its effect on the digestion of nutrients consumed concurrently (e.g., a meal containing each of the macronutrients). In general, a notable amount of fat consumed with carbohydrate and protein food sources can slow the digestion of carbohydrate and/or protein. Also, during periods of consuming a calorie surplus, fat tends to be a practical calorie buffer given its energetic density and the fact that it tends to be less satiating. The fine folks at Renaissance Periodization recommend a minimum fat intake of ~20% of your kilogram body mass in grams (i.e., ~10% of bodyweight [lbs] in grams) to provide insurance that a sufficient amount of dietary fat is available for physiological functions discussed prior. This would result in someone weighing ~200 lbs consuming ~20 grams per day. In many cases, fat should likely not drop below 20% of daily caloric intake with much of that coming from essential fatty acids, monounsaturated, and polyunsaturated sources. Typically, however, calories from fat can be easily calculated by making up the remaining calories after protein and carbohydrate values have been appropriately set. This is accomplished by dividing the remaining calories by 9.
With regards to effective dosing of calories to elicit better performance or alterations in body composition, calorie balance is the chief priority. The partitioning of macronutrients is priority number two. Appropriate calculation of calorie and macronutrient totals must consider predicted total daily energy expenditure while also keeping future fitness or competitive goals in mind for longer-term planning. To reiterate the above recommendations, baseline or starting values for protein can confidently be dosed at ~2.2 g/kg/day and protein should be prioritized when calculating daily macronutrient totals. Carbohydrates are an incredibly valuable tool that can augment performance and resultant adaptation with plausible doses ranging from ~2.2 g/kg/day on non-training days to as high as 6.6 g/kg/day on hard, high-volume training days. To be clear, setting carbohydrate totals will depend on the intensity, volume, and frequency of training. Fats possess a high energy content per gram and can be used strategically when electing certain daily totals and timing strategies. Fat consumption should likely not exceed a minimum daily gram value of 20 % kilogram body mass (e.g., 100 kg person would consume ~20 g). These values should be logically altered depending on training and body composition goals for continued progress. This is where the usefulness of a coach with experience in this area can provide direction and why APLYFT is such a great concept (i.e., connecting experts with clients). In the next article, we will discuss timing strategies of these macronutrients, and how nutrient timing can affect adaptive outcomes.
Thanks for reading and feel free to reach out with any questions. Best wishes on your training endeavor!
Chris Vann, MS, CSCS
-APLYFT Science Consultant