Common Sports Nutrition Questions
- Is alcohol bad for athletes and why?
- Can branch chained amino acids (BCAAs) help an athlete at all?
- I have heard that glutamine will help me perform better?
- Can an athlete be “optimally” successful as a vegan?
- Does carbohydrate loading work for endurance athletes?
- What fat loss supplements should I take if I’m an athlete?
- What are MCT’s and why are they helpful for athletes?
- How come we as athletes don’t require much fat during the “post-workout” period?
- How do I improve my insulin sensitivity or fight increased hunger with higher carbohydrate intakes so I can lose weight and be healthier?
- Is it better to eat 3 meals per day or 5-6? And what are your thoughts on intermittent fasting approaches for athletes?
- Is a calorie a calorie?
Answers to Common Sports Nutrition Questions
1. Is alcohol bad for athletes and why?
I know that this question probably seems ridiculous and blatantly obvious, but it needs to be addressed for the sake of completeness: “When ingested, alcohol is very rapidly absorbed into the bloodstream compared to the rate of other foods. Some absorption of alcohol occurs within the mouth, esophagus, and stomach, with the majority of absorption occurring in the small intestine.”(2) From here, alcohol is converted to acetylaldehyde and then Acetyl-CoA, where it is either converted to energy or stored as fat. And since alcohol carries with it a high content of energy at 7 calories per gram, fat gain may be even more likely. Moreover, in one study from Hetherington et. al, individuals who consumed a pre-load alcohol 30 minutes prior to a meal consumed more food than those who didn’t.(124)
Last but not least, alcohol acts as a diuretic, expresses direct effects on the central nervous system, is a depressant, decreases testosterone production in the testes by inhibiting the leydig cells, and will ultimately impair athletic capability. Any athlete looking to truly optimize their performance should refrain from consuming alcohol. Period.
2. Can branch chained amino acids (BCAAs) help an athlete at all?
BCAA’s are arguably one of the most popular muscle building/sports performance supplements on the market today. On paper, BCAA’s sound amazing. BCAA’s make up approximately one third of the protein content of muscle and include the amino acids leucine, isoleucine and valine. Unfortunately, research for BCAA supplementation in the presence of adequate protein intake for a reference athlete or individual does not seem to promote a benefit.(107)
Another example can clearly be seen in a study by Churchward-Venne et al., 2012. 24 males participated in a study that involved being sectioned into groups that supplemented with either a complete whey source versus a lower dose of whey protein combined with leucine and other essential amino acids. The results showed that even though the low dose combined with EAA’s was able to augment skeletal muscle growth for a few hours following exercise, only complete whey could continue to keep up the pace and keep the muscles growing.(125) Keep in mind people, the global market for sports based nutrition is lucrative and is projected to increase by over 50% by 2022.(126) Yes, some supplements do work but this is a billion dollar industry we are talking about, and to maintain these numbers they are going to have to allow some supplements to slide through to keep up with the bottom line. Optimizing your performance comes a distant second my friends.
3. I have heard that glutamine will help me perform better?
It is the most abundant amino acid found in blood plasma and skeletal muscle and accounts for over 60% of the total intramuscular free amino acid pool.”(2, 127) Glutamine has been another frequently hyped up supplement over the years but shows little promise throughout the scientific community in an attempt to enhance athletic performance, unfortunately. In one study, daily glutamine supplementation over the course of 6 weeks while practicing in a resistance training protocol did not affect body composition, muscular performance, or protein degradation compared to a placebo.(128)
The most notable study on glutamine for athletic performance came back in 2001. Unfortunately, glutamine sounds like a god on paper as it serves a number of biological roles, but according to Kevin Kuhn, a large number of studies were performed in vitro, rather than in vivo dealing with an actual living body, which both you and I are.(144) In 2001, Candow performed an enlightening study on 31 individuals who were either male or female between the ages of 18-24. They were randomly assigned to two groups. One group utilized glutamine while the other group was administered a placebo of maltodextrin. Each group performed an approximate microcycle (6 weeks) of resistance training in classic hypertrophy training zones. After completion of the program, subjects were tested on various measures including 1rm Bench Press, 1rm Squat, peak knee torque, body composition utilizing a dexa scan, and muscle protein breakdown via 3-methylhystidine levels in the urine, a marker of breakdown. Contrary to the in vitro studies, there were no significant differences between each group, strongly indicating that you should save your money and ditch glutamine if you are an athlete. (129, 130)
4. Can an athlete be “optimally” successful as a vegan?
Let’s first take a look at a limiting factor with regards to vegan based protein sources, comparative to animal based proteins dense with complete protein. When we eat meat, eggs, and other animal sources of protein then there is no need to fret about fulfilling a complete amino acid profile. Plant based sources, on the other hand, lack one essential amino acid and need to be complemented by another source to deliver all amino acids. For example, plant based protein sources are often guilty of being unable to deliver a single amino acid known as the ‘limiting amino acid.’ For example, grains’ limiting amino acid is lysine, but grains are high in the amino acid methionine. Therefore, grains match well with legumes, which are low in methionine but high in lysine.”
So greater consumption of complimentary proteins becomes essential to make sure that all potential deficiencies are accounted for, while also giving some extra supply of amino acids since plant based proteins are only 85% digestible, compare to animal sources which scale around 95%.” (2)
Plant Based Meal Combo’s:
- Stir fried vegetables and tofu over rice (soy and grains)
- Vegetable chili with cornbread (legumes and grains)
- Oatmeal with nuts and soy milk (grains, nuts, and soy)
- Spinach salad with vegetables, garbanzo beans, and sunflower seeds (legumes and seeds)
Real quick, I want to note that there is not a nutrition manual seeking to answer which diet is supreme to the other in terms of general health. With the growing popularity of vegan based diets in contemporary culture, I just thought it would be helpful to explore this nutrition option for athletes looking to perform better in their sport and that’s it. With that being said, a vegan diet does seem plausible, although further investigation does seem to be warranted. According to a study by Barr et. al 2004, here are 5 brief areas of concern for those who opt to embark on a vegan diet and still desire to perform at a high level: (131)
- Appropriate supplementation
- Protein intake
- Non-anemic iron deficiency
- Muscle creatine concentrations (146)
Vitamin B-12 deficiency is a common area of concern for vegans and this specific vitamin may need to be supplemented.
Adequate protein intake, although more difficult to come by perhaps for vegans vs. non vegans, does seem attainable to support proper athletic development. For example, a study from van Vliet, 2015 found that plant protein is typically less anabolic than animal protein for several reasons.(132) Some include a reduced amount of essential amino acids, in particular leucine. Greater excretion rates, proposed digestibility issues and more. However, the author did state that several strategies could be used to improve the anabolic response of a protein based meal primarily derived from plants. Including a higher variety of plant based protein sources, supplementing the amino acids leucine, lysine, and methionine, and eating greater amounts of plant based protein sources. Gorissen et. al agrees that compensating for reduced functional protein content by eating higher quantities of plant based protein is one way to go.(133)
Iron and creatine are present in high levels with traditional meat sources. However, according to this particular study, there are two commodities may need to be monitored carefully in vegans to prevent the unwanted onset of symptoms which could impact athletic performance.
5. Does carbohydrate loading work for endurance athletes?
Carbohydrate loading is a nutritional strategy that has been practice by mainly endurance athletes for decades and it works. Otherwise I don’t think they would still be doing it at this point. When we decide remove or cut down on carbohydrates for an appreciable period of time, the enzymes that handle this nutrient are reduced in number by down-regulating or lowering their activity in the body. Once they are re-introduced back into the diet, our body will be ill-equipped to use and store carbohydrates and we may be left hungrier from an inability to handle and fill up our carbohydrate (glycogen) stores. Eventually we will adapt back, but it’s not immediate. Secondly these enzymes will compensate and up-regulate or increase their activity resulting in extra storage of carbohydrate sources above baseline levels. “The end result after depleting and then loading is they’d end up doubling their muscle glycogen storage capacity from an original 300-500 grams all the way up to around 800-1000 grams.”(149)
What does this mean? “That would be a minimum of an extra 4 pounds of water and glycogen resulting from the additional 500 grams of carbohydrate storage above baseline.”(134) Meaning if you are a hardcore endurance athlete gearing up for a long and strenuous event that utilizes the approach below. For everyone else, stabilize your carbohydrate intake over the long-term and you will be perfectly fine.
Stage 1: Depletion
Day 1- HIIT to exhaust all glycogen stores in muscle and liver (18-24 hours)
Days 2, 3 and 4- 60-100g carbs with high percentage of protein and fat in the diet
Stage 2: Loading
400-700g carbs per day with normal percentage of protein in daily diet
Competition Day: high carbohydrate pre-meal
6. What fat loss supplements should I take if I’m an athlete?
First, make sure to keep your calorie deficit (aka calorie cut) at a minimum, trying to maintain strength and performance while cutting is very hard since you’re central nervous system takes a hit based on past information, however recent research on sprinting and jumping performances of athletes can sustain and even improve after a few weeks of moderate dieting. A 20-30% deficit seems to work well for most and is a good general recommendation for those who want to cut weight and still maintain and even slightly improve performance. Also, make sure to keep your protein intake moderate to high. This will help fill you up and preserve muscle mass and supply some extra energy if necessary.
#1 Caffeine/Green tea extract
These two thermogenics can help suppress appetite to a degree, and help you burn some extra calories each day which add up in the long run. They are also both loaded with antioxidants and have other benefits for athletes in addition to what they provide for fat/weight loss efforts.
#2 Calcium- fat cell mobilization
I’m not sure how valid this advice is anymore because I couldn’t find any updates, but Lyle McDonald shared some information that calcium supplementation could help mobilize fat from fat cells.
#3 Lots of hard work!
No supplement will do anything if you aren’t eating right and busting your ass on a regular basis. In terms of priorities, put diet and nutrition as complementary and when you have these two areas dialed in then worry about your supplements to put the icing on the cake.
7. What are MCT’s and why are they helpful for athletes?
Medium chain triacylglycerols deliver energy faster than conventional fat energy sources. Basically, fats typically undergo a lengthy, complicated process where they can’t gain immediate access into the bloodstream. Fortunately, this is not the case for MCT’s. Eventually, MCT’s are converted to medium chain fatty acids (MCFA’s). The speed of uptake in cells and their burn rates make MCFA’s a more efficient source of energy. Moreover, because of rapid digestion and absorption, MCFA’s may possess a glycogen/glucose sparing effect which could enhance performance in endurance type athletes.(128)
8. How come we as athletes don’t require much fat during the “post-workout” period?
Fortunately, fat stores have a very high energy density (9 calories per single gram or 3500 calories per pound of fat). This means there is generally plenty to go around if the need arises during exercise, recovery, etc. The same cannot be said for carbohydrates and proteins though as their stores and pools are much smaller in comparison to fat. One study showed a decrease in P70S6K activity when fat was consumed post-workout. P70S6K is a potent muscle building signaler in the body, so we better keep it happy and focus on protein, carbohydrates, and hydration instead.
9. How do I improve my insulin sensitivity or fight increased hunger with higher carbohydrate intakes so I can lose weight and be healthier?
The issue of insulin sensitivity is real. Some people, especially those who carry excess body fat, will probably respond better initially with less carbohydrates (40% or less). Insulin resistance tends to occur after 15% body fat from what I’ve heard repeatedly in a predictable progression sequence involving the liver, muscle tissue, and then eventually body fat. Please keep in mind that it’s not necessarily the carbohydrates per se that is the issue here, but rather the over-signaling of receptors for insulin from too much food intake.
So what happens that prevents glucose and consumed carbohydrates from entering muscle tissue in those that are susceptible? Well, for starters, there are two transporters called GLUT1 and GLUT4 which assist with the uptake of glucose into our cells, with the majority of uptake occurring from GLUT4 and its pathway, regardless of the type of cell type (i.e. fat, muscle, etc.) Unfortunately, not as much research has been conducted on muscle cells versus fat cells for different reasons, so keep this in mind. Nonetheless, the transporters need to re-locate to the surface of the cell in order to bring glucose into the cell effectively.
Supposedly, the pathway in which the transporters travel is poorly designed in the cell and they tend to reside deep in the cell and are called out when insulin arrives. Unfortunately, a lot of this may be genetically regulated and from what I’ve read, muscle cells lack some of the structural components in the right proportions to prevent insulin resistance. For example, syntaxin 4 is a gene that is responsible for translocating or relocating GLUT4 to the surface of the cell. “If human muscle tissue resembles that of mice with respect to the expression of syntaxin 4 and its functional limitation on GLUT4 translocation, any genetic condition that downregulates the activity of the level of syntaxin 4 is likely to predispose to insulin resistance.”(135)
To make matters worse, there are two individual spots where glucose can dock at muscle cells and I will spare you the names of each because it really doesn’t matter. Ironically, GLUT4 tends to dock at site that involves a channel that carries less syntaxin 4 potentially adding to the possibility of resistance.(135, 136, 137)
Also recall that both protein and fat stimulate insulin appreciably, just not quite as much as carbohydrates, so with people’s common logic of carbohydrates make you fat, it would only be fair to state that the other two macronutrients provide to fat stores as well, but they don’t when all is said and done unless “calories” are too high relative to daily energy expenditure levels. Also keep in mind that even in the absence of insulin we can store fat via an enzyme called LPL (Lipoprotein Lipase).
Some credible authorities have also stated that overall sugar consumption has been on the decline in the past two decades, yet obesity is rising. Huh? Put down the fork sooner rather than later and your insulin receptors and associated structures will likely thank you for it. Also, weight training and exercise in general will help tremendously with insulin function both from experience and research on the matter. Here are some simple foods that you can also incorporate into your meal plans that have been advocated to help with insulin sensitivity, and also keep in mind the aforementioned genetic factors as well that play a role with insulin functioning:
- Curcumin
- Ginger
- Garlic
- Cinnamon
- Fish oils
- Coffee
On a final note, sleep has been shown to significantly impact insulin sensitivity. I discussed sleep briefly in the carbohydrate section, but I in a way feel like I did an injustice to the topic since it provides so much for the human body and our ability to function. But this is a nutrition book so I wanted to stay on topic as much as possible. Make sure you get your ZZZ’s, people.
10. Is it better to eat 3 meals per day or 5-6? And what are your thoughts on intermittent fasting approaches for athletes?
Ever since I can remember there has always been an unrelenting debate about whether it’s more beneficial to eat larger meals or smaller more frequent feedings. The answer isn’t clear and it’s really not that important if calories, carbs, fats, and protein are similar according to research and you aren’t too far to either end of the spectrum. For instance, many experts claim a higher boost in metabolism with more frequent meals in the ball park of 5-6 feedings per day. However, one study found a 15 calorie burn advantage with five meals per day vs. just one.(153) Not groundbreaking information by any means. (138)
Another study on the topic published by Dr. Leady found that three meals generated a stronger feeling of fullness versus six meals, although there was a 10% discrepancy in protein intake which very well could have affected eating behavior since protein possesses a strong influence on appetite. On a final note, hormones carry strong half-lives often times by remaining in our bloodstream, and their specific effects could be felt for days and even weeks. For example, according to nutritional mastermind Lyle McDonald, sympathetic nervous system (SNS) output only drops around 5% within the first week of dieting. This means that if a Person A was burning 2500kcal at the start of his or her diet, then by the end of week #1, there would only be a reduction of around 100kcal. This issue has been blown way out of proportion it seems.
You’ve seen the benefit of eating protein dispersed over the entire length of an entire day versus one giant feeding for improved muscle protein synthesis purposes and performance outcomes in athletes in the protein section which was discussed earlier, so we are good there.(100) The only other issue in regards to meal frequency for athletes would involve weight/fat loss efforts.
In non-athletic populations, altering meal frequency isn’t a written rule yet and researchers note that further investigation is necessary, but in those that aren’t active a higher frequency could help with hunger and appetite issues. However, “In the face of restricting caloric intake for weight loss, altering meal frequency has shown limited effects on body composition.”(85) So, when all is said and done, meal frequency really won’t mean much for losing weight, building muscle, or raising performance levels.
And this brings up a great topic. How well intermittent fasting works for athletes, or does it? Intermittent fasting involves eating all of your food within a specific window of time (usually 8 hours), followed by an extended delay in food consumption. With everything I just mentioned what do you think the verdict will be? When it comes to athletes, moderate daily feedings are where it’s at for everything performance related. Period.
A recent study from Svendsen et al., 2018 reported that both continuous or normal energy restriction and intermittent fasting resulted in weight loss, and improved cardiovascular markers in both women and men with abdominal obesity. However, feelings of hunger become difficult to deal with over the long-term and can affect adherence to intermittent fasting. (139) Any type of starvation diet for something our body deems essential seems to backfire in the end, even if it’s on the low end of the calorie time restriction range.
11. Is a calorie a calorie?
Sorry to burst any of your bubbles folks, but yes, a calorie is simply a unit of heat. Some macronutrients carry more calories than others. Here is the Atwater factor chart which illustrates my point precisely.
Atwater General Factors
Nutrient | Energy Value (kcal/gm) |
Fat | 9 |
Carbohydrate | 4 |
Protein | 4 |
Alcohol | 7 |
Obviously the effects of each macronutrient on performance, recovery, etc. will differ as you’ve seen so far in this book, and I think that it what was meant when proponents of the old saying that “a calorie is not a calorie” originally said it.
About Travis Hansen
Travis Hansen has been involved in the field of Human Performance Enhancement for nearly a decade. He graduated with a Bachelor’s degree in Fitness and Wellness, and holds 3 different training certifications from the ISSA, NASM, and NCSF. He was the Head Strength and Conditioning Coach for the Reno Bighorns of the NBADL for their 2010 season, and he is currently the Director of The Reno Speed School inside the South Reno Athletic Club. He has worked with hundreds of athletes from almost all sports, ranging from the youth to professional ranks. He is the author of the hot selling “Speed Encyclopedia“, and is also the leading authority on speed development through the International Sports Sciences Association.