I've been fascinated with nutrition over the last 20 years. It started after football when I wanted to shed some unwanted bulk and bulge. Once I took an interest, I learned that I missed some potential performance gains in my younger years by not paying closer attention to fueling my body properly. No question, we can get away with things when we are younger, but sound nutrition can give us an edge in competition, no matter the level or our age.
A recent study I read, which can be found here, led me to share some of my thoughts and experiences with nutrition through the years as an endurance athlete and coach. The study is about energy availability and has some great charts in regard to supplements, doses and macronutrients needed to support training. Take a look for more details and links to other studies in the references. Take note of some of the authors and find them on social media as many of them share great info often.
ARE YOU EATING ENOUGH?
45 calories per kilogram of Free Fat Mass (FFM) body weight per day is what is recommended to support a high level of training. I consider that about 12 hours a week and if training more, then one needs to adjust upward. So what does that look like for a 154 pound athlete with 8% body fat? Let's convert to kilograms and find FFM (lean body mass).
154 pounds / 2.2 = 70 kg body weight
70 kg - 8% Body fat (5.6 kg) = 64.4 kg FFM
64.4 FFM X 45 cals/kg = 2898 calories per day
About 2900 calories and I believe 50-60% should come from carbohydrates, which is 1450-1740 calories per day from carbs. We can get into carbohydrates - periodization, training low, and so on at a later date as there can be a place for these things in my opinion, but it has been shown that most endurance athletes respond best to a high carbohydrate diet.
About 2 gm/kg of body weight should come from protein, which is 140 gram protein for our 154 pound/70 kg athlete divided into 4-5 feedings through the day. 4 cals/gm of protein, so that is 560 calories.
2900 cals/day - 1740 cals carbs = 1160 cals - 560 cals protein = 600 cals remaining for fats. 9 cals/gm of fat so that is about 66 grams of fat for the day.
Another way to figure out energy needs would be to use an online calculator or an app such as My Fitness Pal to find the amount of calories you need per day for normal body functions - basically staying alive. I believe this comes in around 2000 calories per day for many average sized male cyclists (160 pound range). If you train with power, you can look at how many kilojoules (kj) you burned on the bike over the last few weeks and get an idea of your average burn per week. For practical purposes one kj is about equal to one calorie burned. I'd guess that would come in around 600 kj or calories per hour. So 12 hours riding per week is around 7200 kj or calories burned from exercise and 14,000 calories (2000 cals/day x 7 days) is needed to stay alive. Add them together and you get 21,200 calories per week. Divide by 7 and that gives us 3000 cals/day. Pretty close to the 2900 cals using the FFM formula above.
So again, about 2900 calories per day will be in the ball park for the athlete to stay in an energy balance and maintain weight and support training. If the goal is to shed some weight for a key event then implementing a 300-500 calorie per day deficit would be recommended to help that goal and not hinder performance to a point. 154 pounds and 8% BF is quite lean, so not sure shedding any weight is advised for the example athlete. Resistance training and ample protein intake as described above have been shown to help retain muscle mass when shedding unwanted body fat. I'd bet many athletes are not eating enough in an effort to try and lose weight and the net result is under performing and also not reaching body weight/composition goals. Fuel the machine!
EAT HOW YOU TRAIN OR THE SAME EVERY DAY? - Both work
If you are reading this, I'd bet you are in the 'I want to shed some unwanted body fat' group. Many opinions out there on what is the best approach to dropping some LBs. Calories In/Calories Out (CICO), Carbs are the enemy, Dairy and Grains are toxic, etc. I will leave those details alone for now but will say that it does come down to an energy balance in my opinion. An energy deficit needs to be present to shed the weight. That can be done in different ways. One is to eat like you train. In this approach, you have a baseline amount of food you eat daily that you need to survive (generally 1500+ calories per day pending size, gender, weight management goals) and if you burn 1200 calories in training that day, then you eat 1500 (or more) + 1200 = 2700 calories that day for energy balance, as an example, and 2400 cals would yield a reasonable deficit. If training was intense, then carbs could be increased to 6-10 gm/kg that day. If training was low intensity, then 3 gm/kg of carbs may be enough. This approach can be good for some as you eat more food and more carbs on the days you train hard and less on the others and at the end of the week the calories and macros all equal to what you need to be healthy and perform, which leads to the other approach - eat the same every day. I find this second approach more sustainable and easier to keep track of. I tend eat the same amount of calories every day regardless of training. I just adjust the carbs a bit. Some days maybe a bit more calories and some a bit less, but overall consistent and I do not stress over the minutia. It makes the recovery days more manageable and I am not trying to stay out of the cupboards all day and also ensuring I am getting the nutrition I need to actually recover. I like to keep things simple and use the formulas from above every day regardless of training as it all balances out at the end of the week.
GET FAMILY AND FRIENDS ON BOARD
My wife recently went on a ketogenic diet after a recommendation from her best friend - also a physician and board certified in nutrition. The reason was two-fold - weight loss and an elimination diet to see if she was sensitive to gluten, dairy, etc. This prompted a change in lifestyle in our home that helped me with my nutrition goals. All of the junk was out of the house and replaced with lean protein and low carb vegetables. I could eat all meals with my wife as it is hard to argue with lean protein and vegetables as being good food choices. I just needed to add in some more carbohydrates to support my energy demands with training. It is much easier to stick to sound nutrition when your friends and family are also supportive of your goals. It is not uncommon for some friends and family to pressure us into 'living' and 'loosening up'. I just shrug it off - how can someone that cares about me make fun of trying to be healthy? If I was complaining about not being able to eat certain things or trying to convince others to live like we do, then that would be another story. Eat the birthday cake and enjoy a champagne toast with friends and family as those are enjoyable things that make life richer. Just keep things in moderation. Extremes one way or the other seem to be the problem areas.
TAKE THE LONG VIEW
By this, I mean to try and be patient and give things time before changing anything. 2 weeks is generally a good starting point to see if the changes you implemented are working. Keep in mind, it is not just weight from day to day as water retention due to fatigue from a big weekend of riding might lead to a 5 pound weight gain on the scale Monday morning. Look at the trends, how your clothes fit, how you look in the mirror and how you feel. One can also track body fat to note trends. Careful with this one as calipers and BF scales at home are not very accurate and influenced by hydration. I think you will know if you are heading in the right direction if you are honest with yourself. I'd rather be 158 pounds and feeling strong heading into the hilly race than 154, dehydrated and depleted. True change takes time and I believe it is what we do the majority of the time day to day that leads to results. I do not believe there are any legal short cuts to improved performance and body composition changes and the long view is needed.
BE HONEST AND EASY ON YOURSELF
Eating disorders are very common in endurance sports and something I take seriously. I know athletes that are obsessed over losing that last 2 pounds but cannot seem to get it off so are always 'dieting'. 2 pounds is not likely to have an impact on performance either way, so maybe let that one go as your weight will likely vary 2 pounds between breakfast and lunch. Same goes with some athletes saying they just cannot lose the weight and they have 15-20 pounds that could be shed healthily. If this is you and you are happy in your skin and lifestyle, then by all means keep the 15-20 pounds, but if you are interested in improving your performance against others that are doing the things to be 15-20 pounds leaner, then making some gradual and healthy changes will help you with your goals. If you like ice cream, then eat ice cream and you can still reach your nutrition goals if you are on track most of the time. Cutting out things we like or being hard on ourselves tends to have the opposite effect over time and life is too short to deprive ourselves of some simple pleasures as long as we use moderation.