Sports Nutrition Basics

I find it helpful to review these sports nutrition basics before the race season begins or a change in seasons.

The Institute of Medicine of National Academies recommends the acceptable macronutrient distribution ranges for adults (as a percentage of calories) as follows:
- Carbohydrate: 45 - 65% 
- Fat: 20 - 35% 
- Protein: 10 - 35%
This nutrition distribution means that a good portion of one’s plate should consist of whole grains, vegetables and fruit, nuts, beans with some relatively smaller amounts of poultry, eggs, fish, or red meat.

Carbohydrates = Fuel
Of the three macronutrients, carbohydrates provide the most easily accessible source of energy for our muscle glycogen stores. Two types of sugars provide runners with this source of energy. The easiest sugar to break down is the monosaccharide, found in foods like fruit, fruit juice, vegetables, and honey. And chains of monosaccharides go into making the polysaccharide, found in foods like potatoes, corn, all grains and beans, and maltodextrin (in energy gels).

Glycemic index helps runners select foods that give a slow and small rise in blood glucose levels

For runners to keep in mind, any excess carbohydrate is stored in the liver for times when carbohydrates aren't as plentiful. And, beyond that, stored as body fat. Unfortunately, nutrition experts have sounded the alarm about health concerns resulting from an overconsumption of carbohydrates. Nevertheless, the Glycemic Index (GI) helps runners monitor and control the impact of carbohydrates on blood sugar levels. Like the diagram above illustrates, after eating a meal low on the GI, a slow and small rise in blood sugar level results as opposed to a quick and high response. When using this strategy, runners replace as many as possible foods identified as “High” on the GI in their diet with healthy lower GI alternatives. As well, runners can reduce the blood sugar impact of any food by pairing it with one that has a lower GI food, for example, covering waffles (high GI) with blueberries (low GI). Nevertheless, portion control is needed even if a lower GI strategy is followed as big meals no matter what they contain always stimulate a higher blood sugar response than smaller ones. 

This ATTACHED LIST ranks carbohydrates based on how much they raise blood sugar levels. Carbohydrates in the “Low” column are recommended to use most often, “Medium” use more often, and “High” less often. This is a list I refer to frequently and was developed by the Vancouver Coastal Health Authority in western Canada.

When training, best practice indicates that runners working at a 5K pace or faster will benefit from some pre-workout carbohydrate loading. Eating a carb-rich meal the night before or a snack shortly before a workout will help top up muscle glycogen stores.

For training runs or races lasting 70 minutes or more, best practice dictates runners should be fueling with 30 to 60 g of carbohydrate per hour. (With the more g of carbohydrate the runner can tolerate, the better for performance.) Below is a chart of some carbohydrate fuelling options for runners. When using these fueling options, it’s best to test in training first to see what works best for YOU, as needs and gastrointestinal reaction can vary. This year my plan is to fuel my workouts and races with natural sources of monosaccharides - honey and dates.

In sum, it's important to time the intake of carbohydrates around running - shortly before, during or after a run - runners can easily process both monosaccharide and polysaccharide sugars to replenish depleted glycogen stores in muscle fibers. The further in time the runner gets from when their run took place, that's when carbohydrate sources listed on the Glycemic Index as "Low" or "Medium" should be used more often than sources listed as "High".

Fats = Energy Storage
Fats (or more accurately, lipids) are important for energy storage, forming cell membranes (found in phospholipids), and forming hormones (in particular, steroid hormones). Foods like avocados, eggs, olive oil, nuts, and fish with omega-3 fats (e.g., salmon and sardines) are rich sources of fat.

The “hydrocarbon tail” found in fats is the site where energy is released. Base building runs at an easy intensity burn a good proportion of fats as energy. For instance, an easy run, with the purpose of developing the aerobic system, burns about 70% of calories from fats and 30% from carbohydrates, and brisk walking burns about 82% of calories from fat. However, when we increase running intensity to 10K pace, the energy profile shifts significantly to 18% of calories from fats and 82% from carbohydrates.

Steroid Hormones control and coordinate the chemical messaging for important bodily functions that runners quite frequently monitor: metabolism, inflammation, salt and water balance, and immune response to withstand illness and injury.

Protein = Construction 
While fat and carbohydrate have energy storage and fueling roles in running, protein provides the construction framework so we can access this energy and fuel. Made from sequences of amino acids, protein facilitates both aerobic and anaerobic energy production when running. For instance, hemoglobin is composed of protein for moving oxygen in the body during aerobic runs. And as runs increase in intensity, protein (or more accurately Monocarboxylate Transport Protein) is involved in shuttling of lactate and hydrogen ions from cells at this time (lactate shuttle). And after your run, protein is involved in growth and tissue repair.

Protein intake is important during the recovery window after training and racing. Research points to a 4 to 1 ratio of carbohydrates to protein. Many runners use chocolate milk as a recovery drink as it is close to this ratio.

Complete, Incomplete, and Combining Proteins - Complete protein contains all the essential amino acids in optimal proportions for supporting biological functions in your body. Animal-based foods like meat, poultry, fish, milk, eggs, and cheese are complete protein sources.
An incomplete protein, on the other hand, may be missing one or more of the essential amino acids, or it might just be low in them. Most plant-based sources of protein - like vegetables and grains - are incomplete.

Fortunately, the body can combine amino acids from two incomplete protein sources. The classic example of two incomplete protein sources combined together into a complete protein is rice and beans. Here are some other pairings:
-whole grain cereal with milk
-peanut butter on toast 
-hummus with whole wheat pita bread
-tofu with rice
-bean chili with bulgur (check out this winter chili recipe HERE)
-lentils with rice, corn, and/or whole wheat bread

As for protein needs, one source I consulted recommends 1.0 to 1.6 g of protein per kilogram (.45 to .72 g per pound) of body weight daily for endurance exercise. In comparison, this source recommends 1.6 to 2.0 g of protein per kilogram of body weight for strength and power exercise. So a person weighing 70 kilograms (155 lbs) needs about 91 g of protein daily for endurance exercise, whereas, 126 g of daily protein is needed for strength and power exercise.

In addition, recent research on masters athletes by Dr. Leigh Breen, an Assistant Professor of Musculoskeletal Physiology and Metabolism in the School of Sport, Exercise and Rehabilitation at the University of Birmingham indicated protein needs for masters athletes to be:
“From what we know we can come up with some broad guidelines for the master athlete. Master athletes nearing 50 should probably start with higher per meal protein intakes (0.4g/kg, 4-5 times daily). This certainly won’t be harmful and can only be beneficial. For individuals who find that tough to achieve and want to avoid supplements, an additional 1-2 servings of dairy with each meal (i.e. glass of fat-free milk and low-fat yogurt) or nuts/grains can be the difference. Pre-sleep protein is likely to be beneficial for Master athletes. It seems that Master athletes should aim for 40g of casein protein to maximize overnight synthesis rates, which is superior to 20g. Depending on the event the athlete is training for, it may mean cutting other macronutrients (fat and/or carbohydrate) in main meals to accommodate the extra protein. Master strength/power athletes should aim to reduce fat and carbohydrate intake marginally to accommodate the extra protein in order to maximize their power-to-weight ratio.”

While it would be a chore to measure grams of protein at each meal, I think it is a good idea to first take stock of one’s protein needs. And have a rough idea of how much protein is in some common foods found in the kitchen. For instance, an egg has 6 g of protein and a cup of milk has 9 g (with 7 g being casein protein). 
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Protein Ice Cream
Looking to get more protein into your diet? Try this Protein Ice Cream recipe.

Ingredients: 1 scoop protein powder of choice (chocolate flavor recommended) / 1 tablespoon almond butter or peanut butter / A few splashes of dairy or non-dairy milk of choice. The more watery/less thick it becomes.

Instructions: Stir the three ingredients together and place in the freezer for 30 minutes. (You can place in the fridge for pudding.)

This recipe has less than 300 calories and about 30 grams of protein. 
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Thanks for reading. 



Experiment of One Coaching covers topics ranging from running, strength training, health & wellness, sports nutrition to travel. I usually post once or twice a month.