Nutrition basics for sport

Where do we get our energy from to power us through sport? 

Our energy comes from our 3 main macronutrients:

-       Protein

-       Carbohydrate

-       Fat

For each 1g of protein and carbohydrate, we will get 4 kcal.  For 1g of fat, we get 9 kcal.

Energy from these macronutrients comes from the chemical bonds that bind together either the protein, carbohydrate or fat.  As the bonds are carefully broken, the chemical energy created as they break is stored as ATP which is released to create energy. 

How many calories do we need?

This is very individual and depends on your basal metabolic rate (BMR).  BMR is the number of calories that you burn at rest just to keep yourself alive.  This accounts for a whopping 60-75% of the calories that you burn.  You can use a BMR calculator (just google this online) to work out your individual needs.

You then can work out your daily calorie need by multiplying your BMR by the level of physical activity.

BUT…and this is a big but!  BMR is quite a crude way of measuring but also the calorie of one food isn’t necessarily equal to a calorie of another food.  How you eat, what you eat with a food, your ability to absorb foods will all affect output of that calorie.  Individual requirements are subject to genetics, metabolism, age, size, muscle mass, body composition and importantly your personal goals.

Your macronutrients

1.     Carbohydrates

Carbohydrate is the preferred energy fuel for muscles but also your brain, nervous system and heart.  Muscles will always choose carbohydrates for fuel if it is available.  Any carbohydrate that is consumed is broken down into glucose which your body will use for energy.  Any excess that the body does not use will be stored in the liver and muscle initially but beyond that is stored as fat. 

Future blogs will cover the pros and cons of high or low carb diets and the type of carbohydrates you should be prioritising.   

2.     Protein

Protein is formed by a chain of amino acids.  Some of these are made by the body but nine amino acids we have to get from our diet and are known as essential amino acids.  Protein is vital for growth, formation and repair of cells including muscle and bones.  Protein also make enzymes, hormones, antibodies, neurotransmitters and controls fluid balance.  It can be used as fuel in the absence of carbohydrate or fat. 

Our individual need for protein is varied.  The recommended daily allowance is 0.8g/kg of body weight.  However, regular exercisers will need more than this to repair damaged muscle cells or to build new muscle cells.  As a minimum, you should look for 20g of protein per meal alongside protein rich snacks. 

3.     Fat

In the absence of carbohydrate our body will use fat for fuel.  Fat is fundamental to our health since is makes up all our membranes of every cell in our body.  We need fat to be able to absorb and transport fat-soluble vitamins – A, D, E and K.  Cholesterol is the precursor to all our sex and steroid hormones.  Fat is satiating and will aid digestion.  There are various types of fat including saturated, trans, monounsaturated and polyunsaturated.  Omega 3 and omega 6 fats are essential fats that we have to get from the diet.  The ratio of omega 3 to omega 6 is vital for optimal health.  I will talk specifically about different fats, the best sources and the benefits in future blogs. 

Alongside your macronutrients, it is vital to consume a varied diet to ensure you are optimising your micronutrients too.  Micronutrients are your vitamins, minerals and antioxidants that are all vital for exercise.  We must not forget the importance of hydrating too.  Water is vital to all cells and it enables reaction in the body to take place including energy production.

I hope this has given you a basic understanding of nutrition and I look forward to delving deeper into your macros, micros and other nutrients each month!