Exercise Nutrition

Daily Dietary Intake

The energy we have for our daily activities is derived from the foods and drinks that we consume. These consist of macronutrients (carbohydrates, protein, and fats) and micronutrients (vitamins and minerals). The focus here will be on the macronutrients.

The Institute of Medicine (1) recommends that our daily dietary intake consists of 45–65% carbohydrates, 10–35% protein, and 20–35% fat. This is to maintain health and is for the general population. Your daily intake requirements may differ depending on your level of physical activity.

Carbohydrates and protein both contain 4 kilocalories (kcals) per gram, whereas fat contains 9 kcals per gram. Each kcal equates to 4.184 kilojoules (KJ) of energy. Therefore, each gram of carbohydrate and protein is equivalent to 16.74 KJ of energy and one gram of fat equates to 37.66 KJ (2).

 

 

Individual Energy Requirements

Energy requirements are different for everyone and depend on an individuals basal metabolic rate (BMR) and their physical activity level (PAL). BMR represents the rate of energy use in order to maintain resting bodily functions such as breathing, heartbeat, keeping warm. For most individuals, this is 1.1 kcal per minute (2). BMR may be calculated using the following formula (3):

BMR for Men = (10 x weight in kg) + (6.25 x height in cm) – (5 x age) + 5

BMR for Women = (10 x weight in kg) + (6.25 x height in cm) – (5 x age) - 161

 

PAL rates range from 1.4–1.9, where 1.4 represents a very low level of physical activity such as work or leisure time; 1.6 for women and 1.7 for men represents moderate intensity levels of physical activity; and 1.8 for women and 1.9 for men represents high levels of physical activity (2). Energy expenditure is calculated using the following formula:

Energy expenditure = BMR x PAL

 

Macronutrient Recommendations for Physically Active People

Carbohydrates

Carbohydrates are the main source of energy. Carbohydrate sources include fruit and vegetables, rice, and cereals. Table 1 is a good guide and based on different level of psychical activity (4):

 

 

Table 1: Recommended Daily Carbohydrate Intake by Physical Activity Level

Activity		Recommended Carbohydrate Intake Per Day
Low	Low intensity	3-5 g/kg body weight
Moderate	Moderate intensity (e.g., 1 hour per day)	5-7 g/kg body weight
High	Endurance training, 1-3 hours per day at moderate-high intensity	6-10 g/kg body weight
Very high	4-5 hours per days at moderate to high intensity	8-12 g/kg body weight

 

 

Table 2 provides fueling strategies for various exercise situations (4).

Table 2: Carbohydrate Fueling Strategies.

Fuelling Strategy	Exercise Duration	Recommended Carbohydrate Intake	Examples of Carbohydrate Sources
General fuelling	Less than 90 minutes	7-12 g/kg/day	Carbohydrate-rich sources, low fiber, easily consumed for gut comfort
Carbohydrate loading	More than 90 minutes of continuous exercise	10-12 g/kg/day starting 36-48 hours before event	Small regular snacks
Fast refuelling	Less than 8 hours of recovery before next demanding event	1-1.2 g/kg for the first 4 hours, then resume daily carbohydrate needs	Carbohydrate-rich foods and drink
Pre-event fuelling	Before exercise of more than 60 minutes	1-4 g/kg, 1-4 hours before exercise	Carbohydrate-rich foods and drinks of preference and practicality
During brief exercise	Less than 45 minutes	Not required	-
During sustained high intensity exercise	45-75 minutes	Small amounts including mouth rinse	Carbohydrate drinks and snacks that are convenient to consume. Products with glucose and fructose mixtures are a good choice.
During endurance or stop and start events	1-2.5 hours	30-60 g/hour
During ultra-endurance exercise	More than 2.5 hours	Up to 90 g/hour

 

 

Protein

Protein helps grow and repair muscle tissue. Protein requirements range from 1.2-2.0 g/kg/day. For an optimal response, it’s best to 10 g of protein during the early recovery stage which is 0-2 hours post exercise. Muscle adaptation as a response to training can be enhanced by consuming 0.3 g/kg every 3-5 hours post exercise. Endurance athletes should aim for 1.2-1.7 g/k/day and resistance trainers should ingest 1.6-1.8 g/kg/day, bodybuilders may consume up to 2.0 g/kg/day (4). Sources of protein include poultry, meat, eggs, cheese, milk, soybeans, , chickpeas and pulses (legumes, lentils).

 

 

Fat

Many people may think that fat is bad, but fat is an essential part of our diet. Fat provides energy and is essential for the facilitation of fat-soluble vitamins (A, D, E and K). We should try to limit our intake of saturated fats (4) – those that are solid at room temperature (red meat, butter, palm and coconut oils, cheese). Saturated fats are problematic in terms of weight gain and heart disease risk, so we should limit these and include sources of essential fatty acids. Essential fatty acids are based on linoleic acid, the omega-6 group; and alpha-linolenic acid, omega-3 group (5). Essential fatty acids are found in fish and shellfish, leafy vegetables, olive oil, soya oil, walnuts, and various seeds such as flaxseed, chia, pumpkin, rapeseed, and hemp.

 

 

For a quick tasty energy fix, you might like to try these Healthy Chocolate Coconut Balls

© Sporty Types

1. Institute of Medicine. (2005). Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids.Retrieved from https://www.nap.edu/read/10490/chapter/1
2. Baum, J.I., Rodibaugh, R., & Mitchell, C. (2015). Energy expenditure and weight management. Retrieved from  https://www.uaex.edu/publications/pdf/FSFCS94.pdf
3. Diabetes.co.uk. (2019). BMR Calculator. Retrieved from https://www.diabetes.co.uk/bmr-calculator.html
4. American College of Sports Medicine. (2016). Nutrition and Athletic Performance. Medicine and Science in Sports and Exercise, 48(3), 543-568. doi:10.1249/MSS.0000000000000852
5. Di Pasquale, M.G. (2009). The essentials of essential fatty acids. Journal of Dietary supplements, 6(2), 143-161. doi:10.1080/19390210902861841