Nutrition and its role in exercise
Nutrition plays a huge role in how well you can perform when exercising. This role varies between different sports and activities, but there are some general rules to follow.
The General Rules
Make sure you include enough complete protein, complex carbs, fat and vitamins and minerals in your diet to get all your essential nutrients. On top of this, drinking enough fluids will help you reach your full potential, so there's no need to be afraid of calories!
Remember: As you demand more from your body, your body demands more from what you eat and drink.
Planning your day effectively sets you on the road to recovery. Eating a nutritious meal within the hour of your workout and getting a good night's sleep are 2 top tips for making the most of your time. You may have heard conflicting information on whether a plant-based diet is good or bad for exercise performance. The answer is neither, overall diet quality is the important part. Think about your diet as a whole, rather than trying to eat food that fits into a specific group, such as low fat or avoiding artificial sweeteners.
Contents
Nutrition requirements for exercise
Protein
Protein is the first macronutrient (a nutrient we need in the diet in large amounts) that comes to mind when exercise is mentioned. When exercising, especially weight training, muscle is essentially torn and needs reconstructing[1]. To build muscle, the body requires amino acids, which are the units that make up proteins. The body can’t produce 9 essential amino acids, so we need to get them from our diet. Take a look at our Guide to Protein for more information.
Carbohydrate
Carbohydrate often gets a bad name, but it’s an important macro. Amongst other uses, it spares protein to carry out its other jobs (like repairing muscles) other than providing energy[2]. Have a look at our Why Carbs Aren’t Bad article. Carbohydrates are stored as glycogen in the body. During anaerobic exercise, such as sprinting and weight lifting, the body uses carbohydrate, and if that runs out, protein[4]. During aerobic exercise, such as swimming or walking, if the glycogen stores run low, this is when you feel tired[3].
Fat
Similarly to carbs, fat is often seen negatively. Fat is actually the most calorie dense macronutrient, so it’s a great source of energy. Give our Good Fats and Bad Fats article a read for more information.
Why protein isn’t everything when you’re trying to get fit
When there’s not enough carbohydrate in the diet, the body starts to use protein as fuel after exercise[5]. This means there’s less protein available for recovery, which can hinder results[5]. If you’ve heard of carb loading, this is where the idea fits in, it ensures the body has enough fuel so performance isn’t affected, particularly for endurance athletes[6]. The more you exercise, the more carbohydrate you need[7].
Vitamins and Minerals
Vitamins and minerals, or micronutrients, are also key. Micronutrients have functions throughout the day, from training to sleeping. For example, B vitamins help the body to use the nutrients from food for energy, while zinc is involved in reconstructing tissue[8, 9].
Drinking plenty of water
Drinking enough fluids is also important. Water helps with digestion, regulating body temperature and circulation, transporting nutrients and oxygen to cells, removing waste products, and providing lubrication and cushioning to joints[10].
When we exercise we produce heat, and sweating is a way to cool down. A loss of 2% body weight in fluid can seriously impair the ability to do muscular work[11], so it’s crucial to sip water, not just during exercise, but regularly throughout the day.
Nutrition requirements for recovery
Calorie intake
As you increase your exercise levels, your body’s demand for certain nutrients also increases[9]. Your body will require more energy so up goes your calorie needs.
Micronutrients
When you sweat you lose fluids and electrolytes, such as sodium, potassium and chloride[12]. Stay hydrated throughout the day, and, as well as consuming foods, electrolytes can also be topped up with sports drinks.
Folate and vitamin B12 are vital for proper red blood cell functioning which deliver nutrients to cells[13, 14]. Iron ensures that red blood cells can transport oxygen effectively, so a lack of iron can lead to tiredness[15]. Calcium and vitamin D help maintain bone health and reduce the risk of fractures[16].
Exercise recovery
Sleeping and recovery are one and the same. Sleep gives the body time to start restoration processes[17]. Tryptophan, and magnesium regulate the sleep hormone melatonin[18]. Not getting enough could lead to poorer quality sleep and consequently a slower recovery[18].
The time you eat is key
Correct fuelling for a workout is important. Have a small meal, which includes carbs, about an hour before a session. However, the most crucial time to effectively fuel for a workout is after your previous workout. Have a protein and carbohydrate based meal within the hour after a training session[19,20].
Nutrition to support different types of exercise
As there are so many ways to exercise, the easiest way to categorise is into aerobic (otherwise known as cardio) and strength training. Aerobic exercise is longer and more sustained, while strength training tends to involve intervals of intense exercise with the aim often being muscle growth.
Strength training and cardio
With strength training, eating protein from the right sources ensures you get all the amino acids you need. There is one essential amino acid that deserves a shout out; leucine. We need around 2.5g of leucine per meal in combination with other amino acids to kick start the building of muscle[21, 22]. You can make sure you’re getting enough by eating a meal with complete protein sources such as soy, or rice and beans.
For longer exercises, eating enough carbohydrates provides the energy required to prevent fatigue and help you to reach peak performance[23].
Eating a varied diet will provide all the nutrients your body needs. It’s best to aim for whole foods because most nutrients are more effective when eaten with others[24]. Absorption can depend on what else is eaten, for instance, fat soluble vitamins like vitamin D are better absorbed with fat[25]. Read our How Well are the Vitamins and Minerals in Huel Absorbed article for more information.
What role does plant-based eating play?
There has been a lot of talk recently about whether a plant-based diet is better for performance and that people who didn’t consume meat couldn’t reach their full exercise potential. A plant-based diet is neither better or worse for exercise performance than an omnivorous or a heavy meat based diet[26]. It’s the overall quality of the diet that is key[26, 27]. For instance, a diet lacking calcium and vitamin D, whether it includes meat or not, will lead to poorer bone health. Where the benefits of a plant-based diet come in is environmental impact. For example, plant sources can produce as much as eight times more protein for the same carbon emissions as animal sources[28]. Take a look at our How to Eat More Plant-based Foods article for more information.
A plant-based diet can also increase diet quality through an increase in fibre and a lowering of saturated fat[29, 30]. It can be nutrient-dense, but it’s likely that a vitamin B12 supplement will be required. Read more on the 26 Essential Vitamins and Minerals article.
References
Schoenfeld BJ. Does Exercise-Induced Muscle Damage Play a Role in Skeletal Muscle Hypertrophy? The Journal of Strength & Conditioning Research. 2012; 26(5):1441-53.
Ivy J. Regulation of Muscle Glycogen Repletion, Muscle Protein Synthesis and Repair Following Exercise. J Sports Sci Med. 2004; 3:131-8.
Jensen J, et al. The Role of Skeletal Muscle Glycogen Breakdown for Regulation of Insulin Sensitivity by Exercise. Frontiers in physiology. 2011; 2:112.
Peric R, et al. Fat Utilization During High-Intensity Exercise: When Does It End? Sports Medicine - Open. 2016; 2:1-6.
Rustad P, et al. Intake of Protein Plus Carbohydrate during the First Two Hours after Exhaustive Cycling Improves Performance the following Day. PLoS One. 2016; 11:e0153229.
Ormsbee M, et al. Pre-Exercise Nutrition: The Role of Macronutrients, Modified Starches and Supplements on Metabolism and Endurance Performance. Nutrients. 2014; 6:1782-808.
Foundation BN. Nutrition for sport and exercise. Date Accessed: 15/12/20. [Available from:
]
Prasad AS. Zinc: an overview. Nutrition. 1995; 11(1 Suppl):93-9.
Woolf K, et al. B-vitamins and exercise: does exercise alter requirements? International journal of sport nutrition and exercise metabolism. 2006; 16(5):453-84.
Jéquier E, et al. Water as an essential nutrient: the physiological basis of hydration. European Journal of Clinical Nutrition. 2010; 64(2):115-23.
Sawka MN, et al. American College of Sports Medicine position stand. Exercise and fluid replacement. Med Sci Sports Exerc. 2007; 39(2):377-90.
Maughan RJ. Fluid and electrolyte loss and replacement in exercise. Journal of sports sciences. 1991; 9 Spec No:117-42.
MedlinePlus. Folic acid in the diet. Date Accessed: 15/12/20. [Available from:
https://medlineplus.gov/ency/article/002408.htm
]
NIH. Vitamin B12. Date Accessed: 15/12/20. [Available from:
https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/
]
NHS. Iron. Date Accessed: 15/12/20. [Available from:
https://www.nhs.uk/conditions/vitamins-and-minerals/iron/
]
McCabe MP, et al. Current concept review: vitamin D and stress fractures. Foot Ankle Int. 2012; 33(6):526-33.
Breen L, et al. Leucine: a nutrient 'trigger' for muscle anabolism, but what more? J Physiol. 2012; 590(9):2065-6.
Norton LE, et al. Leucine regulates translation initiation of protein synthesis in skeletal muscle after exercise. J Nutr. 2006; 136(2):533s-7s.
Kerksick C, et al. International Society of Sports Nutrition position stand: nutrient timing. J Int Soc Sports Nutr. 2008; 5:17.
Poole C, et al. The role of post-exercise nutrient administration on muscle protein synthesis and glycogen synthesis. J Sports Sci Med. 2010; 9(3):354-63.
Dl S, et al. Leucine: Considerations about the Effects of Supplementation. Journal of Nutrition and Health Sciences. 2015; 1.
Stock MS, et al. The effects of adding leucine to pre and postexercise carbohydrate beverages on acute muscle recovery from resistance training. Journal of strength and conditioning research. 2010; 24(8):2211-9.
Coyle EF, et al. Muscle glycogen utilization during prolonged strenuous exercise when fed carbohydrate. J Appl Physiol (1985). 1986; 61(1):165-72.
van Vliet S, et al. Achieving Optimal Post-Exercise Muscle Protein Remodeling in Physically Active Adults through Whole Food Consumption. Nutrients. 2018; 10:224.
Dawson-Hughes B, et al. Dietary fat increases vitamin D-3 absorption. J Acad Nutr Diet. 2015; 115(2):225-30.
Lynch H, et al. Plant-Based Diets: Considerations for Environmental Impact, Protein Quality, and Exercise Performance. Nutrients. 2018; 10:1841.
Kanter M. High-Quality Carbohydrates and Physical Performance: Expert Panel Report. Nutr Today. 2018; 53(1):35-9.
Gardner CD, et al. Maximizing the intersection of human health and the health of the environment with regard to the amount and type of protein produced and consumed in the United States. Nutrition Reviews. 2019; 77(4):197-215.
Clarys P, et al. Comparison of nutritional quality of the vegan, vegetarian, semi-vegetarian, pesco-vegetarian and omnivorous diet. Nutrients. 2014; 6(3):1318-32.
Parker HW, et al. Diet quality of vegetarian diets compared with nonvegetarian diets: a systematic review. Nutr Rev. 2019; 77(3):144-60.
