Supplements: Separating Science from Fiction

by | Aug 2, 2018 | Performance Blog


what science says about sports nutrition

In the field of sports and performance, one of the most discussed topics is supplements. The interest in sports supplements is fuelled by athletes attempting to perform to their highest potential, fighting for every inch they can. Supplement companies have recognized this, and many have a multitude of offerings within their product line, each claiming performance enhancing effects. This leads to confusion and poses questions such as: What are they? Where do they come from? What do they do? Which are beneficial? Which are worth spending money on? What amount of each should I take? Are they safe?


Protein is one of three main macronutrients, with carbohydrates and fats being the remaining two. Protein has many roles in the body, but it is mainly known for muscle building & repair in the sports world. Protein powder comes in many forms and from various sources, with the most common being whey. Whey is a protein found in milk along with another protein called casein. During the process of cheese making, whey is removed and is processed into the supplement form you are familiar with. Other forms of protein powder include soy, egg, and hemp proteins.

The World Health Organization’s (WHO) recommendation for protein intake is 0.8 g/kg/d (grams of protein per kilogram of bodyweight per day). However, in athletes this is increased due to increased muscle mass and an intake of 1.3-1.8 g/kg/d is required to maximize muscle protein synthesis. Ideally, this level of protein intake should be supplied by whole foods such as meats and legumes, as foods contain more vitamins and minerals than protein powders. However, in cases where you cannot meet this level of protein intake, protein powders can be a useful tool to help you get there. The optimal protein intake following exercise to enhance muscle protein synthesis is in servings of between 20-30g. This protein can be sourced through whole foods such as meat/fish/eggs or through protein powders.


If you find that using a protein powder would be helpful for you, it’s important to buy the right one. Protein powders are not cheap and can cost upwards of $15/lb so its important to consider if it is feasible and whether it is worth the added cost for the small potential performance improvement. Some protein powders have high quantities of fillers and sugars to improve taste and texture. Therefore, when purchasing, it is important to look at the nutrition facts and ingredients to ensure there aren’t unnecessary levels of additives.


Branched chain amino acids (BCAAs) are one of the most popular supplements available currently. Amino acids linked in long chains form proteins. There are 22 amino acids in total, with three being identified as BCAAs due to their chemical structure, these are; leucine, isoleucine, and valine. Our bodies are not able to make all of the amino acids, including the BCAAs and therefore they must be sourced through one’s diet. Protein rich foods such as meats and legumes when digested are broken down into amino acids including BCAAs.

Leucine is important for activating muscle protein synthesis, and when ingested past a certain threshold, triggers a muscle growth/repair response. However, they are not necessary to supplement, despite what many supplement companies may claim. The research has shown that if your diet is sufficiently high in protein (>1.1 g/kg/d) you do not need to supplement with BCAAs as you ingest enough. In fact, doing so will just burn a hole in your pocket, with the price of BCAAs costing more than $40 for just 30 servings. Nonetheless, if you feel like spending a bit of extra cash, BCAAs are not dangerous for consumption and will not decrease your performance; they won’t necessarily increase it either. A great food alternative to induce the muscle protein synthesis response post workout or throughout the day is milk, due to its high BCAA content.


Caffeine is the world’s most consumed central nervous system (CNS) stimulant and is abused/utilized daily by millions of people worldwide. Our CNS is part of the nervous system involving the brain and spinal cord. Caffeine has the ability to affect the CNS through its interactions with your adenosine receptors. Adenosine is a substance which can induce a state of drowsiness when it binds to its receptor. Caffeine has the ability to block this receptor, preventing the feeling of drowsiness which it is well known for. Caffeine can be found in coffee, tea, soda, chocolate, multivitamins, and many other commonly consumed products.

Caffeine receives a lot of attention in mainstream media and the messages can often be conflicting. As a performance enhancer, caffeine can be effective, providing what feels like a boost of energy from around 30 minutes until 3-4 hours following consumption. It is most effective in longer endurance events than in shorter exercise durations (8-20 mins) and is negligible in sprint events. Individuals who do not consume caffeine regularly, such as those who don’t drink coffee, gain more of an advantage when supplementing caffeine than those who have a tolerance to caffeine from repeated exposure. The amount of caffeine needed for these benefits is around 3-9 mg/kg consumed around one hour before exercise. A widely spread myth about caffeine is that it may be dehydrating; this is untrue. Research shows that caffeine does not have dehydrating effects when taken before exercise (1).

Everyone responds to caffeine differently, and just because your teammate or training buddy gains an increase in performance with it, it does not mean you will. You may find yourself with an upset stomach, nauseated, or anxious. There are many ways to consume caffeine, such as coffee, energy gels, pre-workouts, and caffeine tablets. Different people prefer different methods of supplementation but the main thing to remember is if you’re considering supplementing with caffeine then the best way to approach is through trial and error; find out what type and how much, if any, works for you. Some people perform better without it, so don’t assume you need to use it!


Creatine is an organic substance that can be produced in the body through the metabolism of two amino acids or found in protein-rich foods such as meat and fish. Dietary sources of creatine are relatively limited in regard to the quantity they provide, which is why supplementation of creatine has become popular, but what is it and does it have any performance enhancing effects?

Creatine is utilised in the body to aid the synthesis of adenosine triphosphate (ATP). ATP is the bodies main source of energy and is used to fuel muscle contraction and hence exercise. Creatine also plays a role in the contraction of skeletal muscles, again due to its interaction with ATP. Without the presence of creatine, your bodies muscle would be fatigued, but this does not mean supplementation is necessary as we synthesize adequate amounts daily.

Research in oral creatine supplementation has shown that supplementation increases creatine levels within our muscle fibres leading to an increase in the work capacity they are capable of. In addition, supplementation of creatine has been shown to increase the energy output in short bouts of exercise and decrease concentrations of lactic acid when compared to individuals who did not supplement creatine (2). The effective level of creatine supplementation for these effects lies between 3-8 g/d.

As outlined above, creatine definitely has some performance enhancing effects, and isn’t overly expensive, with a 500g tub that contains one hundred 5g servings costing around $17. Creatine can be found in many forms such as powders, capsules and tablets, they all result in the same outcome so if you’re considering supplementing creatine then pick which works best for you.

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  1. Graham TE. Caffeine and exercise: metabolism, endurance and performance. Sports Med. 2001;31(11):785-807.

2. Hall M, Trojian TH. Creatine supplementation. Curr Sports Med Rep. 2013;12(4):240-4.


BSc Human Nutrition

Brionn found a passion for nutrition and fitness through the many sports he played growing up. He pursued this passion by studying for a bachelor of science in human nutrition from University College Dublin, Ireland. Following graduation he moved to Halifax to play rugby where he met the Onside community and quickly put his education into practice.

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OnSide Performance Centre
Office: (902) 404 – 5647
110 Chain Lake Dr., Unit 3D
Halifax, NS
B3S 1A9

Get the latest training tips