Part two of our article on tips to guide your sports nutrition choices. We had previously discussed the main general principles for deciphering nutritional labelling and defining a sports profile. We will now focus on the criteria that should guide your choices according to the different types of products (before, during and after exercise).
Before exercise, stabilize energy reserves and balance the body
The purpose of waiting drinks or exercise preparation drinks is to provide the energy that will supply the body with energy for the first few minutes of exercise. First of all, it is important to note that traditional « cures of malto » do not replace exercise preparation drinks. These cures to be carried out several days before the event are more and more contested. Indeed, maltodextrins are complex carbohydrates that are certainly very effective during exercise but their overconsumption, giving the illusion of having filled up with energy, can quickly prove problematic because of their complexity to be metabolized by the body (digestive disorders, stomach aches…). We can only recommend « natural cures » through a diet slightly enriched in carbohydrates.
In any case, and whatever the method, these energy reserves that we spend time building are fragile. The hours and minutes before the start of a race, the start of a match is very energy consuming. Stress, trampling, warm-up, the body quickly nibbles at the available energy stock, even before the effort has begun. That is why it is important to use exercise preparation products. They will have several actions:
- Hydrate the body properly: favor drinks or snacks with water. In theory, it is necessary to consume about 500mL in the hour before the beginning of the effort in order to start properly hydrated.
- Provide energy quickly available: first reflex, look at the nutritional analysis table to find out the amount of carbohydrates provided per dose. We recommend products that contain between 20 and 30g of total carbohydrates. Step two, identify carbohydrate sources. To do this, refer to the list of ingredients that will mention the carbohydrates present in order of importance. For these types of products, we recommend carbohydrate combinations, especially maltodextrin. Coupling different sources of carbohydrates makes it possible to cover needs in the more or less long term.
- Rebalance the body by providing vitamins and minerals that facilitate the use of carbohydrates and anticipate losses related to perspiration during exercise
- Avoid the presence of antioxidants before exercise (Vitamin C, Vitamin E, zinc…) at the risk of them turning into pro-oxidants during exercise
- Choose a few relevant ingredients such as glutamine, which promotes cellular hydration and will help to fulfil the desired function of optimal hydration before exercise. To counter the effects of stress, you can also check that there is an association between vitamin B6 and magnesium in sufficient quantity (>10% of NRVs*).
During effort, provide energy and compensate for losses
It is more difficult to systematize the compositions of a nutritional product for exercise. Everything depends on the support you consider and there are many of them: gels, ready-to-use drinks to reconstitute, energy bars, fruit pastes, sweet or savoury snacks… Each of them can provide different sources of nutrients with different functions depending on the type of effort. We will focus here on the priority contributions valid for all effort specificities and on some more specific ingredients.
- Energy intake: it is mainly in the form of carbohydrates. To compensate for the energy costs related to exercise, it is important to provide between 30 and 60g of carbohydrates per hour of exercise. There is no need to go further, the body is able to oxidize only 60g of energetic substrate. By overdosing carbohydrates, some products will cause the opposite effect of the desired one, namely reactive hypoglycemia and/or gastrointestinal disorders. Concerning sources, it is also important that a product consists of different types of carbohydrates: sucrose, fructose (in limited quantities because they are more difficult to digest), maltodextrins, various syrups (glucose, rice, etc.). Combinations of 2 or 3 carbohydrate sources are the most relevant. Refer to the list of ingredients to identify them.
- Hydration: essential, essential if we do not want to risk the phenomenon of dehydration. It is recommended to drink 500 to 600mL per hour of effort. Beverages to be reconstituted or ready to use have the advantage of fulfilling this function. For other energy sources (gels, bars, fruit jellies, snacks), it is important to supplement their consumption with a regular supply of water.
- Mineral intake: some minerals are essential to fight against the losses contained in sweat and thus prevent dehydration, cramps and muscle pain. Among them, sodium, potassium, magnesium. Dosages of about 25% of NRVs are relevant since it should not be forgotten that when multiplying the catches, it is very easy to reach 100% of the NRVs. Be careful with products « too rich » in minerals (same for vitamins). Intakes of calcium, iron, zinc, copper can also be interesting in addition. Sometimes, labels do not accurately detail sodium intake. To find it easily, you will find in the nutritional analysis table of the packaging a line identified « salt ». This is the intake of Sodium Chloride, well known since it is our table salt. To convert it to sodium, simply divide its value by 2.54. For example, if a product mentions 1.5g of salt per dose, this is equivalent to 1.5/2.54 = 0.59g of sodium, i.e. 590mg.
- Vitamin intake: B-group vitamins are essential during exercise. They facilitate the assimilation and use of carbohydrates by the body. Among them, vitamin B1 must be systematically present. Vitamins B2, B3 and B6 are also important. Antioxidant vitamins can also be interesting as long as they are not overdosed. Vitamin C and vitamin E are useful to the body during exercise below 20% to 25% of the NRVs*. In the event of over-consumption of so-called « antioxidant » products during exercise, the body risks transforming them into « pro-oxidants », or quite the opposite. Finally, when making your choice, also take into account seasonality. Indeed, products containing vitamin D can be particularly suitable in winter, since the risk of deficiencies is much higher because of the reduction in sunshine weather.
- Proteins and other ingredients: for endurance efforts in particular, you can choose energy products that contain proteins. Vegetable proteins are recommended for their ease of assimilation. You can also find whey proteins (from milk) and in particular BCAA (Branched Amino Acids) which can be useful during exercise.
- Other ingredients such as citrulline or beet juice powder also have positive effects on performance. Several clinical studies have shown excellent results with these active ingredients.
After the effort, replenish the stocks and regenerate the organism
There are many recovery products, but they do not all effectively address this problem, which has many components. Importantly, do not forget that the recovery products should be used as soon as possible after the end of the effort (ideally within 20 minutes).
- Restoring energy reserves: there is nothing more effective than carbohydrates to do this. The most effective combination to look for in the list of ingredients is as follows: Maltodextrin, sucrose, fructose. It is this mix that has shown the best effects on recovery. In terms of quantities, 20 to 25g of carbohydrates per dose are recommended.
- Regenerate muscle fibres: for this, proteins are essential. Whether they are vegetable (rice, soya, pea protein, etc.) or animal (milk protein). 10 to 15g of protein per dose are recommended for significant effects on muscle fibre reconstruction. Among these proteins, BCAAs are essential and in particular Leucine.
- Redo the stocks of vitamins and minerals: in the first instance, the vitamins will facilitate the assimilation of the other ingredients (in particular those of the B group). Antioxidant vitamins (C&E) are relevant here to combat oxidative stress generated by stress. Finally, vitamin D is recommended during winter exercise. Dosages from 50% to 100% of the NRVs* are justified in recovery. For minerals, the objective will be to compensate for sweat losses related to effort. Sodium, Potassium, Magnesium, Calcium, Iron, Zinc, Copper all have roles to play. Their dosage can also range from 50 to 100% of the NRVs*. Importantly, drinks that provide certain minerals via bicarbonate sources will be even more effective, since bicarbonates will counter muscle acidity.
- Other elements are obviously very relevant:
- Beta Carotene can play a role as a complementary antioxidant for example.
- Vitamins B9 and B12 work on muscle oxygenation and stimulation of the immune system.
- Creatine and HMB (beta-Hydroxy-beta-MethylButyrate) will promote recovery by limiting damage at the cellular level,
- Citrulline will stimulate protein resynthesis during recovery,
- Plant extracts (green tea, ginkgo bilobé, turmeric…) can be interesting in terms of inflammatory mechanisms and the elimination of waste caused by stress.
- This list could be supplemented by many active ingredients that are the subject of clinical studies.
As you can see, many parameters are taken into account when it comes to choosing the nutritional products that best match your profile. By respecting these few general principles, you will ensure that you use products that are effective in terms of their composition. It is obvious that other criteria can guide your choices (packaging, convenience, taste, price).
* % of Nutrient Reference Values [UE regulation No 1169/2011]
Julien RAOUX, Labs Nutrition