Any triathlete who has some respect for himself ( as French would say) tries to undertake a competition (M, Half, Ironman …), whether major or secondary, in the best physical, physiological and mental conditions. This, in order to get to the best performance on effort, often correlated with optimal individual performance.
It is also logical that feeding on ironman (or on LD) is different than the one during a preparation on a sprint. The type of effort is different, the training also and therefore the diet must be adapted bearing in mind these factors.
Eating while preparing a triathlon, the most common mistakes are :
- A poorly organized and unstructured diet, including skipped meals (worries about schedules, availability …) => poor planning of meals,
- Too much decrease in food intake, often associated with limitation of lipid (fat) intake,
- A deficiency in the intake of vitamins and minerals (sodium, magnesium, potassium, calcium …) in relation to the needs arising from sport,
- A repetitive menu, with a lack of variety in the choice of foods consumed,
- An hydration often neglected and poorly organized (cf. home made drinks).
Every individual is unique, there is no standard model for everyone!
Dietetic must be adapted to every individual according to :
- the triathlete: age, sex, height,% fat mass (MG), medical record, …
- the type of activity (sprint vs Ironman!),
- the degree of intensity (competition / leisure), and the volume,
- the frequency of training sessions, competitions,
- his usual rhythm of life (family, professional …), his tastes, his habits …
- and all the factors inherent in his or her life. !!
Preparing a competition is often referred to as “physical preparation”, “race management”, “mental preparation”, but very rarely (or never) “nutritional or dietary preparation”. The latter concept generally refers to the principle of “OVERCOMPENSATION”, identical to a bodybuilding program, which is defined as an objective for any athlete in order to achieve a performance. The principle is theoretically simple and consists in finding the ratio volume / intensity / training frequency allowing to increase the physical and physiological capacities session after session => the energy reserves are reconstituted to a level higher than the initial one. Rest, sleep and relaxation are key parameters and are an integral part of this “construction process”.
On the whole, the main objectives of the triathletes before approaching a major competition are to prevent vitamin and mineral deficits, avoid any digestive disorder, guarantee optimal hydration and of course have an optimal content of muscle and liver glycogen (ie, glucose stores in muscles and liver).
Glycogen gradually releases these glucose molecules into the bloodstream in order to maintain blood sugar levels and to meet the needs of the body (vital organs, muscles … but also the brain! ).
Nutrition offers several solutions to the preparation of a race, different theories can be adopted during the week preceding the race. Nevertheless, these different theories have mostly been tested in sportsmen of other specialties and a special dietary form emerges. It was realized that by adopting a high carbohydrate diet the days before physical activity increased glycogen stocks and improved exercise yield.
Food intake during the week before the race
Scandinavian dissociated diet
It takes place during the 6 days prior to the race, popular among sport professionals, but also among the amateur community, whose objective is to obtain a glycogen level (glucose reserve or “sugars”) particularly high at the time of the race. This is commonly referred to as “glycogenic overcompensation”. This diet, although effective to increase glycogenic reserves, is nevertheless not free of side effects: weight loss, digestive disorders, fatigue, diarrhea, hypoglycemia, mood disorders, see the article I dedicate to it.
Two phases are present:
- A first period lasting for 3 days (precisely from D-6 to D-4) where the diet is low in carbohydrates (hypoglucid phase, below 20% of total energy intake (AET) whereas the normality must be over 50% AET) and rich in lipids-proteins. In parallel, an intense sporting activity is practiced in order to cause a maximum reduction of glycogen reserves, especially muscular.
- A second period, on the contrary, rich in carbohydrates (it is referred to as hyperglucid phase,> 80% AET), normoprotein and hypolipid, associated with a very significant reduction of the training, even some rest.
Important note: drink plenty of water between meals during these two phases, a minimum 2L. to be adapted individually.
Dissociated modified diet
So, I recommend the Modified Dissociated Diet (or RDM) much better tolerated and ensuring a “glycogenic overcompensation”. In this diet, the food intake from D-6 to D-4 is slightly hypoglucidic (40 to 50% of the Total Energy Intake) and the diet of D-3 to the D-Day is hyperglucidic (> 70% of the Energy Intake Total) as in the RDS. I give more details in the article specifically devoted it.
A shorter form can be adopted, depending on the specific constraints specific to each runner, eliminating the first phase and keeping only the second phase, which can be extended by one day, ie 4 days. We will discuss the latter in this article.
It should be remembered that this phase, which is essential in this process of increasing “energy reserves”, operates in synergy with a specific training program.
RDM in theory
Several basic parameters must be respected!
Remind the athlete of the objectives of these 3 (or 4 ) pre-competitive days
- Ensure the formation of optimal energy reserves (glycogen);
- Guarantee a perfect condition of the muscle tissue and prepare a good recovery;
- Avoid digestive problems: food choices in general and individualized.
Insist for thriathlete on the interest of high glycogen stocks:
- Long-term efforts (long-distance triathlon): these glycogen stocks determine the duration during which a high rate can be maintained => Notion of Capacity.
- Shorter efforts (Sprint triathlon ): these glycogen stocks condition the ability to spend a lot of energy at every moment => Notion of Power.
Explain the main factors influencing the level of glycogen stocks
- The initial state of the stocks in question knowing that a muscle fiber “empty in glycogen” will pump more “sugar”: this is called “Overcompensation”.
- The level of training: the more one is trained, the better the ability to store (in particular by better sensitivity to insulin).
- Diet: a diet rich in carbohydrates promotes glycogen re-synthesis especially in the first hours after exercise (8-12g / kg / d). Benefit from the metabolic lapses occasioned during the last training, often qualitative (lightened in intensity), in order to optimize your glycogen reserves.
Finally, very important
Never lose sight of the fact that hydration should be important and increased compared to usual: minimum 2L (67.6 fl oz) ! 1g (0.03 oz) of glycogen is stored with 2.7g of water!
Sports Dietitian Nutritionist