Questions and answers

1During the days preceding the competition

How can you prepare for a competition through diet?

2In many sports, performance relies on prolonged effort (triathlon, marathon) or on the repetition of high-intensity efforts (team sports). In these circumstances, a decrease in carbohydrate levels in the liver and/or active muscles can lead to the appearance of fatigue and decreased cognitive and muscle performance. This extensive solicitation of glycogen stores must be prepared for, in nutritional terms, over the two days preceding any competition. However, for sports relying on brief efforts, repeated only a few times (sprints, jumps, throws, etc.) this type of strategy does not appear very useful.

What dietary strategies can be adopted to increase the body’s carbohydrate reserves before a competition?

3A consensus has now been reached that a carbohydrate ration of 10 to 12 g.kg⁻¹.d⁻¹ over 36 to 48 hours is sufficient to load-up muscle glycogen stores in trained male athletes. However, it is important not to neglect hydration as water is required to convert carbohydrate to glycogen. Some studies have shown that muscle glycogen storage can be increased by half, or even doubled, when the carbohydrate intake is increased over one to four days. These levels could significantly enhance performance during a competition.

4Even though it has been shown that, during exercise, women are more sparing with their carbohydrate stores than men, their capacity to increase their glycogen muscle reserves through a high-carbohydrate diet is identical to men’s. In athletes who tend to put on weight, it is recommended that this carbohydrate-rich diet (10 to 12 g.kg⁻¹.d⁻¹) be strictly limited to the 36 hours preceding the competition.

Does adopting a low-sugar diet before the high-carbohydrate period promote increased glycogen storage?

5During the 1970s, Scandinavian studies showed that intramuscular glycogen stores increase after a one-week food-combining diet. This involved three or four days of intense training associated with a low-carbohydrate diet, followed by three to four days of recovery with a high-carbohydrate intake. The results of this study showed a significant increase in aerobic performance in those following this kind of diet, compared to the test group which maintained normal eating patterns. For a long time, these studies were accepted, and a food-combining diet before competition (the most famous of which is the “Scandinavian dissociated diet”) was thought to increase performance levels. Since then, this conclusion has been widely reviewed, and has been contradicted by various studies involving trained athletes. Indeed, the most recent studies show that in trained athletes, glycogen stores could be increased without the low-carbohydrate diet phase preceding the high-carbohydrate period. In this population, increasing carbohydrate intake over 48 hours appears to be enough to generate the levels required on the day of the competition.

What mistakes should be avoided when applying a high-carbohydrate pre-competition diet?

6Some studies have shown that some athletes have difficulty increasing their carbohydrate reserves before a competition. This can be explained by a certain number of classical “mistakes”:

• It is quite common to see athletes who continue to train intensely until the last days before a competition. To build up glycogen stores, a preparation period must be observed during which training intensity is reduced.

• Many athletes do not increase their carbohydrate consumption enough. We must help them to understand what constitutes a daily ration of 10 to 12 g of carbohydrate per kilo of body weight per day. For this, individual follow-up by a dietician would be ideal to ensure the best strategy is implemented.

• To reach the target carbohydrate amount, fibre-rich foods should be limited as these favour satiety and can cause digestive disorders. During the two days of increased carbohydrate intake, athletes should increase their consumption of energy drinks, honey, white pasta, white bread, etc.

• The increase in calorie intake with a view to promoting loading of muscle glycogen stores is generally associated with an increase in body mass, which can be up to 2 kg. This is due to the increase in endogenous glycogen storage and to an increase in the contribution of water to body weight. For some athletes, this weight gain (which is favourable to performance in disciplines where glycogen stores are significantly reduced during events) might not be easy to accept, or could even cause the athlete to stop following the diet. It is thus essential to explain that this weight gain will have a positive effect on their performance during the competition.

• Some athletes use the high-carbohydrate period as a pretext to increase their calorie intake without adhering to the structured diet plan. It is important to explain that this type of dietary strategy is only beneficial if food intake is controlled. Indeed, increasing lipid intake mainly favours an increase in fat mass, slows down carbohydrate assimilation and makes it difficult to reach a carbohydrate ration of 10 to 12 g.kg⁻¹.d⁻¹. To avoid this, it is recommended that foods rich in carbohydrates but low in fat be consumed over the two days of the high-carbohydrate diet.

• In order to be stored in the muscles, the carbohydrates ingested must be associated with water molecules. It is thus essential that water intake also be increased during the two days over which the high-carbohydrate diet is followed to optimize glycogen storage mechanisms. The simplest indicator that you are drinking enough is to check the colour of your urine, which should remain clear.

7The day of the competition

When and how to eat before a competition

8Eating before a competition allows you to achieve a better performance level than when you compete on an empty stomach. However, it should be remembered that most of the glycogen stores required during the event are constituted over the two days preceding the event. Therefore, it is preferable to avoid hearty meals on the day of the competition. The pre-competition meal should prepare the athlete to compete unhindered by the digestive process. In this context, we can give several recommendations regarding the pre-competition meal and snack:

• drink enough to maintain a good hydration status;

• limit fatty foods and foods rich in fibres to favour gastric emptying and reduce the risk of gastrointestinal problems;

• consume a moderate amount of protein, but avoid red meat;

• favour foods rich in carbohydrates to maintain blood sugar (cereals, pasta, rice, etc.);

• adapt calorie intake depending on the time between the meal and the competition: if this is less than three hours, reduce the amount of food to be consumed.

9Beyond these general recommendations, the characteristics of the pre-competition meal should be tailored to individual specificities. Some, for instance, are happy to eat large amounts of food up to two hours before a competition, while others will prefer a light meal which limits gastrointestinal problems. It is therefore recommended that various nutritional strategies be tested during training to identify the one best adapted to each athlete’s individual characteristics.

Should food with a low glycaemic index be favoured?

10Foods rich in carbohydrates can generate different reactions in terms of blood sugar levels: those with a low glycaemic index generate a slow and prolonged rise in blood sugar levels, whereas those with a high glycaemic index trigger a rapid but short-lived blood sugar peak. For the last pre-competition meal, it has been suggest that it is preferable to eat foods with a low glycaemic index. However, research has not validated this hypothesis. Indeed, several studies showed that consuming carbohydrates during the event (as an energy drink, for example) is enough to maintain blood sugar levels, thus reducing the impact of the type of carbohydrates eaten during the pre-competition meal. Finally, since foods with a low glycaemic index generally contain a high proportion of fibre, their consumption can increase the prevalence of intestinal problems during the competition. Under these circumstances, it is recommended that foods with a medium to high glycaemic index be included in the last meal before the competition, and that carbohydrate intake be maintained during the competition itself (with an energy drink), in order to limit gastrointestinal problems.

What strategies should be adopted if you are too nervous to eat before the competition?

11Even though it is clear that athletes perform better when they are well hydrated and have sufficient energy stores, some competitors have difficulty eating before an event due to stress. To avoid this problem, substitution strategies are recommended, where athletes consume meal substitutes, which are easily assimilated and digestible. Planning small snacks such as cereal bars or energy bars up to one hour before the competition will allow an adequate nutritional intake, without requiring a large intake in the form of a pre-competition meal. Whatever the case, not eating at all before the event is never the right strategy.

Before the competition, is it useful to have a drink while waiting?

12Athletes who eat three hours before the beginning of a competition might need drink between finishing their meal and the start of the event. This is particularly important for athletes who have difficulties eating during the last meal before the competition. In addition to curbing appetites, pre-competition stress consumes energy. Under these circumstances, fructose appears to be the most appropriate sugar to consume. Right from the beginning of the warm-up, the athlete should be provided with a drink containing appropriate amounts of fructose and glucose. Solid food (biscuits, gingerbread, cereal bars, yoghurts, ripe fruit) intake is fine up to this point if the athlete tolerates it, but should be stopped at the start of the warm-up because there would not be time to digest it before the start of the competition. It is best not to drink sodas (such as Red Bull) as energy drinks, because their high sugar content triggers significant variations in blood sugar levels, leading to reactive hypoglycaemia, which hinders performance.

Does training at altitude modify athletes’ eating habits?

13Most of the studies investigating how athletes’ eating habits change during training at altitude or mountaineering show that there are modifications. Thus, at high altitude, athletes tend to reduce their food intake. This “altitude anorexia” is the main reason why weight loss is almost systematically observed after extended periods at altitude. While the reduction in body mass is mainly linked to a loss of fat mass, long-term perturbation of the energy balance can also lead to decreased muscle synthesis and increased protein oxidation during exercise. This can, ultimately, lead to reduced muscle mass. To fight against this phenomenon and maintain performance levels, it is recommended that athletes be encouraged to increase their spontaneous food intake, and to ensure that they maintain their muscle mass during the period spent at altitude. This can be helped by planning regular maximum strength tests.

Why is it essential to maintain a high carbohydrate intake when training at altitude?

14Beyond the spontaneous reduction of food intake, several studies have shown that altitude also modifies how the energy used during exercise is resynthesized. The main effect of this is an increase in the use of muscle glycogen stores. This greater dependence on carbohydrates during exercise could balance the decrease in partial oxygen pressure in the air by favouring the use of an energy substrate which provides a greater ATP yield for a given amount of oxygen (i. e. compared to a similar amount of lipids). This hypothesis is reinforced by the observation that lipid stores are slightly less prone to depletion during exercise at altitude compared to a reference situation at sea level. Even if this greater solicitation of sugar metabolism seems to diminish in the medium term in acclimatized athletes, it remains significant, even after several weeks at altitude. This adaptation appears to be beneficial in terms of energy production, but it accelerates the decrease in muscle glycogen stores during intense training sessions. In terms of nutrition, carbohydrate intake must therefore be increased during training at altitude. Thus, the Acceptable Macronutrient Distribution Range should be adjusted so that 60% of total calories are provided by carbohydrates. Favouring a high-carbohydrate diet will limit protein oxidation, thus reducing the risk of altitude-related muscle loss. Given the spontaneous tendency of athletes to reduce their daily calorie intake when at altitude, implementation of a nutritional plan could be extremely beneficial. This will involve using the post-exercise table as far as possible and adapting timing of sugar intake (see Fact sheet No. 1 Energy recovery, p. 235). In the context of a particularly intense training course at altitude, consuming a high-carbohydrate diet for the two days before departure will help to limit the risk of muscle glycogen depletion, which can lead to a decrease in the athlete’s training capacity (see Fact sheet No. 3 Competition, p. 258).

Practical applications

1. The days before a competition

Basic recommendations

15› Maintain a balanced diet while making sure you have an adequate carbohydrate intake:

16Increase your intake of starchy food during meals (pasta, rice, potatoes [boiled/steamed/mashed], bread)

17Reduce your intake of snacks betweens meals and fatty foods (chocolate bars, crisps, fast food, etc.)

18› Reduce your intake of foods that you have trouble digesting (defined according to personal tolerance):

19› Do not test any new sports foods/products. Do tests during training periods

20› Make sure you are well hydrated

21► Example of a balanced diet on the day before a competition

For some sports

22Increasing muscular carbohydrate reserves can be beneficial.

23► Sports for which this is the case

24› Sports requiring continuous exercise of average to high intensity lasting longer than 1.5 hours (marathon, middle-to long-distance triathlon, cycling, etc.)

25► Avantages and disadvantages

26› Each athlete must weigh up the pros and cons:

27► How to do it

28 Avoid using this method during a competition if you have not previously tested it during a training period.

29› When: the last two days before a competition (a day and a half for women)

30› How: do not increase the size of meals, but have three meals and three snacks (morning, afternoon and evening)

31› Which foods: favour low-fibre, low-fat foods which are rich in carbohydrates (sweet drinks, energy bars, yoghurt drinks, fruit jellies, baguette, jam, honey, pasta, rice, etc.)

32› In addition:
–avoid training too much during this period,
–stay well hydrated.

33► Example of a high-carbohydrate day (10 to 11 g/kg of body weight) for an athlete weighing 70 kg

2. On the day of the competition (if only one event during the day)

34 It is essential to eat in the few hours preceding the event (a meal [A] about 3 hours before, or a snack [B] up to 1.5 hours before).

A The last meal before the event (ideally 3 to 4 hours before)

35› Above all, should be easy to digest, rich in carbohydrates and contain little fat

36OR

B A snack (1.5 hours to 2 hours before the event)

37› Foods which are light and easily digestible should be chosen

38› Make sure you are well hydrated

39 1 hour before the event

40› If you are anxious, take a drink (containing fructose) while waiting

41› From the beginning of the warm-up, you can start drinking your sports drink (a few sips every 15 to 20 minutes)

42 During the event

43► Priority: hydration

44 At the end of the event

45► Main objective

46› Recovery (essential if the competition continues the next day). (See Fact sheet No. 1 Energy recovery, p. 235)

In practice

47› Eat as soon as possible

48› The meal should be balanced and rich in carbohydrates

49› If the meal is to be eaten more than 30 minutes after the end of training, it is recommended that you have a snack in the meantime

3. On the day of the competition (if there are several events during the day)

50 2 to 3 hours before the first event

51► One last meal or snack before the event (ideally about 3 hours before)

52› Above all, whatever you eat must be easily digestible, rich in carbohydrates, low in fat and contain a source of proteins if lunch is likely to be light

53› Make sure you are well hydrated

54 Between 2 events

55► Foods recommended based on time available

56Tips!

57After eating sweet products, drink some water to rinse your mouth to avoid the risk of developing cavities. Don’t forget salty foods (sports drinks/foods), because one often tires of a sweet taste.

58 After the last event

59► Main objectives

60› Recovery (essential if the competition continues the next day) (See Factsheet No. 1 Energy recovery, p. 235)

61› Compensate for the day’s imbalances (especially if you did not have a real meal for lunch)

In practice

62› Eat as soon as possible

63› The meal should be balanced and rich in carbohydrates

64› If the meal is to be eaten more than 30 minutes after the end of the event, it is recommended that you have a snack in the meantime

Recipe

Gingerbread

65Serves 4

66Preparation time: 20 minutes

67Cooking time: 35 minutes

68Difficulty:

69Ingredients

70■ 75 ml semi-skimmed milk

71■ 150 g pine honey

72■ 100 g rye flour

73■ 50 g plain flour

74■ 10 g baking powder

75■ 2 eggs

76■ 30 g granulated sugar

77■ 1 teaspoon ground cinnamon

78■ Half a teaspoon grated nutmeg

79■ Half a teaspoon anise powder

80■ 5 g vanilla extract

81■ Zest of 1 lemon

82■ Zest of 1 orange

83Sift the wheat flour and baking powder together.

84Mix the eggs and sugar. Heat the honey to 50 °C, add to the egg mixture and stir well.

85Add the spices, vanilla extract and citrus zests.

86Stir in the flour mixture.

87Then add the rye flour and warm milk.

88Pour into a tin and bake at 160 °C for 35 minutes.

89Turn out and wrap the warm cake in clingwrap.

90Chef’s note

91This cake is very rich in carbohydrates and is easily digestible. It can be eaten before a competion (from the day before to up to 1 hour before), between two events (separated by at least 2 hours) or immediately after the end of a competition.

92Wrapping the cake in clingwrap while it is still warm will allow it to keep for 12 days without loss of flavour or properties.

93Very useful for competitions takeing place over several days or abroad.

94Nutritional analysis per person