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Macronutrients Intake of Top Level Cyclists During Continuous Competition - Change in the Feeding Pattern

Authors:
  • Unidad Regional de Medicina Deportiva and Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain.

Abstract

In order to quantify the nutritional status and the feeding pattern of professional cyclists during continuous competition, food intake was accurately measured and recorded using the weighed inventory of food (over three 24 h periods) during all meals in ten top professional cyclists during a real 3 weeks' competition. A 24 h period was defined as the time between the start of one stage and the next start. The 24 h period intake of energy, protein, fat, and carbohydrate was used to discover whether these intakes met requirements for endurance exercise. The average intake of energy and macronutrients was: energy = 23.5 +/- 1.8 MJ/24 h period, carbohydrate = 841.4 +/- 66.2 g/ 24h period; protein = 201.8 +/- 17.7g/24 h period; and fat = 158.6 +/- 16.3 g/24 h period. The carbohydrate, protein and fat contribution to energy was 60.0%, 14.5%, and 25.5% respectively. Fluid intake per 24h period was 3.29 +/- 0.94l (1.26 +/- 0.55 l during the race). Our study shows a similar energy intake in comparison with the only previous study in 1989 but there is a change in the feeding pattern of top level cyclists. A more important role is given to the intake of carbohydrate just after competitions together with an increase in protein intake. Both changes could have a positive effect on performance.
... Os esportistas são os praticantes de exercícios físicos visando à saúde e melhoria na qualidade de vida, respeitando os limites de cada um e de forma que não interfiram na rotina diária. Os atletas são aquele que praticam atividades de alto rendimento ou ultra rendimento, os exercícios são extremamente específicos com maior volume e intensidade, para de fato aumentar o rendimento, tendo necessidades nutricionais maiores, dentre outros aspectos (GARCIA-ROVÉS et al.,1998). ...
... As recomendações dietéticas oficiais para indivíduos que pratiquem atividade física moderada ou intensa sugerem uma ingestão elevada de carboidratos, uma vez que aumentar a disponibilidade de carboidratos infere em aumento do rendimento durante as rotinas de atividades (COSTILL;WILMORE, 1999). ParaGarcia-Rovés et al. (1998) eCostill e Wilmore (1999), o consumo recomendado é de 7 a 10g de carboidrato a cada quilo de massa corpórea, ao dia, ou que pelo menos perfaça 60% da ingestão calórica diária, formando assim a base da alimentação do indivíduo, seja ele praticante ou não de atividade física e independente do grau da atividade.A ingestão proteica diária, para muitos órgãos internacionais, é de 0,8g/kg de massa corporal ao dia (EDEN;ABERNETHY, 1994). Contudo, novas pesquisas, com praticantes de atividades físicas, trouxeram essa recomendação à tela da discussão, uma vez que tais indivíduos necessitariam de um aporte maior de proteínas, sendo diferente para cada tipo de atividade, buscando garantir uma melhor performance e saúde, sem lhe causar danos KATCH, 1994;McARDLE et al., 2001).Para McArdle e Katch(1994) a ingestão proteica, para os esportistas, deve variar de 1,2g/kg a 1,8g/kg, levando em consideração a atividade executada, percebendo os mesmos em estudo que ao consumir mais de 2g/kg diariamente, não havia alteração da condição física e rendimento do indivíduo.Em relação ao consumo de lipídeos, a Sociedade Brasileira de Alimentação e Nutrição, recomenda a ingestão diária de 20% a 25% do valor calórico total. ...
... Previous reports have indicated that endurance athletes generally consume more protein than thought to be required (Tarnopolsky, 2004). This high protein intake has been reported previously in other studies, with cyclists showing similar results to the present study with a protein intake of 3.0 ± 0.3 g/kg BM/day in the Tour of Andalusia (Sánchez-Muñoz et al., 2016); 2.9 ± 0.3 g/kg BM/ day in the Tour of Southland (Rehrer et al., 2010); 3.0 ± 0.3 g/kg BM/day in the Tour of Spain (García-Roves et al., 1998); or 2.5 g/kg BM/day in the Tour of France . The cyclist's fat intake was slightly lower than the current recommendations (from 20% to 35% of total energy intake) for athletes (Rodríguez et al., 2009). ...
... Similar results have been reported during the Tour of Southland (Rehrer et al., 2010) and during a 24-h cyclist team relay race (Bescós et al., 2012) where fat constituted just 17.3% and 17.4% of the total energy intake, respectively. However, a high percentage of fat intake has also been reported in the Tour of Andalusia (23.2 ± 1.7%; Sánchez-Muñoz et al., 2016), Tour of France (23%; Saris et al., 1989), and the Tour of Spain (25%; García-Roves et al., 1998). ...
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The aim of this study was to quantify the food intake of an International Cyclist Union (UCI) World Tour professional cyclist team and to analyse changes in body composition during the Tour of Spain. Nine male professional road cyclists (31.3 ± 3.0 years) volunteered to participate in the study. Nutritional data were collected each day throughout the 3-week Tour by two trained investigators who weighed the food ingested by the cyclists. Mean nutritional intake of the cyclists was as follows: carbohydrate, 12.5 ± 1.8 g/kg/day of body weight (BW) (65.0 ± 5.9%); fat, 1.5 ± 0.5 g/kg/day BW (17.9 ± 5.6%); and protein, 3.3 ± 0.3 g/kg/day BW (17.1 ± 1.6%). Intake of all micronutrients, except for folate, vitamin D and potassium (which were 78.7%, 46% and 84% of Recommended Dietary Allowances (RDA), respectively), exceeded the RDA. Height, weight, skinfolds, circumferences and diameters were taken following the guidelines outlined by the International Society for the Advancement of Kinanthropometry. Body density, body fat percentage, muscle mass, total muscle mass and fat mass of the arms and thighs were calculated. Percentage body fat, fat mass and upper arm fat mass significantly decreased (p < .05) after the Tour independent of the equation method used in the calculations. Total muscle mass remained unchanged. Generally, this sample of cyclists consumed more protein and less fat than the recommended amount and had low weight, BMI and fat mass. It is suggested that sports nutritionists design personalised diets in order to maintain a correct proportion of nutrients as well as controlling possible anthropometrical changes that could affect performance.
... Furthermore, peloton traditions such as allowing periods within a race in which riders can eat without their competitors "attacking" and designating domestique riders to ferry food/drink supplies to the team leader also promote energy intake. Such features might explain the consistency of reports from stage races in which professional cyclists are observed to consume high mean daily intakes of energy [5600-6000 kcal (23-25 MJ)] and CHO [12-13 g/kg BM] to achieve a remarkably close match of TDEE, with impressive proportions of daily EA consumed while racing [108,132,133]. Obviously, whether these reports of EB found during racing can be matched during daily high-volume training situations in cycling and other sports, where athletes tend to be much less professionally supported, remain to be fully elucidated. ...
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The symptom similarities between training-overload (with or without an Overtraining Syndrome (OTS) diagnosis) and Relative Energy Deficiency in Sport (RED-S) are significant, with both initiating from a hypothalamic–pituitary origin, that can be influenced by low carbohydrate (CHO) and energy availability (EA). In this narrative review we wish to showcase that many of the negative outcomes of training-overload (with, or without an OTS diagnosis) may be primarily due to misdiagnosed under-fueling, or RED-S, via low EA and/or low CHO availability. Accordingly, we undertook an analysis of training-overload/OTS type studies that have also collected and analyzed for energy intake (EI), CHO, exercise energy expenditure (EEE) and/or EA. Eighteen of the 21 studies (86%) that met our criteria showed indications of an EA decrease or difference between two cohorts within a given study (n = 14 studies) or CHO availability decrease (n = 4 studies) during the training-overload/OTS period, resulting in both training-overload/OTS and RED-S symptom outcomes compared to control conditions. Furthermore, we demonstrate significantly similar symptom overlaps across much of the OTS (n = 57 studies) and RED-S/Female Athlete Triad (n = 88 studies) literature. It is important to note that the prevention of under-recovery is multi-factorial, but many aspects are based around EA and CHO availability. Herein we have demonstrated that OTS and RED-S have many shared pathways, symptoms, and diagnostic complexities. Substantial attention is required to increase the knowledge and awareness of RED-S, and to enhance the diagnostic accuracy of both OTS and RED-S, to allow clinicians to more accurately exclude LEA/RED-S from OTS diagnoses.
... Subsequently, there were several reasons why such an unwarranted emphasis was placed on protein during the period following World War II. In the early 20th century, the medical view of the potential health benefits of a vegetarian diet tended to be unenthusiastic (Gale et al., 2007). As late as 1939, the nutritionist J. S. McLester proposed the idea that the consumption of huge amounts of animal protein (far in excess of current recommendations) was responsible for the accomplishments of Western countries (Mangels et al., 2011, p. 66). ...
Chapter
Technology-supported food development is an important aspect of modern societies. At the same time, there is a strong trend towards natural and whole plant-food diets as practicable tools to be implemented in everyday life. In ancient times, gladiators and prominent philosophers already knew that plant-based diets (vegetarian, vegan) lead to peak performance. This chapter presents data on a highly underestimated body of evidence-based scientific information, still mostly neglected by nutrition science, and provides a more basic but dual approach to food bio-engineering and human development. This comprehensive overview of vegetarian and vegan diets ranges from the myths about meat and early studies into the effect of vegetarian diets on sports, through the flood of studies published on the health-threatening effects of foods from animal sources, to current studies showing the benefits of of predominantly plant-based diets on human health and sports performance, but without claim of completeness. What does this chapter add?  This chapter reminds of the fact that vegan diets not only supply all nutrients in adequate amounts (except for vitamin B12), but has enabled recreational as well as professional athletes to achieve top performances in their chosen disciplines. How might this impact daily dietary practice?  The knowledge about the benefits of a vegan diet on mental and physical performance can motivate conventional consumers to change to some kind of vegetarian diet, which would be beneficial, in addition to health, also to the environment, the climate and animal welfare.
... In light of this finding, it is suggested that cyclists consider the role of indoor training to practice and optimise individual CHO intake while heeding nutrition recommendations, with the understanding that self-made CHO supplementation is a suitable strategy if required [21,25]. Where cyclists consumed some CHO during exercise, consumption in the present study is in line with professional cyclists' intake during a stage of the Vuelta A Espana [26], that is, notably lower than current guidelines. However, data from the 1989 Tour de France indicate professional cyclists can and do meet 90 g.h -1 targets if required to [27]. ...
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Purpose To assess energy and carbohydrate availability and changes in blood hormones in 6 professional male cyclists over multiple single-day races. Methods We collected weighed food records, powermeter data and morning body mass across 8 days. Carbohydrate intakes were compared to contemporary guidelines. Energy availability (EA) was calculated as energy intake minus exercise energy expenditure, relative to fat-free mas (FFM). Skinfold thickness and blood metabolic and reproductive hormones were measured pre- and post-study. Statistical significance was defined as p≤0.05. Results BM (p=0.11) or skinfold thickness (p=0.75) did not change across time, despite alternate-day low EA (14±9 vs 57±10 kcal·kg FFM·d ⁻¹ , race vs rest days, respectively; p<0.001). Cyclists with extremely low EA on race days (<10 kcal·kg FFM·d ⁻¹ ; n=2) experienced a trend towards decreased testosterone (-14%) and insulin-like growth-factor-1 (-25%), despite high EA (>46 kcal·kg FFM·d ⁻¹ ) on days in-between. Carbohydrate intakes were significantly higher on race vs rest days (10.7±1.3 vs 6.4±0.8 g·kg·d ⁻¹ , respectively;p<0.001). The cyclists reached contemporary pre-race fueling targets (3.4±0.7 g·kg·3h ⁻¹ carbohydrates; p=0.24), while the execution of CHO guidelines during race (51±9 g·h ⁻¹ ; p=0.048) and within acute (1.6±0.5 g·kg·3h ⁻¹ ; p=0.002) and prolonged (7.4±1.0 g·kg·24h ⁻¹ ; p=0.002) post-race recovery was poor. Conclusions We are the first to report day-by-day periodization of energy and carbohydrate in a small sample of professional cyclists. We have also examined the logistics of conducting a field study under stressful conditions in which major cooperation of subjects and team management is needed. Our commentary around these challenges and possible solutions is a major novelty of the paper.
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Aside from the limits imposed by heredity and the physical improvements associated with training, no factor plays a bigger role in exercise performance than does nutrition. Since the mid-1930s, dietary carbohydrate (CHO) has been known to enhance performance, particularly during prolonged exercise. In these early studies, respiratory gas exchange of oxygen and carbon dioxide exchange was first used to demonstrate that during intense exercise CHO serves as the primary fuel for the muscles. It was also observed that when subjects were fed diets rich in CHO they tended to have greater endurance and to derive more of their energy from CHO during steady-state exercise. The mechanisms underlying this shift toward CHO oxidation and enhanced performance have only recently been examined using the invasive measurements of muscle and liver glycogen and the employment of isotopes. The following review will attempt to show the important role played by endogenous and ingested CHO during muscle performance. Specific attention will be given to the influence of dietary sugar on muscle and liver glycogen storage.
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The effect of forced liquid (L) or solid (S) carbohydrate (CHO)-rich feedings on plasma glucose, insulin, and glycogenesis after glycogen depletion was investigated. The relationship between glycogen restoration and maximal physical working capacity (MPWC) was studied as well. Eight males performed two experiments, with 2 weeks interval, on a bicycle ergometer. In each experiment, MPWC was determined in a graded test, which was immediately followed by interval work until exhaustion. After exercise cessation (EC), the subjects started to consume a standardized amount of concentrated L or CHO-rich food. Insulin and glucose concentration in blood were determined. Muscle glycogen was determined before, immediately after, 5 h after, and 22 h after EC. MPWC was determined again 22 h after EC. Four subjects performed a third experiment, in which solid food consumption was left ad libitum (AL). A rapid glycogen repletion was found 5 h after EC, i.e., from 72 +/- 40 to 198 +/- 38 mmol/kg in the S, and from 69 +/- 39 to 192 +/- 40 mmol/kg in the L experiment. The higher plasma glucose and insulin levels (P less than 0.05) during the 5 h after EC in the S experiments did not elicit a difference in glycogen repletion. Glycogen synthesis rate in the AL experiment was lower (P less than 0.05) than in the L and S experiments. Glycogen restoration in the L and S experiments was complete 22 h after depletion. However, despite repletion of glycogen, MPWC was decreased (P less than 0.05) in both experiments.(ABSTRACT TRUNCATED AT 250 WORDS)