This review summarizes results from studies investigating the physical characteristics, daily energy expenditures, diets, and effects of nutritional supplements to the habitual diets of soecer players. The results show that players fall within a wide range of stature and body weight, and they are classified as mesomorphs. The body fat of male players is about 10% of body weight, whereas the average for females is about 21%. Energy expenditure for males is about 4,000 kcal on training days and 3,800 keal on match day. while energy intake reported in other studies is on the order of 3,700 kcal. Carbohydrate (CHO), fat, and protein intakes are about 53,30, and 14% of energy intake, respectively, the remaining being from alcohol intake. There are indications that CHO supplements might be beneficial during soccer performance. However, more research is needed to clarity the importance of branched-chain amino acid and creatine supplementation in soccer.
Athletes, like all people, have special nutritional needs based on their age, lifestyle, health status, level of physical activity, physical conditioning, and type of sport. The diets of many athletes are inadequate due to overly restrictive eating habits, nutrition misinformation, dietary fads, and/or obsession with weight and food. There is a growing need for sports nutrition counseling and education to help athletes improve their eating habits. However, before attempting to develop intervention strategies, sports nutritionists should assess the metabolic changes that take place during exercise and how these changes affect nutrition status. In addition, it is important to consider how psychosocial factors may influence an athlete's eating habits and his/her ability to make positive changes. A two-pronged model is introduced that can be used as a guide for the practitioner in interpreting relevant data and integrating physiological and psychological considerations for the design of individualized nutrition care plans for athletes.
Dirk Aerenhouts, Jelle Van Cauwenberg, Jacques Remi Poortmans, Ronald Hauspie and Peter Clarys
This study aimed to estimate nitrogen balance and protein requirements in adolescent sprint athletes as a function of growth rate and physical development. Sixty adolescent sprint athletes were followed up biannually over a 2-yr period. Individual growth curves and age at peak height velocity were determined. Skeletal muscle mass (SMM) was estimated based on anthropometric measurements and fat mass was estimated by underwater densitometry. Seven-day diet and physical activity diaries were completed to estimate energy balance and protein intake. Nitrogen analysis of 24-hr urine samples collected on 1 weekday and 1 weekend day allowed calculation of nitrogen balance. Body height, weight, and SMM increased throughout the study period in both genders. Mean protein intakes were between 1.4 and 1.6 g kg−1 day−1 in both genders. A protein intake of 1.46 g kg−1 day−1 in girls and 1.35 g kg−1 day−1 in boys was needed to yield a positive nitrogen balance. This did not differ between participants during and after their growth spurt. None of the growth parameters was significantly related to nitrogen balance. It can be concluded that a mean protein intake around 1.5 g kg−1 day−1 was sufficient to stay in a positive nitrogen balance, even during periods of peak growth. Therefore, protein intake should not be enhanced in peak periods of linear or muscular growth.
Inge Spronk, Susan E. Heaney, Tania Prvan and Helen T. O’Connor
This study investigated the association between general nutrition knowledge and dietary quality in a convenience sample of athletes (> state level) recruited from four Australian State Sport Institutes. General nutrition knowledge was measured by the validated General Nutrition Knowledge Questionnaire and diet quality by an adapted version of the Australian Recommended Food Score (A-ARFS) calculated from food frequency questionnaire data. Analysis of variance and linear modeling were used to assess relationships between variables. Data: mean (Standard Deviation). A total of 101 athletes (Males: 37; Females: 64), 18.6 (4.6) years were recruited mainly from team sports (72.0%). Females scored higher than males for both nutrition knowledge (Females: 59.9%; Males: 55.6%; p = .017) and total A-ARFS (Females: 54.2% Males: 49.4%; p = .016). There was no significant influence of age, level of education, athletic caliber or team/individual sport participation on nutrition knowledge or total A-ARFS. However, athletes engaged in previous dietetic consultation had significantly higher nutrition knowledge (61.6% vs. 56.6%; p = .034) but not total A-ARFS (53.6% vs. 52.0%; p = .466). Nutrition knowledge was weakly but positively associated with total A-ARFS (r = .261, p= .008) and A-ARFS vegetable subgroup (r = .252, p = .024) independently explaining 6.8% and 5.1% of the variance respectively. Gender independently explained 5.6% of the variance in nutrition knowledge (p = .017) and 6.7% in total A-ARFS (p = .016). Higher nutrition knowledge and female gender were weakly but positively associated with better diet quality. Given the importance of nutrition to health and optimal sports performance, intervention to improve nutrition knowledge and healthy eating is recommended, especially for young male athletes.
Marina Nikić, Željko Pedišić, Zvonimir Šatalić, Saša Jakovljević and Danielle Venus
The aim of this study was to assess the nutrient intakes of elite junior basketball players in comparison with nonathletes.
A previously designed food frequency questionnaire was undertaken by 57 male elite junior basketball players 15 to 16 years of age and 53 nonathlete peers.
Mean estimated energy intake was more than 700 kcal higher in basketball players than in the nonathletes (p = .002). In both groups estimated energy intake was ~14% from protein, 38% from fat, and ~48% from carbohydrates. For the basketball players, estimated protein intake was below 1.4 g/kg in 32% of the group and above 1.7 g/kg in 51%, while carbohydrate intake was below 6 g/kg in 56%. Percentages of participants who apparently failed to meet the estimated average requirement for micronutrients were higher in the nonathlete group. The nutrients most likely to fail to meet the recommendations for nutrient density were vitamin A (~70%), zinc (49% in basketball players and 30% in nonathletes), niacin and calcium (~30% for both micronutrients in both groups).
Within the limitations of the survey methodology, elite junior basketball players appear to consume higher absolute energy, macronutrient and micronutrient intakes than nonathletes, but the contribution of macronutrients to daily energy intake and the nutrient density of food choices was similar for both groups. Elite junior basketball players might benefit from nutrition education targeting carbohydrate and protein intake. Dietary modifications that increase intakes of vitamin A, zinc, calcium and niacin in the diets of both groups might also be of value.
D. Enette Larson-Meyer, Kathleen Woolf and Louise Burke
relation to training is unlikely to achieve the full benefits of supplements geared at optimizing endurance or promoting muscle gain, respectively. A nutrition assessment is the first step in advising athletes on dietary strategies or supplement use. Nutrition assessment is the “systematic method for
Michael P. Corcoran, Miriam E. Nelson, Jennifer M. Sacheck, Kieran F. Reid, Dylan Kirn, Roger A. Fielding, Kenneth K.H. Chui and Sara C. Folta
activities as slow walking, household chores, or day-to-day tasks ( Hansen, Kolle, Dyrstad, Holme, & Anderssen, 2012 ). Assessment of Nutritional Status and Blood Biomarkers The Short-Form Mini Nutritional Assessment (MNA) was used to assess the nutritional status of each participant ( Rubenstein, Harker
Ronald J. Maughan, Louise M. Burke, Jiri Dvorak, D. Enette Larson-Meyer, Peter Peeling, Stuart M. Phillips, Eric S. Rawson, Neil P. Walsh, Ina Garthe, Hans Geyer, Romain Meeusen, Luc van Loon, Susan M. Shirreffs, Lawrence L. Spriet, Mark Stuart, Alan Vernec, Kevin Currell, Vidya M. Ali, Richard G.M. Budgett, Arne Ljungqvist, Margo Mountjoy, Yannis Pitsiladis, Torbjørn Soligard, Uğur Erdener and Lars Engebretsen
systems of nutrient status (deficiency/subclinical, deficiency/normal). When suboptimal nutritional status is diagnosed, the use of a nutrient supplement to reverse or prevent further deficiencies can contribute to the overall treatment plan. Nutritional assessment of an athlete involves systematic
Armand E.O. Bettonviel, Naomi Y.J. Brinkmans, Kris Russcher, Floris C. Wardenaar and Oliver C. Witard
The nutritional status of elite soccer players across match, postmatch, training and rest days has not been defined. Recent evidence suggests the pattern of dietary protein intake impacts the daytime turnover of muscle proteins and, as such, influences muscle recovery. We assessed the nutritional status and daytime pattern of protein intake in senior professional and elite youth soccer players and compared findings against published recommendations. Fourteen senior professional (SP) and 15 youth elite (YP) soccer players from the Dutch premier division completed nutritional assessments using a 24-hr web-based recall method. Recall days consisted of a match, postmatch, rest, and training day. Daily energy intake over the 4-day period was similar between SP (2988 ± 583 kcal/day) and YP (2938 ± 465 kcal/day; p = .800). Carbohydrate intake over the combined 4-day period was lower in SP (4.7 ± 0.7 g·kg-1 BM·day-1) vs. YP (6.0 ± 1.5 g·kg-1 BM·day-1, p = .006) and SP failed to meet recommended carbohydrate intakes on match and training days. Conversely, recommended protein intakes were met for SP (1.9 ± 0.3 g·kg-1 BM·day-1) and YP (1.7 ± 0.4 g·kg-1 BM·day-1), with no differences between groups (p = .286). Accordingly, both groups met or exceeded recommended daily protein intakes on individual match, postmatch, rest and training days. A similar “balanced” daytime pattern of protein intake was observed in SP and YP. To conclude, SP increased protein intake on match and training days to a greater extent than YP, however at the expense of carbohydrate intake. The daytime distribution of protein intake for YP and SP aligned with current recommendations of a balanced protein meal pattern.
International Olympic Committee Expert Group on Dietary Supplements in Athletes
. Supplement-induced performance changes should be interpreted in light of what is meaningful to the outcome of sporting competition. It must be remembered, though, that absence of evidence of efficacy is not the same as evidence of absence of efficacy. A comprehensive nutrition assessment is the first step in