Nutrition for winter sports

Cross-Sectional Study of the Anthropometric Profile and Nutrient Status of Elite Female Ice Hockey Players: Differences by Play Position

Both the characteristics of ice hockey and the environmental conditions in which it is played affect the maintenance of the player's nutritional status and, therefore, their state of health and performance. The primary aim of this work was to examine the anthropometric profile, estimated energy expenditure, and macronutrient and micronutrient dietary intake of elite female ice hockey players by play position. As a secondary aim, their dietary intakes were compared with the recommendations. Hypotheses suggest variations in body composition based on ice hockey players' positions, with the expectation that these athletes may not align with energy and nutrient recommendations. Fifteen elite female ice hockey players were anthropometrically measured, basal metabolic rate and total energy expenditure were estimated, a 3-day, 24 h recall questionnaire was registered, and the results were compared with the recommended dietary intake for the Spanish population. Each player's position on the field requires an individualized physical and nutritional approach. There are no significant imbalances (p > 0.05) between energy and nutrient intake in relation to the Recommended Daily Intake (RDI); however, increasing the consumption of vegetables and seafood while reducing meat and fat intake would assist these athletes in maintaining a healthier energy balance, optimizing body composition, and aligning with nutritional parameters that are better suited to enhance physical performance.

Nutrition Status of Female Winter Sports Athletes

Eating disorders, especially restrictive eating, are common among female athletes. There are two main types of winter sports: those that are practiced outdoors on snow (-25 to +5 °C and 2500 m), such as alpine skiing and snowboarding, and those that are practiced indoors on ice (5-10 °C at low altitude), such as figure skating and ice hockey. The aim of this research was to identify the nutritional status and potential risk of female athletes practicing winter sports, considering the altitude of training. The sample was composed of 58 women (aged 19.81 years (SD: 12.61)) who were competitors in some winter sports. Anthropometrics and nutritional variables were taken. Statistically significant differences were found between HA and LA groups for all the characteristics except thigh skinfold, and neither group had an energy intake (EI) that matched their total energy expenditure (TEE). Both groups met at least two-thirds of the RDI for all minerals and vitamins except iodine, fluorine, vitamin D, vitamin E, and retinol. This study suggests that female winter sports athletes have insufficient energy, vitamin, and mineral intake, which can be worsened with altitude.

Seasonal Oxy-Inflammation and Hydration Status in Non-Elite Freeskiing Racer: A Pilot Study by Non-Invasive Analytic Method

Freeskiing is performed in an extreme environment, with significant physical effort that can induce reactive oxygen species (ROS) generation and dehydration. This study aimed to investigate the evolution of the oxy-inflammation and hydration status during a freeskiing training season with non-invasive methods. Eight trained freeskiers were investigated during a season training: T0 (beginning), T1-T3 (training sessions), and T4 (after the end). Urine and saliva were collected at T0, before (A) and after (B) T1-T3, and at T4. ROS, total antioxidant capacity (TAC), interleukin-6 (IL-6), nitric oxide (NO) derivatives, neopterin, and electrolyte balance changes were investigated. We found significant increases in ROS generation (T1A-B +71%; T2A-B +65%; T3A-B +49%; p < 0.05-0.01) and IL-6 (T2A-B +112%; T3A-B +133%; p < 0.01). We did not observe significant variation of TAC and NOx after training sessions. Furthermore, ROS and IL-6 showed statistically significant differences between T0 and T4 (ROS +48%, IL-6 +86%; p < 0.05). Freeskiing induced an increase in ROS production, which can be contained by antioxidant defense activation, and in IL-6, as a consequence of physical activity and skeletal muscular contraction. We did not find deep changes in electrolytes balance, likely because all freeskiers were well-trained and very experienced.

Figure skating: Increasing numbers of revolutions in jumps at the European and World Championships

Figure skating is associated with a high prevalence of sport-specific injuries and overuse symptoms. Impacts are of greater magnitude in jumps with more revolutions that are thus connected to a greater risk of injury. While figure skating programs seem to have recently increased in difficulty, performance trends have not yet been reported in the literature. We hypothesized increasing performance and decreasing age trends of the best athletes who competed at international level in recent years. Furthermore, we aimed to identify and analyse objective performance parameters and to assess a potential link between age and the risk of injury. The development of the number of double, triple and quadruple jumps in the singles figure skating events at the World and European Championships since the introduction of the new ISU Judging System in the 2004/2005 season was analysed using regression statistics and Student's T-Tests. In all groups, the numbers of jumps with fewer rotations significantly decreased in the favour of jumps with more rotations. Women only started to perform jumps with four rotations in 2019. In the men, the number of quadruple jumps increased from an average of less than one to more than three in recent years (European and World Championships, both p < 0.001). In the European, but not in the World Championships, the average age increased in the men and decreased in the women (European Championships, men and women p = 0.006). Our study was the first to assess performance trends in elite figure skating. The incidence of injuries and overuse syndromes in figure skating needs to be monitored cautiously, as increases can be expected following recent gains in performance and jump complexity.

A questionnaire study on the knowledge, attitudes, and practices of fluid replacement and urination among Chinese elite athletes

OBJECTIVE

To evaluate the knowledge, attitudes and practices (KAP) of Chinese elite athletes about fluid replacement and urination.

METHODS

A cross-section study was carried out among Chinese national and national youth teams from March to April 2020, using a pretested questionnaire. The 42-questions questionnaire was designed to assess the KAP regarding fluid replacement and urination. The questionnaire included knowledge of fluid replacement (KFR), attitudes of fluid replacement (AFR), knowledge of urination (KU), and attitudes of urination (AU), which were awarded 20 scoring points. Descriptive statistics, independent samples t-tests, one-way ANOVA, Pearson's correlation analysis, Multiple linear stepwise regression and Chi-square test were performed.

RESULTS

A total of 779 valid questionnaires were collected and the effective rate is 98.4%. We finally conducted an assessment of 646 questionnaires of elite athletes. The mean score for KFR, AFR, KU, and AU was 2.8±1.3, 2.3±0.6, 3.0±1.5, and 2.1±0.8, respectively, with higher scores indicating positive hydration knowledge and attitudes. KFR and AFR scores of winter sports athletes were higher than those of summer sports athletes(P<0.05). Athletes who had lower athletic grades and training years had a worse KFR(P<0.05). Only 31.0% athletes knew that rehydration should be carried out before, during, and after training, which was scarcer among women, lower-athletic grades athletes, or athletes with lower training years (P<0.05). Male athletes had a worse KU but a better AU than female athletes(P<0.05). And athletes who were international-class athletic grades had the highest KU scores(P<0.05). The athletic grades and sport events were the main factors influencing the total scores of knowledge and attitudes (P<0.05, 95% CI -0.789--0.168,95% CI 0.025-1.040). Most of athletes tend to get hydration knowledge from internet. In practices, thirst is the main reason for rehydration (77.9%). The percentages of athletes with normal urine color (42.0%), frequency (75.0%,) and volume (20.0%) were low.

CONCLUSIONS

These findings indicate that Chinese elite athletes did not have sufficient KAP on fluid replacement and urination, more marked in the individuals who were summer sport events, the lower athletic grades and in lower training years. It is recommended that education should be provided in the early stages of professional training for athletes.

COVID-19: Sports activity and health-related quality of life of Swiss children and adolescents before and during the initial stay at home period

The aim of this study was to investigate sports activity and health-related quality of life (HRQoL) of Swiss children and adolescents (7–16 years) during the national COVID-19 stay at home (SaH) period. In total, 237 parent-child pairs gave information about HRQoL and sports activity (duration and type) before and during SaH. Results show that sports activity decreased during SaH and was also positively related to HRQoL. These findings indicate that sports activity of children and adolescents should be promoted during SaH, for which innovative home-based interventions may be useful.

How Ice Rink Locations Affect Performance Time in Short-Track Speed Skating

Purpose

To accurately provide evaluations on how match performance for elite skaters in short track speed skating developed, and whether geographical factors of ice rink locations should be considered apart from technical abilities. We created a dataset containing competition records from the 2013-14 to 2020-21 seasons (500 m event) on the official website.

Methods

One-way ANOVA was applied to statistically analyze whether the best performance times exhibited significant differences in varied hosting cities. Performance-time matrix and multivariate regression model were further established to quantitatively explain how geographical factors (longitude, latitude, altitude, and barometric pressure) affected performance.

Results

Our findings firstly confirmed that the fastest 500 m finishing times varied due to the hosting cities (P = 0.008) and showed that venue locations could boost or impair performance time with the maximum range of 3.6 s. Meanwhile, latitude (slightly over 46° when performance is maximized) was the most influential factor to account for the performance-time difference in different ice rink locations according to the multivariate regression model, though altitude (1,225 meters when performance is maximized) was also important.

Conclusions

In this perspective, elite skaters should check the geographical factors of the venues before they participated in the upcoming competitions, assess the real strength of their rivals, and adopt flexible tactics during training sessions.

The Road to the Beijing Winter Olympics and Beyond: Opinions and Perspectives on Physiology and Innovation in Winter Sport

Beijing will host the 2022 Winter Olympics, and China strengthens research on various aspects to allow their athletes to compete successfully in winter sport. Simultaneously, Government-directed initiatives aim to increase public participation in recreational winter sport. These parallel developments allow research to advance knowledge and understanding of the physiological determinants of performance and health related to winter sport. Winter sport athletes often conduct a substantial amount of training with high volumes of low-to-moderate exercise intensity and lower volumes of high-intensity work. Moreover, much of the training occur at low ambient temperatures and winter sport athletes have high risk of developing asthma or asthma-related conditions, such as exercise-induced bronchoconstriction. The high training volumes require optimal nutrition with increased energy and dietary protein requirement to stimulate muscle protein synthesis response in the post-exercise period. Whether higher protein intake is required in the cold should be investigated. Cross-country skiing is performed mostly in Northern hemisphere with a strong cultural heritage and sporting tradition. It is expected that innovative initiatives on recruitment and training during the next few years will target to enhance performance of Chinese athletes in classical endurance-based winter sport. The innovation potential coupled with resourcing and population may be substantial with the potential for China to become a significant winter sport nation. This paper discusses the physiological aspects of endurance training and performance in winter sport highlighting areas where innovation may advance in athletic performance in cold environments. In addition, to ensure sustainable development of snow sport, a quality ski patrol and rescue system is recommended for the safety of increasing mass participation.

Energy availability during training camp is associated with signs of overreaching and changes in performance in young female cross-country skiers

Study aim: The aim of this study was to evaluate if young female skiers meet their energy and macronutrient requirements, and how energy availability (EA) and macronutrient intake affects their performance during an intensive training camp.

Material and methods: 19 female cross-country skiers (age 16.7 ± 0.7) filled in 48-hour food and training logs during a 5-day training camp. Fasting concentrations of hemoglobin, leptin, triiodothyronine (T3), insulin, insulin-like growth factor 1 (IGF-1), and glucose were measured before (PRE) and after (POST) the camp. Blood lactate (LA), heart rate (HR) and rating of perceived exertion (RPE) from a submaximal treadmill running test, jump height from counter movement jump (CMJ), and power from a reactive jump test (RJ) were also measured PRE and POST.

Results: Mean EA was 40.3 ± 17.3 kcal · kgFFM–1 · d–1. 58% of the participants had suboptimal EA, 37% had low EA, and 53% had suboptimal carbohydrate intake. HR, HR/RPE ratio, LA/RPE ratio, CMJ, hemoglobin, leptin, T3, and insulin decreased from PRE to POST. RPE and glucose increased from PRE to POST. EA during the camp correlated with changes in LA (r = 0.54, p = 0.018), LA/RPE (r = 0.65, p = 0.003), and RJ (r = 0.47, p = 0.043).

Conclusions: Many athletes had difficulties in meeting their energy and carbohydrate requirements during a training camp. Furthermore, sufficient EA may help to avoid overreaching and to maintain performance during an intensive training period.

Hydration Status in Adolescent Alpine Skiers During a Training Camp

Maintaining euhydration is important for optimal health, performance and recovery, but can be challenging for alpine skiers when training in a relatively cold but dry environment. This study aimed to evaluate hydration status, fluid loss and fluid intake in adolescent alpine skiers during a training camp. Twelve athletes aged 14.3 ± 0.9 years volunteered to participate in the study. Athletes resided at an altitude of 1600 m and trained between 1614 and 2164 m. During eight consecutive days, urine specific gravity was measured before each morning training session using a refractometer. Changes in body weight representing fluid loss and ad libitum fluid intake during each morning training session were assessed using a precision scale. Mean pre-training urine specific gravity remained stable throughout the training camp. Individual values ranged between 1.010 and 1.028 g/cm³with 50 to 83% of athletes in a hypohydrated state (urine specific gravity ≥ 1.020 g/cm³). Mean training induced fluid loss remained stable throughout the training camp (range -420 to -587 g) with individual losses up to 1197 g (-3.5%). Fluid intake was significantly lower than fluid loss during each training session. To conclude, urine specific gravity values before training indicated insufficient daily fluid intake in more than half of the athletes. Furthermore, fluid intake during training in adolescent alpine skiers was suboptimal even when drinks were provided ad libitum. Coaches and athletes should be encouraged to carefully monitor hydration status and to ensure that alpine skiers drink sufficiently during and in between training sessions.

Key Nutritional Considerations for Youth Winter Sports Athletes to Optimize Growth, Maturation and Sporting Development

Despite a wealth of sport nutrition guidelines for adult athletes, there are currently no nutrition guidelines for youth winter sports athletes. Whilst it may be pragmatic to apply nutrition guidelines for adult athletes to youth winter sports athletes, it is inappropriate. Due to a paucity of research on youth athletes, it is impossible to provide evidence-based guidelines for this population, so careful extrapolation from the theoretical and practical considerations that apply to other athletic groups is necessary. Youth winter sport athletes undergo rapid biological growth and maturation which influences their nutritional requirements. A varied and balanced diet that ensures sufficient energy availability for optimal growth and maturation as well as sporting performance is the cornerstone of youth athlete nutrition and should also allow for youth athletes to meet their micronutrient requirements. In some cases, micronutrient status (e.g., vitamin D and iron) should be monitored and optimized if appropriate by a medical professional. Dietary supplement use is prevalent amongst youth athletes, however is often unnecessary. Education of youth athletes, their parents and coaches on best nutritional practices as well as the risks associated with dietary supplements is vital for their long-term athletic development. Further research in youth winter sports athletes across different stages of growth and maturation competing in a variety of sports is urgently required in order to inform nutritional guidelines for this population.

Nutrition and Altitude: Strategies to Enhance Adaptation, Improve Performance and Maintain Health: A Narrative Review

Training at low to moderate altitudes (~ 1600-2400 m) is a common approach used by endurance athletes to provide a distinctive environmental stressor to augment training stimulus in the anticipation of increasing subsequent altitude- and sea-level-based performance. Despite some scientific progress being made on the impact of various nutrition-related changes in physiology and associated interventions at mountaineering altitudes (> 3000 m), the impact of nutrition and/or supplements on further optimization of these hypoxic adaptations at low-moderate altitudes is only an emerging topic. Within this narrative review we have highlighted six major themes involving nutrition: altered energy availability, iron, carbohydrate, hydration, antioxidant requirements and various performance supplements. Of these issues, emerging data suggest that particular attention be given to the potential risk for poor energy availability and increased iron requirements at the altitudes typical of elite athlete training (~ 1600-2400 m) to interfere with optimal adaptations. Furthermore, the safest way to address the possible increase in oxidative stress associated with altitude exposure is via the consumption of antioxidant-rich foods rather than high-dose antioxidant supplements. Meanwhile, many other important questions regarding nutrition and altitude training remain to be answered. At the elite level of sport where the differences between winning and losing are incredibly small, the strategic use of nutritional interventions to enhance the adaptations to altitude training provides an important consideration in the search for optimal performance.

Alpine junior world ski championship: nutritional habits and performance in elite skiers

BACKGROUND

Young athletes need to consume an appropriate diet in order to maintain health and optimize growth and athletic performance. We evaluated nutritional habits of junior elite skiers.

METHODS

Alpine junior elite skiers (N.=68; 42 males and 26 females; age range 16-20 years) coming from 20 countries were recruited during the Alpine Junior World Ski Championship, Roccaraso, Italy. Nutritional habits were assessed using a 3-day food record and the NHANES Food Frequency Questionnaire. Data were compared with nutritional recommendations and Recommended Dietary Allowances (RDAs) for athletes.

RESULTS

During the training period, the energy intake in both males and females was significantly lower with respect to estimated energy needs. Carbohydrate intake expressed in terms of grams per kilogram of body weight did not meet the RDAs in both groups (4.19 and 5.15 g/kg in males and females, respectively). Protein and fat consumption exceeded the RDAs with a protein intake of 2.34 g/kg in males and 2.10 g/kg in females, and a fat intake >35% of total daily calories. During competition days, both males and females increased carbohydrate intake to 6.23 and 8.11 g/kg respectively, reaching the RDAs. Protein intake increased to 2.56 and 3.14 g/kg in males and females, respectively, and fat intake slightly decreased, still exceeding the RDAs.

CONCLUSIONS

Junior elite skiers reported a low intake of carbohydrates and a high intake of protein and fat. Nutritional counselling should be given to athletes to maintain their health and improve their physical performance.

American College of Sports Medicine Joint Position Statement. Nutrition and Athletic Performance

It is the position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine that the performance of, and recovery from, sporting activities are enhanced by well-chosen nutrition strategies. These organizations provide guidelines for the appropriate type, amount, and timing of intake of food, fluids, and supplements to promote optimal health and performance across different scenarios of training and competitive sport. This position paper was prepared for members of the Academy of Nutrition and Dietetics, Dietitians of Canada (DC), and American College of Sports Medicine (ACSM), other professional associations, government agencies, industry, and the public. It outlines the Academy's, DC's and ACSM's stance on nutrition factors that have been determined to influence athletic performance and emerging trends in the field of sports nutrition. Athletes should be referred to a registered dietitian/nutritionist for a personalized nutrition plan. In the United States and in Canada, the Certified Specialist in Sports Dietetics (CSSD) is a registered dietitian/nutritionist and a credentialed sports nutrition expert.

Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance

It is the position of the Academy of Nutrition and Dietetics (Academy), Dietitians of Canada (DC), and the American College of Sports Medicine (ACSM) that the performance of, and recovery from, sporting activities are enhanced by well-chosen nutrition strategies. These organizations provide guidelines for the appropriate type, amount, and timing of intake of food, fluids, and supplements to promote optimal health and performance across different scenarios of training and competitive sport. This position paper was prepared for members of the Academy, DC, and ACSM, other professional associations, government agencies, industry, and the public. It outlines the Academy's, DC's, and ACSM's stance on nutrition factors that have been determined to influence athletic performance and emerging trends in the field of sports nutrition. Athletes should be referred to a registered dietitian nutritionist for a personalized nutrition plan. In the United States and in Canada, the Certified Specialist in Sports Dietetics is a registered dietitian nutritionist and a credentialed sports nutrition expert.

Energy expenditure of extreme competitive mountaineering skiing

PURPOSE

Multi-hour ski mountaineering energy balance may be negative and intake below recommendations.

METHODS

Athletes on the 'Patrouille des Glaciers' racecourses (17 on course Z, 27 km, +2,113 m; 11 on course A, 26 km, +1,881 m) volunteered. Pre-race measurements included body mass, stature, VO2max, and heart rate (HR) vs VO2 at simulated altitude; race measurements HR, altitude, incline, location, and food and drink intake (A). Energy expenditure (EE) was calculated from altitude corrected HR derived VO2.

RESULTS

Race time was 5 h 7 min ± 44 min (mean ± SD, Z) and 5 h 51 min ± 53 min (A). Subjects spent 19.2 ± 3.2 MJ (Z), respectively, 22.6 ± 2.9 MJ (A) during the race. Energy deficit was -15.5 ± 3.9 MJ (A); intake covered 20 ± 7 % (A). Overall energy cost of locomotion (EC) was 9.9 ± 1.3 J m(-1) kg(-1) (Z), 8.0 ± 1.0 J m(-1) kg(-1) (A). Uphill EC was 11.7 ± 1 J m(-1) kg(-1) (Z, 13 % slope) and 15.7 ± 2.3 J m(-1) kg(-1) (A, 19 % slope). Race A subjects lost -1.5 ± 1.1 kg, indicating near euhydration. Age, body mass, gear mass, VO2max and EC were significantly correlated with performance; energy deficit was not.

CONCLUSIONS

Energy expenditure and energy deficit of a multi-hour ski mountaineering race are very high and energy intake is below recommendations.