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Jennifer C. Gibson, Lynneth Stuart-Hill, Steven Martin and Catherine Gaul

Context:

Adolescent female team-sport athletes are faced with the challenge of meeting nutrition requirements for growth and development, as well as sport performance. There is a paucity of evidence describing the dietary adequacy of this population in respect to these physiological demands. Therefore, the aim of this study was to comprehensively evaluate the nutrition status of junior elite female soccer athletes.

Method:

A total of 33 athletes (15.7 ± 0.7 yr) completed anthropometric assessment, 4-day food records analyzed for macro- and micronutrient intake, and hematological analysis. Energy expenditure was estimated using predictive equations.

Results:

Mean sum of 7 skinfolds was 103.1 ± 35.2 mm, and body-mass index was 22.7 ± 2.7. Mean energy intake was 2,079 ± 460 kcal/day, and estimated energy expenditure was 2,546 ± 190 kcal/day. Of the athletes, 51.5% consumed <5g/kg carbohydrate, 27.3% consumed <1.2g/kg protein, and 21.2% consumed <25% of energy intake from fat. A large proportion of athletes did not meet Dietary Reference Intakes for pantothenic acid (54.5%), vitamin D (100%), folate (69.7%), vitamin E (100%), and calcium (66.7%). Compared with recommendations for athletes, 89.3% and 50.0% of participants had depleted iron and 25-hydroxyvitamin D, respectively.

Conclusion:

A high proportion of players were not in energy balance, failed to meet carbohydrate and micronutrient recommendations, and presented with depleted iron and vitamin D status. Suboptimal nutrition status may affect soccer performance and physiological growth and development. More research is needed to understand the unique nutrition needs of this population and inform sport nutrition practice and research.

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Floris C. Wardenaar, Ingrid J.M. Ceelen, Jan-Willem Van Dijk, Roland W.J. Hangelbroek, Lore Van Roy, Britte Van der Pouw, Jeanne H.M. De Vries, Marco Mensink and Renger F. Witkamp

The use of nutritional supplements is highly prevalent among athletes. In this cross-sectional study, we assessed the prevalence of nutritional supplement use by a large group of Dutch competitive athletes in relation to dietary counseling. A total of 778 athletes (407 males and 371 females) completed a web-based questionnaire about the use of nutritional supplements. Log-binomial regression models were applied to estimate crude and adjusted prevalence ratios (PR) for the use of individual nutritional supplements in athletes receiving dietary counseling as compared with athletes not receiving dietary counseling. Of the athletes, 97.2% had used nutritional supplements at some time during their sports career, whereas 84.7% indicated having used supplements during the last 4 weeks. The top ranked supplements used over the last 4 weeks from dietary supplements, sport nutrition products and ergogenic supplements were multivitamin and mineral preparations (42.9%), isotonic sports drinks (44.1%) and caffeine (13.0%). After adjustment for elite status, age, and weekly exercise duration, dietary counseling was associated with a higher prevalence of the use of vitamin D, recovery drinks, energy bars, isotonic drinks with protein, dextrose, beta-alanine, and sodium bicarbonate. In contrast, dietary counseling was inversely associated with the use of combivitamins, calcium, vitamin E, vitamin B2, retinol, energy drinks and BCAA and other amino acids. In conclusion, almost all athletes had used nutritional supplements at some time during their athletic career. Receiving dietary counseling seemed to result in better-informed choices with respect to the use of nutritional supplements related to performance, recovery, and health.

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Emily M. Haymes

Muscle glycogen is the primary source of energy during high intensity exercise. Increasing the carbohydrate content of the diet allows more glycogen to be stored. Some adolescent female athletes (gymnasts, dancers) do not consume adequate amounts of vitamin B6, folacin, and E. Many women have low dietary intakes of calcium and iron. Low calcium intake and physical inactivity are factors associated with the development of osteoporosis. Low iron intake is associated with the development of iron deficiency and anemia. Low ferritin levels (an index of body iron stores) are commonly observed in female athletes.

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Heidi L. Petersen, C. Ted Peterson, Manju B. Reddy, Kathy B. Hanson, James H. Swain, Rick L. Sharp and D. Lee Alekel

This study determined the effect of training on body composition, dietary intake, and iron status of eumenorrheic female collegiate swimmers (n = 18) and divers (n = 6) preseason and after 16 wk of training. Athletes trained on dryland (resistance, strength, fexibility) 3 d/wk, 1.5 h/d and in-water 6 d/wk, nine, 2-h sessions per week (6400 to 10,000 kJ/d). Body-mass index (kg/m2; P = 0.05), waist and hip circumferences (P ≤ 0.0001), whole body fat mass (P = 0.0002), and percentage body fat (P ≤ 0.0001) decreased, whereas lean mass increased (P = 0.028). Using dual-energy X-ray absorptiometry, we found no change in regional lean mass, but fat decreased at the waist (P = 0.0002), hip (P = 0.0002), and thigh (P = 0.002). Energy intake (10,061 ± 3617 kJ/d) did not change, but dietary quality improved with training, as refected by increased intakes of fber (P = 0.036), iron (P = 0.015), vitamin C (P = 0.029), vitamin B-6 (P = 0.032), and fruit (P = 0.003). Iron status improved as refected by slight increases in hemoglobin (P = 0.046) and hematocrit (P = 0.014) and decreases in serum transferrin receptor (P ≤ 0.0001). Studies are needed to further evaluate body composition and iron status in relation to dietary intake in female swimmers.

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Satya S. Jonnalagadda, Paula J. Ziegler and Judy A. Nelson

The objectives of this study were to determine food preferences, body image perceptions, dieting behaviors, and nutrient intakes of elite male and female figure skaters. Male (n = 23) and female (n = 26) figure skaters completed a food preference checklist, a questionnaire examining their demographics, dieting behaviors and body image perceptions, and 3-d food records. Male skaters had a higher preference (score ≥ 6) for grains, fruit, meat, dairy, fats, and sweets. Female skaters had higher preference for grains and fruits. Of the female skaters, 30% considered themselves overweight and indicated a preference for a thinner body contour. Both male and female skaters expressed a preference for leaner body contours for members of the opposite gender. Total energy intake, total fat (females) and dietary fiber were below the dietary recommendations. Vitamin E, vitamin D, folate (females), pantothenic acid (females), calcium (females), magnesium, potassium, and phosphorus (females) were less than two-thirds of the dietary recommendations. Macronutrient intake of male skaters was associated with preferences for the grain group, although no association was observed among female skaters. Results suggest that these behaviors and attitudes need to be assessed and addressed among figure skaters, given their impact on dietary intakes and overall well-being.

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Susan M. Kleiner, Terry L. Bazzarre and Barbara E. Ainsworth

The nutritional status of 11 female and 13 male elite bodybuilders at the first drug-tested USA Championship was examined through food records kept by subjects. Diets were repetitive and monotonous, and average daily energy and protein contents were relatively similar for men and women. Percent calories from protein, fat, and carbohydrate were 39%, 12%, and 48% for females, and 40%, 11%, and 49% for males, respectively. Females consumed 0% vitamin D, 52% calcium, 76% zinc (as percents of RDA) and below the Estimated Safe and Adequate Dietary Allowance amounts for copper and chromium. Males consumed 46% of vitamin D RDA. Although dietary magnesium intakes were above the RDA, serum magnesium levels in females were below reference values, which should be investigated. Serum zinc levels were high in men and women. Eighty-one percent of females reported recurrent contest-related amenorrhea for 2 ± 1 months precontest. Dietary intakes of men were adequate but the restrictive intakes of women may place them at risk for calcium, copper, and chromium deficiencies.

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Jongkyu Kim, Namju Lee, Jangwon Lee, Sung-sook Jung, Sung-ki Kang and Jong-dae Yoon

This research investigated patterns of the use of dietary supplement and doping awareness among high-ranked judoists from 2 countries. Korean (70 men and 31 women) and Japanese (37 men and 34 women) national judo team members were divided into 2 groups (high and low competitive performance levels) according to their international and national rankings. Fifty-nine percent of Korean and 61% of Japanese judoists consumed dietary supplements. Eighty-eight percent of high- and 51% of low-competitive-performance-level Korean judoists consumed dietary supplements. Sixty-eight percent of high- and 57% of low-competitiveperformance- level Japanese judoists consumed dietary supplements. Oriental supplements (34%), vitamins (23%), and protein powder (12%) were the most commonly consumed dietary supplements in Korean judoists. Vitamins (45%), protein powder (33%), and minerals (15%) were the most commonly consumed dietary supplements in Japanese judoists. Thirty-eight percent of judoists from both countries had not received any proper education about antidoping, and 44% of judoists from both countries had not received knowledge of antidoping legislation. There was a significant difference in education about antidoping between high and low competitive-performance levels of Korean judoists (p < .001). Korean judoists received significantly less antidoping education than Japanese judoists (p < .001). The associations for antidoping education and knowledge of antidoping legislation with the use of dietary supplements were 3.46 (95% CI = 1.31–9.12) and 1.63 (95% CI = 0.71–3.76), respectively. Our findings showed that use of dietary supplements in judoists from both countries was increased after experiencing antidoping education.

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Anni Heikkinen, Antti Alaranta, Ilkka Helenius and Tommi Vasankari

The aim of this study was to evaluate the frequency of dietary supplement (DS) use among elite Finnish athletes in 2002 and 2009. In 2009, the authors also wanted to examine the reasons for athletes’ DS use, whether athletes feel they have experienced benefits from their supplement use, and whether athletes had had an opportunity to consult dietary specialists. Cross-sectional studies were conducted in 2002 and 2009 among Finnish Olympic athletes. Data were collected using semistructured questionnaires, mainly in national team camps. The study population in 2002 was 446 athletes, and in 2009 it was 372. The number of DS users was high in both study years (81% in 2002 and 73% in 2009). Vitamin D consumption was low in both 2002 and 2009 (0.7% and 2.0%, respectively). An increase was found in consumption of omega-3 fatty acids between study years (11% in 2002 and 19% in 2009; p = .002), and their regular use nearly doubled (8% and 15%, p = .002). For vitamin and mineral users, the main reason for DS use was to prevent nutritional deficiencies, and for nutritional supplement users the main reason was recovery from exercise. Only 27% of all athletes and 30% of DS users had an opportunity to consult dietary specialists in 2009. This survey shows that supplementation rates among elite Finnish athletes are high and there may be over- and underuse of some micronutrient supplements. There is a need for professional nutritional counseling among national elite athletes.

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Rameswar Pal, Som Nath Singh, Kaushik Halder, Omveer Singh Tomer, Awadh Bihari Mishra and Mantu Saha

Background:

This study was conducted to evaluate the effects of yogic practice on resting metabolism and redox status.

Methods:

The study was conducted on 64 physically trained male volunteers selected randomly at the Air Force Academy. The yoga group (n = 34) practiced yogasana, pranayama, and meditation for 3 months (February–May 2011) and the control group (n = 30) performed physical training. Antioxidant variables in blood samples along with physiological parameters were estimated before and after 3 months.

Results:

No significant difference was noted between baseline data of the control group and yoga group. Reduced glutathione, vitamin C, and vitamin E; the ratio of reduced to oxidized glutathione; and total antioxidant status were increased significantly following yogic practice. Activities of superoxide dismutase, glutathione S-transferase, and glutathione reductase were significantly increased, whereas activity of glutathione peroxidase was significantly decreased following yogic practice. Oxidized glutathione decreased significantly following yogic practice. A nonsignificant decrease of hydroperoxides, protein carbonyl, malondialdehyde, and blood sugar was noted in the yoga group. Carbon dioxide elimination and peripheral oxygen saturation increased significantly following yogic practice. No significant changes were observed in the control group following 3 months of physical training.

Conclusions:

Regular yogic practice can improve resting metabolism and redox status of the practitioner.

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Gary Slater, Benedict Tan and Kong Chuan Teh

The supplementation practices of elite athletes in Singapore were studied using an anonymous questionnaire. Information was sought on not only the type of supplements used but also dosage, rationale for use, and other factors that might influence supplement use including selected demographic parameters and sources of information relating to supplements. Data was collected from 160 athletes across a spectrum of 30 sports. Use of supplements was widespread, with 77% of respondents acknowledging use of at least 1 product. Respondents ingested a total of 59 different supplements, with each athlete using on average 3.6 ± 0.3 different products. Sports drinks, caffeine, vitamin C, multivitamin/mineral supplements, and essence of chicken were some of the most commonly ingested products, confirming that while vitamin/mineral supplements are popular, sports supplements and traditional/herbal preparations were also well accepted. Respondents preferred to source information pertaining to supplements from “significant others” and other readily accessible sources. A small number of respondents acknowledged the use of International Olympic Committee (IOC) banned or restricted substances, highlighting the need for athletes to consult sports medicine professionals with specialist knowledge of dietary supplements in advance of initiating any supplementation regime.