Research On Nutritional Status And Dietary Intervention Of Shanghai Elite Athletes And The Effect Of Lycium Barbarum Polysaccharides On Relieving Physical Fatigue Of Mice

Objectives: 1.(1) In order to learn the energy, nutrients intake and body metabolism of Shanghai elite athletes, we did dietary surveys, physical and biochemical detection, then assessed their nutritional status.(2) For questions found by dietary surveys, we hoped to help athletes improve their nutritional status by means of nutrition counseling, nutrition lectures, issuance of nutrition knowledge brochure and preparing recipes.(3) In order to find the main nutritional problems existing in Shanghai elite athletes, and explore the feasibility of dietary balance index applied to evaluate the nutritional status of athletes, we evaluated dietary quality of Shanghai elite athletes with an adjusted dietary balance index.2. We research the effect of Lycium Barbarum Polysaccharides(LBP) on relieving physical fatigue of mice, providing basis for LBP health functions and helping athletes improve exercise ability.Methods: 1. Research on nutritional status and dietary intervention of Shanghai elite athletes(1) We conducted the dietary surveys by weighting food for three consecutive days, and determined vitamin B1(VB1), vitamin B2(VB2), vitamin C(VC) by vitamin urinary stress test, we also collected blood samples of athletes, determined serum minerals by using atomic absorption spectrometry when athletes were normal training state.(2) Depending on the sport, we personalized nutritional guidance and intervention. We investigated the work of chef, communicated the questions existing with cooks and other staff timely, did the nutrition knowledge education for cooks and relevant staff, guided the chef to cater, reported dietary survey results for different coaches, athletes and lead, did nutrition knowledge lectures, issued nutritional knowledge brochures.(3) In the latest revision of the Chinese diet balance index, we adjusted the dietary balance index based on the nutrients and food appropriate intake of Chinese athletes. According to the food intake, we evaluated the dietary quality of Shanghai elite athletes.2. The effect of LBP on relieving physical fatigue of miceMice were divided into four groups, then each group was divided into four subgroups, one control group and three LBP treated groups(8.3, 16.7, 33.4mg/(kg·bw))for 30 days. On the last day, we carried out the swimming test, and determined glycogen content of liver, urea nitrogen in serum and lactic acid in blood, and assessed the effect of LBP on body weight and relieving physical fatigue of mice.Results:1. Research on nutritional status and dietary intervention of Shanghai elite athletes(1) Most of the athletes did not intake enough energy, but the energy ratio of protein was higher, and carbohydrate was lower. All of the athletes took enough VC, but did not take enough vitamin A(VA), vitamin B1(VB1), vitamin B6(VB6) and folic acid, and some of them did not take enough vitamin B2(VB2), Niacin(VPP), Calcium(Ca),(Potassium)K, Magnesium(Mg) and Zinc(Zn), but took much more vitamin E(VE), Sodium(Na) and Iodine(I)than the adequate intake recommended for athletes. The energy distribution of each meal was not reasonable, and the energy of breakfast and lunch was lower, but the dinner and snacks were higher. Athletes did not take enough cereals, milk, legume, vegetables and fruit.(2) From the vitamin urinary stress test, we knew that the incidences of VB1 and VB2 insufficiency were 18.5%, 48.1% respectively of female athletes, the incidences of VB1 and VB2 deficiency were 9.3%, 25.9% of female athletes. The incidences of VB1 and VB2 insufficiency were 20%, 54.3% respectively of male athletes, the incidences of VB1 and VB2 deficiency were 5.7%, 31.4% of male athletes. The serum copper levels between male and female athletes were different(P< 0.05). Serum iron levels among different sports were significantly different(P< 0.05). There were significant correlations of energy, carbohydrate, vitamin C with serum copper, there were significant correlations of serum calcium, dietary calcium, carbohydrate with serum iron.(3) Evaluation on the dietary quality of Shanghai elite athletes with an adjusted dietary balance index, the medium of LBS was 27, and there were 51.64 percent of athletes having middle and high level of insufficient intake. The medium of HBS was 2, and all athletes did not have excessive intake. The medium of DQD was 29, and there were 40.66 percent of athletes having middle and high level of overall imbalance. The HBS between male and female athletes was different(P< 0.05). The LBS and DQD among different sports were different(P< 0.05).2.The swimming time of mice in middle and high level LBP treated groups were significantly prolonged compared with that in the control group(P< 0.05); glycogen content of liver of mice in LBP treated groups were significantly increased compared with that in the control group(P< 0.05), the level of urea nitrogen in serum and lactic acid in blood of mice in LBP treated groups were significantly decreased compared with that in the control group(P< 0.05). LBP does not have any effect on body weight of mice.Conclusion: Due to lack of nutrition knowledge and awareness of the importance of a balance diet, the problems of overestimating the importance of protein, ignoring the nutrition value of stable foods, vegetables improper selection of food, resulting in high-protein, low-carbohydrate and vitamin B deficiency existed. Adjusted dietary balance index evaluation system can objectively reflect the dietary and nutritional status of athlete groups and individual, and find that diet quality of Shanghai elite athletes are not ideal. We should pay attention to the situation. LBP does not have any effect on body weight, but can increase the swimming time and the amount of glycogen reserves, reducing blood urea nitrogen and serum lactate levels, so LBP can relieve physical fatigue.