Journal of the International Society of Sports Nutrition最新文献

Objective: The aim of this study was to identify the key regulatory mechanisms of cartilage injury and osteoporosis through bioinformatics methods, and to provide a new theoretical basis and molecular targets for the diagnosis and treatment of the disease.

Methods: Microarray data for cartilage injury (GSE129147) and osteoporosis (GSE230665) were first downloaded from the GEO database. Differential expression analysis was applied to identify genes that were significantly up-or down-regulated in the cartilage injury and osteoporosis samples. These genes were subjected to GO enrichment analysis and KEGG pathway analysis. In addition, we employed SVA and RRA methods to merge the two sets of data, eliminating batch effects and enhancing the statistical power of the analysis. Through WGCNA, we identified gene modules that were closely associated with disease phenotypes and then screened for key genes that intersected with differentially expressed genes. The diagnostic value of these genes as potential biomarkers was evaluated by ROC analysis. Moreover, we performed an immune infiltration analysis to explore the correlation between these core genes and immune cell infiltration.

Results: We performed GO enrichment analysis and KEGG pathway analysis of genes significantly up-or down-regulated in cartilage injury and osteoporosis samples. Important biological processes, cellular components and molecular functions, and key metabolic or signaling pathways associated with osteoporosis and cartilage injury were identified. Through WGCNA, we identified gene modules that were closely associated with the disease phenotype, from which we then screened for key genes that intersected with differentially expressed genes. Ultimately, we focused on two identified core genes, COL1A1 and TNFRSF12A, and assessed the diagnostic value of these genes as potential biomarkers by ROC analysis. Meanwhile, GSVA provided an in-depth view of the role of these genes in disease-specific biological pathways. Immune infiltration analysis further revealed the possible key role of COL1A1 and TNFRSF12A in regulating immune cell infiltration in osteoporosis and cartilage injury.

Conclusion: COL1A1 and TNFRSF12A as key regulatory molecules in osteoporosis and cartilage injury.

Background: Caffeine, identified as a central nervous system stimulant in foods, beverages (coffee, tea, chocolate), and medications, has been focused on its ergogenic properties, enhancing physical performance. The aim of this study was to investigate the association between the caffeine intake (from coffee) and fat-free mass index (FFMI).

Materials and methods: We carried out a cohort study that included 3,466 women and 3,145 men aged ≥20 years who were intaking caffeine. Caffeine intake from coffee were obtained from two 24-hour dietary recall interviews. The FFMI was calculated as FFM (kg) divided by height in m². The caffeine intake was classified into quartiles and combined into 4 groups. Multiple linear regression model analysis and multiple logistic regression model analysis were used to assess associations between the caffeine and FFMI adjusted for potential confounders.

Results: Among the 2,427 participants, males accounted for 52.4%, and females 47.6%. In multiple linear regression model, Model 1 (unadjusted Model (p = 0.041)) and Model 2 (adjusted for age, race, and BMI (p = 0.006)) in women showed a significant relationship between caffeine intake and FFMI. In multivariable models, caffeine intake and FFMI were significantly different (p < 0.05). In sex subgroups, among females, each quartile of caffeine intake was positively correlated with FFMI levels in the average FFMI group in Model 3 (p < 0.001). In age subgroups, each quartile of caffeine intake was positively correlated with FFMI levels in the average FFMI group in Model 3 for individuals aged 20-40 (p = 0.039) and those aged above 40 (p = 0.016). In drinking status subgroups, if they drunk alcohol, each quartile was positively correlated with FFMI levels in the average FFMI group in Model 3 (p < 0.001).

Conclusion: Caffeine intake was mainly positively associated with FFMI, especially in women with above levels of FFMI. Longitudinal studies and randomized controlled trials are needed to establish causality and provide evidence-based recommendations regarding caffeine intake to optimize muscle health.

Background: Relative Energy Deficiency in Sports (REDs) is defined as a multifactorial syndrome of impaired physiological and/or psychological functioning was previously named as the Female Athlete Triad. REDs was proposed to be an expansion of the Female Athlete Triad model (Triad), corresponding to a combination of Low Energy Availability (LEA), alteration of the menstrual cycle and bone health. could be made possible by a screening tool to determine the risk of LEA. The Low Energy Availability in Female-Questionnaire (LEAF-Q) is a screening tool originally developed to identify individuals at risk of Triad based on self-reported symptoms in three primary categories: injuries, gastrointestinal function, and reproductive function - to identify individuals at risk of Triad. To date, LEAF-Q is recommended in the International Olympic Committee REDs Clinical Assessment Tool-Version 2 as a screening tool for studying various health and performance outcomes of REDs. This study aims to validate the Italian version (LEAFQ-ITA) among physically active women while adapting it to their culture in order to enhance the diagnosis and facilitate access to treatment of REDs.

Methods: The validation process was carried out in multiple stages: (i) translation and cultural adaptation of the content from the original questionnaire (LEAF-Q) into the Italian culture; (ii) expert validation of the content using the Delphi technique; (iii) reliability test-retest in a sample of Italian physical active women; and (iv) internal consistency checking using exploratory and confirmatory factorial analysis. A consensus rate of more than 90% for every item was considered sufficient agreement. The test-retest reliability was evaluated using the intraclass correlation coefficient estimates and their 95% confidence intervals based on a mean-rating, absolute agreement, 2-way mixed-effects model. Exploratory and confirmatory factorial analyses were performed with the Factor software. The analysis was implemented using a matrix dispersion through Pearson correlations and the Robust Diagonally Weighted Least Squares (RDWLS) extraction method. The Parallel Analysis technique suggested the number of factors to be retained. McDonald's Omega and Cronbach's alpha were performed to test internal consistency.

Results: After two rounds, the LEAFQ-ITA maintained the same amount of items and gained the consensus of content validation specialists. From the sample of 215 questionnaires answered, a sub-sample of 105 participants answered the LEAFQ-ITA twice (mean age: 26.1 ± 4.7 years old; mean body mass index: 21.3 ± 2.6 kg/m²; physical activity of 3.9 ± 1.3 days/week on average). Among them, 56 women (37.6%) obtained a were classified at risk of LEA by the final score of LEAFQ-ITA ≥8. The single measurement intraclass correlation coefficient resulted in 0.832 (F = 10.849, df = 105, p < 0.00

Objective: The aim of this study was to investigate the effect of a 16/8 time-restricted eating (TRE) program over 6 weeks on body composition and lipolytic hormone levels in female DanceSport dancers. Importantly, participants were not subject to any calorie restrictions during the study period.

Methods: A total of 20 female DanceSport dancers were recruited to participate in the randomized controlled trial. The participants were randomly assigned to either a time-restricted eating group (TRE, n = 10) or a control group (n = 10). The TRE group adhered to a 16/8 time-restricted eating protocol for a period of six weeks, consuming food within an eight-hour window (11:00-19:00) and fasting for 16 hours. The control group was instructed to maintain their usual dietary habits without any intervention. Body composition parameters, including body fat percentage (BF%), fat mass (FM), and fat-free mass (FFM), were measured before and after the intervention. Additionally, serum levels of epinephrine (E), norepinephrine (NE), adiponectin (ADPN), leptin (LEP), growth hormone (GH), insulin-like growth factor 1 (IGF-1), and blood lipid profiles (including total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides (TG)) were assessed.

Results: After 6 weeks, the TRE group showed significant reductions in FM and BF% compared to baseline (p < 0.01). No significant changes were observed in body weight or FFM (p > 0.05). Regarding blood lipid profiles, HDL-C levels significantly increased in the TRE group (p < 0.05) following the 6-week intervention. In contrast, no significant changes were observed in TC, TG and LDL-C (p>0.05). Hormonal analysis revealed significant changes in the TRE group. Serum levels of epinephrine (E) and norepinephrine (NE) increased significantly following the intervention (p < 0.05), with E showing a particularly marked increase (p < 0.01). Additionally, serum adiponectin (ADPN) levels were significantly elevated (p < 0.05), while GH, IGF-1 and LEP levels did not show significant changes (p > 0.05). Group-by-time interactions were observed for FM (p < 0.05), BF% (p < 0.05), and E (p < 0.05). Comparisons of baseline and post-intervention dietary data indicated no significant changes in total calorie or macronutrient intake within either the TRE or control groups (p > 0.05).

Conclusion: Time-restricted eating without caloric restriction may offer a promising approach to regulating body composition and promoting lipid metabolism, especially for female DanceSport dancers where maintaining a lean body mass is critical. However, the long - term effects of this approach still warrant continued observation.

Introduction: Established guidelines recommend carbohydrate-rich diets to optimize performance in endurance sports. However, alternative dietary strategies, such as the low-arbohydrate and high-fat (LCHF) diet, have gained increasing attention due to their potential to influence metabolic flexibility and endurance performance outcomes. In this study, we aim to investigate the combined effects of a LCHF diet, along with low glycemic index (LOW-GI) and high glycemic index (HIGH-GI) diets, in conjunction with regular endurance exercise, on the metabolomic profiles of recreational runners. The classification into LOW-GI and HIGH-GI groups is based on the premise that metabolic regulation, particularly insulin response and glucose metabolism, differs significantly between the consumption of high-glycemic and low-glycemic foods.

Methods: The participants (n = 49, 28 ± 4 years, BMI: 24.2 ± 2.8 kg/m2, VO2 peak: 56 ± 8 ml/min/kg) were randomly allocated to a LOW-GI (n = 16), a HIGH-GI (n = 16) or a LCHF (n = 17) diet for 10 weeks and the same endurance training intervention. Fasting plasma samples were collected both pre- and post-intervention and were prepared for non-targeted metabolomic analysis using liquid chromatography coupled to high-resolution mass spectrometry.

Results: The LCHF diet had a considerable impact on plasma lipids, whereas the respective effects in the LOW-GI and HIGH-GI groups were less pronounced. Specifically, 179 up- or down-regulated metabolites were identified in the LCHF group, 111 in the LOW-GI group, and 139 in the HIGH-GI group. Phospholipids and sphingolipids were found to be the most prominent metabolites in the samples. Furthermore, the regulation of glycerolipids, carnitine, amino acids, and carbon acids exhibited differential patterns across the groups.

Discussion: There is evidence to suggest that the LCHF diet enhances fat metabolism, as indicated by increased levels of carnitine and ketone bodies, as well as a downregulation of amino acids. Conversely, the presence of specific carbon acids might diminish carbohydrate metabolism and impair endurance performance. In contrast, the LOW-GI group may have demonstrated augmented metabolic flexibility due to the upregulations of both carnitines and carbon acids in the samples. The elevated glycerolipids content in the HIGH-GI group suggests a potential reduction in fatty acid oxidation due to hyperinsulinemia.

Background: This study aimed to investigate the current status and perceptions of nutrition education among sports majors and workers in Korea to provide information that can be utilized in educational curriculums of universities and other external institutions for sports nutrition education.

Methods: This study included Korean adults aged over 19 years who majored in physical education at a university. The questionnaire consisted of questions regarding demographic characteristics (10 questions), nutritional awareness (20 questions), and the General Nutrition Knowledge Questionnaire (GNKQ, 88 questions). This survey was conducted entirely online using simple random sampling, and 706 responses were included in the final data analysis. An independent sample t-test and one-way ANOVA were conducted to confirm group differences. Post hoc pairwise comparisons with a Tukey adjustment were conducted. The statistical significance level for all data was set at p < 0.05.

Results: Approximately 42% of the participants completed nutrition classes at the university and 19.4% at other institutions. The assessment of their nutritional knowledge level was 3.06   ±   1.08 points (p < 0.001) on a 5-point Likert scale, with participants who had completed nutrition classes scoring higher (p < 0.001).The GNKQ also found that participants who received nutrition classes scored higher in all sections, including the total scores (total score, p = 0.011; one section, p = 0.030; three sections, p < 0.001).

Conclusion: Nutrition is a crucial aspect that cannot be excluded from physical education. Therefore, government and university institutions must increase lecture hours and hands-on opportunities by incorporating diverse educational curricula in physical education-related departments. This approach will help create a safer and more systematic sports environment and positively impact healthcare policies.

Background: Pilates is a popular type of exercise, aimed at improving core muscle strength and endurance, core stability, and joint flexibility through a variety of whole-body exercises. Research has shown that Pilates improves body composition, muscle endurance, and joint flexibility. Adequate protein intake is a key factor in supporting the adaptive response of skeletal muscle to exercise training. However, whether protein supplementation augments the adaptations to Pilates training remains unknown. Thus, the aim of the present study was to investigate the effects of protein supplementation during Pilates training on body composition, core muscle endurance, and joint flexibility in trained women.

Methods: Nineteen Pilates-trained women (31 ± 9 y) performed 10 weeks of Pilates training using the Reformer and Cadillac apparatuses, at least 2 times per week. Participants were randomly allocated to either a placebo (n = 10) or protein supplementation group (n = 9) in a quadruple-blind (participants, intervention providers, investigators, and outcome assessors) design. Participants received 0.6 g of maltodextrin or whey protein per kg body weight daily, respectively. Habitual dietary intake was monitored throughout the study. Before and after the intervention, anthropometric measures (body weight, body mass index, waist and hip circumferences), body composition [through full-scan dual-energy X-ray absorptiometry (DXA) and multifrequency bioelectrical impedance analysis (BIA)], core muscle endurance (through the McGill's torso muscular endurance test battery), and joint flexibility (through the sit-and-reach test) were assessed. Data were analyzed by 2-way ANOVA (supplement × time) with repeated measures on time. Common DXA and BIA variables (whole-body fat and lean mass) were compared through paired Student's t tests and subjected to Pearson's correlation analysis. The level of statistical significance was set at α = 0.05.

Results: Participants received, on average, 1.3 g protein/kg body weight/day from their habitual diet. After 10 weeks of Pilates training and regardless of supplementation, body fat (assessed by BIA) and hip circumference decreased; lean mass, total water, and extracellular water (by BIA) increased; and arm lean mass, trunk bone mineral content, and trunk bone area (by DXA) increased (all p < 0.05). The common BIA and DXA variables were highly correlated (r > 0.78, p < 0.001) and did not differ pre-intervention (p > 0.1), although they differed post-intervention (p < 0.001), with BIA overestimating lean mass compared with DXA. Core muscle endurance and joint flexibility increased with training (p < 0.05), with no effect of supplementation.

Conclusion: Ten weeks of Pilates training improved core muscle endurance, joint flexibility, and aspects of body composition in healthy trained women,

Background: Low energy availability (LEA) can negatively impact athletes' physiological function and performance. This study aims to examine the prevalence of LEA in Chinese female combat athletes and monitor changes in physiological function and performance during the pre-competition period.

Method: We assessed the incidence of low energy availability (LEA) and eating disorder (ED) risks in 84 female combat athletes (judo, freestyle wrestling, and sanda) from Beijing using the Low Energy Availability in Females Questionnaire (LEAF-Q) and the Eating Disorder Examination Questionnaire (EDE-Q). From this group, 11 judo athletes who were preparing for competition were selected and divided into a low energy availability (LEA) group and a non-LEA group based on their energy availability levels. Dietary intake, training energy expenditure, body composition, resting metabolic rate, blood markers, and special judo fitness tests were monitored at 4 weeks, 2 weeks, and 0 weeks before the competition.

Results: Among the 84 athletes, 45.2% of athletes (n = 38) were at increased risk of LEA, and 21.4% of athletes (n = 18) were classified as high in eating disorder risk. There were no significant differences in LEA and ED risk between elite and recreational athletes. Among the 11 athletes preparing for competition, 6 athletes (45.5%) were in a state of LEA at the initial stage (4 weeks before the competition), and by the competition week, all 11 athletes exhibited LEA. Additionally, athletes in the LEA group experienced significant reductions in VO₂ and resting metabolic rate at 0 week of the competition compared to 4 weeks prior (p < 0.05). Thyroid function indicators and IGF-1 levels of LEA group also significantly decreased (p < 0.05). After completing the four-week pre-competition weight loss, heart rate recovery during the special judo fitness test improved significantly in both the LEA and non-LEA groups (p < 0.05).

Conclusion: The current study identified a risk of LEA among Chinese female combat sport athletes, with no significant difference in the prevalence of LEA between elite and recreational athletes. It is essential for Chinese coaches and sports medicine staff to implement LEA-related nutritional education across all performance levels. Moreover, preventive measures during training are recommended to mitigate the impact of LEA on physiological function during the pre-competition weight loss phase.

Position Statement: The International Society of Sports Nutrition (ISSN) presents this position based on a critical examination of the literature surrounding the effects of long-chain omega-3 polyunsaturated fatty acid (ω-3 PUFA) supplementation on exercise performance, recovery, and brain health. This position stand is intended to provide a scientific foundation for athletes, dietitians, trainers, and other practitioners regarding the effects of supplemental ω-3 PUFA in healthy and athletic populations. The following conclusions represent the official position of the ISSN: Athletes may be at a higher risk for ω-3 PUFA insufficiency.Diets rich in ω-3 PUFA, including supplements, are effective strategies for increasing ω-3 PUFA levels.ω-3 PUFA supplementation, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), has been shown to enhance endurance capacity and cardiovascular function during aerobic-type exercise.ω-3 PUFA supplementation may not confer a muscle hypertrophic benefit in young adults.ω-3 PUFA supplementation in combination with resistance training may improve strength in a dose- and duration-dependent manner.ω-3 PUFA supplementation may decrease subjective measures of muscle soreness following intense exercise.ω-3 PUFA supplementation can positively affect various immune cell responses in athletic populations.Prophylactic ω-3 PUFA supplementation may offer neuroprotective benefits in athletes exposed to repeated head impacts.ω-3 PUFA supplementation is associated with improved sleep quality.ω-3 PUFA are classified as prebiotics; however, studies on the gut microbiome and gut health in athletes are currently lacking.