The aim of the study was to identify genetic variants associated with personal best scores in Turkish track and field athletes and to compare allelic frequencies between sprint/power and endurance athletes and controls using a whole-exome sequencing (WES) approach, followed by replication studies in independent cohorts. The discovery phase involved 60 elite Turkish athletes (31 sprint/power and 29 endurance) and 20 ethnically matched controls. The replication phase involved 1132 individuals (115 elite Russian sprinters, 373 elite Russian endurance athletes (of which 75 athletes were with VO_2max measurements), 209 controls, 148 Russian and 287 Finnish individuals with muscle fiber composition and cross-sectional area (CSA) data). None of the single nucleotide polymorphisms (SNPs) reached an exome-wide significance level (p < 2.3 × 10⁻⁷) in genotype–phenotype and case–control studies of Turkish athletes. However, of the 53 nominally (p < 0.05) associated SNPs, four functional variants were replicated. The SIRT1 rs41299232 G allele was significantly over-represented in Turkish (p = 0.047) and Russian (p = 0.018) endurance athletes compared to sprint/power athletes and was associated with increased VO_2max (p = 0.037) and a greater proportion of slow-twitch muscle fibers (p = 0.035). The NUP210 rs2280084 A allele was significantly over-represented in Turkish (p = 0.044) and Russian (p = 0.012) endurance athletes compared to sprint/power athletes. The TRPM2 rs1785440 G allele was significantly over-represented in Turkish endurance athletes compared to sprint/power athletes (p = 0.034) and was associated with increased VO_2max (p = 0.008). The AGRN rs4074992 C allele was significantly over-represented in Turkish sprint/power athletes compared to endurance athletes (p = 0.037) and was associated with a greater CSA of fast-twitch muscle fibers (p = 0.024). In conclusion, we present the first WES study of athletes showing that this approach can be used to identify novel genetic markers associated with exercise- and sport-related phenotypes.

The present study aimed to examine the vitamin D receptor (VDR), rs2228570 polymorphism, and its effect on elite athletes’ performance. A total of 60 elite athletes (31 sprint/power and 29 endurance) and 20 control/ physically inactive, aged 18–35, voluntarily participated in the study. The International Association of Athletics Federations (IAAF) score scale was used to determine the performance levels of the athletes’ personal best (PB). Whole exome sequencing (WES) was performed by the genomic DNA isolated from the peripheral blood of the participants. Sports type, sex, and competitive performance were chosen as the parameters to compare within and between the groups by linear regression models. The results showed no statistically significant difference between the CC, TC, and TT genotypes within and between the groups (p > 0.05). Additionally, our results underlined that there were no statistically significant differences for the association of rs2228570 polymorphism with PBs within the groups of the (p > 0.05) athletes. The genetic profile in the selected gene was similar in elite endurance, sprint athletes, and in controls, suggesting that rs2228570 polymorphism does not determine competitive performance in the analyzed athlete cohort.

Background: Data on the genetic factors contributing to inter-individual variability in muscle fiber size are limited. Recent research has demonstrated that mice lacking the Arkadia (RNF111) N-terminal-like PKA signaling regulator 2N (Ark2n; also known as C18orf25) gene exhibit reduced muscle fiber size, contraction force, and exercise capacity, along with defects in calcium handling within fast-twitch muscle fibers. However, the role of the ARK2N gene in human muscle physiology, and particularly in athletic populations, remains poorly understood. The aim of this study was threefold: (a) to compare ARK2N gene expression between power and endurance athletes; (b) to analyze the relationship between ARK2N gene expression and muscle fiber composition; and (c) to investigate the association between the functional variant of the ARK2N gene, muscle fiber size, and sport-related phenotypes. Results: We found that ARK2N gene expression was significantly higher in power athletes compared to endurance athletes (p = 0.042) and was positively associated with the proportion of oxidative fast-twitch (type IIA) muscle fibers in untrained subjects (p = 0.017, adjusted for age and sex). Additionally, we observed that the ARK2N rs6507691 T allele, which predicts high ARK2N gene expression (p = 3.8 × 10⁻¹²), was associated with a greater cross-sectional area of fast-twitch muscle fibers in strength athletes (p = 0.015) and was over-represented in world-class strength athletes (38.6%; OR = 2.2, p = 0.023) and wrestlers (33.8%; OR = 1.8, p = 0.044) compared to controls (22.0%). Conclusions: In conclusion, ARK2N appears to be a gene specific to oxidative fast-twitch myofibers, with its functional variant being associated with muscle fiber size and strength-athlete status.

Limited number of researches exist on the relationship between PPARGC1A gene polymorphism (rs8192678) and affects the athletic performance. Thus, the present study aims to decipher any possible association of the rs8192678 polymorphism in the PPARGC1A gene with the competitive performances of Turkish elite track and field athletes. A total of 60 elite athletes (31 sprint/power and 29 endurance) and 20 control/sedentary with the ages of 18-35 voluntarily participated in the study. The International Association of Athletics Federations (IAAF) score scale was used to determine the performance levels of the personal best (PB) of the athletes. Whole exome sequencing (WES) was performed by the genomic DNA sample isolated from blood of the participants. The association between rs8192678 polymorphism and PB was examined by one-way analysis of covariance (ANCOVA) with the adjustment of sex and sport experience. According to the results, there were not any significant deviation between the wild-type (G/G), heterozygote (G/A) and homozygote (A/A) genotypes within and between the groups (p>0.05). Our results underlined that there were not any significances for association of rs8192678 polymorphism with PBs within the groups of the sprint/power and endurance athletes. However, it is recommended that similar studies be conducted with more participants to provide clearer information about the research.

Modern pentathlons impose high physiological demands on adolescent and young adult athletes, whose nutritional requirements are further increased by growth and maturation. Evidence on sports nutrition knowledge, dietary practices, supplement beliefs, and anthropometric characteristics in adolescent and young adult pentathletes remains limited. This cross-sectional study evaluated these parameters in 50 modern pentathletes aged 10–22 years (22 females, 28 males) training at the Turkish Olympic Preparation Centre. Participants completed the Nutrition for Sport Knowledge Questionnaire (NSKQ), Sport Supplement Belief Scale (SSBS), and a 24-hour dietary recall; anthropometric measurements and nutrient adequacy were also assessed. Poor nutrition knowledge was observed in 98.0% of participants. Meal skipping was reported by 44.0% of athletes. Mean energy adequacy was 72.5 ± 27.65%, carbohydrate intake was below general sports nutrition recommendations (4.07 ± 1.90 g/kg/day), and protein intake met recommendations (1.7 ± 0.73 g/kg/day). Calcium intake reached approximately 50% of recommended levels, while selenium intake in females met 40% of the Recommended Dietary Allowance (RDA) and was significantly lower than in males (p = .021). Most athletes (80.0%) were within the normal Body Mass Index (BMI) range; BMI increased with age, and females had higher body fat percentages than males. Athletes consuming no fluids during training had higher SSBS scores than those consuming sports drinks (p = .035). These findings indicate inadequate sports nutrition knowledge, suboptimal carbohydrate and calcium intake, and inconsistent hydration practices, supporting the need for structured, sport-specific nutrition education and regular monitoring.