Agata Leońska-Duniec, Zbigniew Jastrzębski, Aleksandra Zarębska, Wojciech Smółka and Paweł Cięszczyk
The C/T polymorphism (rs17782313) mapped 188 kb downstream of the melanocortin-4 receptor gene (MC4R) shows a strong relationship with an increased body mass index (BMI) and the risk of type 2 diabetes. However, the information on polymorphism’s potential modifying effect on obesity- and metabolic-related traits achieved through training is still unknown. Therefore, we decided to check if selected body measurements observed in physically active participants would be modulated by the genotype. The genotype distribution was examined in a group of 201 Polish women measured for chosen traits before and after the completion of a 12 week moderate-intensive aerobic training program. A statistically significant relationship between the glucose level and the genotype was identified (p = 0.046). Participants with CC and CT genotypes had a higher glucose level during the entire study period compared with the TT genotype. However, our results did not confirm the relationship between the C allele and an increased BMI or other obesity-related traits. Additionally, we did not observe a near MC4R C/T polymorphism x physical activity interaction. However, our results revealed that majority of obesity-related variables changed significantly during the 12 week training program. The effect sizes (d) of these changes ranged from small to medium (d = 0.11-0.80), whereas the largest effect (d = 0.80; i.e. medium) was reported for the fat mass content (FM). We found a relationship between the near MC4R C/T polymorphism and an increased glucose level, and it is thus a candidate to influence type 2 diabetes. Interestingly, after the 12 week training program, participants with the C (risk) allele with fasting hyperglycemia had a normal glucose level. Although, this change was not statistically significant, it shows an important trend which needs further investigation.
Paweł Cięszczyk, Aleksandra Zarębska, Zbigniew Jastrzębski, Michał Sawczyn, Izabela Kozakiewicz-Drobnik, Agata Leońska-Duniec, Mariusz Kaczmarczyk, Agnieszka Maciejewska-Skrendo, Piotr Żmijewski, Grzegorz Trybek, Wojciech Smółka, Jan Pilch, Katarzyna Leźnicka, Ewelina Lulińska-Kuklik, Marek Sawczuk and Myosotis Massidda
The 5,10-methylenetetrahydrofolate reductase gene (MTHFR) A1298C polymorphic variant is a candidate to explain the individual differences in trainability and response to exercise training. Therefore, the aim of the study was to verify whether the A1298C polymorphism influenced the aerobic and anaerobic performance as well as body and mass composition in young Polish women following low-high impact aerobic exercise training. Two hundred and one women aged 21 ± 1 years (range 19–24) were included in the study. All of them completed a 12-week exercise training program and were measured for selected somatic features, aerobic capacity and cardiorespiratory fitness indices as well as peak anaerobic power and anaerobic capacity, before and after the intervention. A mixed 2 x 2 ANOVA for 20 dependent variables grouped in three categories was conducted. No significant interaction of the genotype with training for body mass and body composition variables was observed. Although, there were three significant genotype x training interactions for maximal oxygen uptake variables, regardless of body mass i.e.: for VO2max (p < 0.05), HRmax (p < 0.0001) and HRAT/HRmax (p < 0.0001). Significantly greater improvement in VO2max was gained by the CC+AC group compared to the AA genotype group. The present results support the hypothesis that individual differences in trainability are at least in part determined by the genetic component and MTHFR A1298C seems to be one of the many polymorphisms involved.