Classical twin studies that presented heritability rates associated with performance in various sports disciplines support the value of genetics in determining the response. In addition, numerous trials involving physiological responses such as hypertrophy, energy expenditure, vasodilation, cardiac output
Gustavo Monnerat, Alex S. Maior, Marcio Tannure, Lia K.F.C. Back and Caleb G.M. Santos
Gabriel Rodríguez-Romo, Thomas Yvert, Alfonso de Diego, Catalina Santiago, Alfonso L. Díaz de Durana, Vicente Carratalá, Nuria Garatachea and Alejandro Lucia
The authors compared ACTN3 R577X genotype and allele frequencies in the majority of all-time-best Spanish judo male athletes (n = 108) and 343 ethnically matched nonathletic men. No between-groups differences were found in allele (P = .077) or genotype distributions (P = .178). Thus, the R577X polymorphism was not significantly associated with the status of being an elite judo athlete, at least in the Spanish population. The contribution of genetics to sports-related phenotype traits is undeniable with some genotypes, of which ACTN3 R577X is currently the leading candidate, partly distinguishing individuals predisposed to either endurance or power sports. However, few athletic events can be categorized as purely power or endurance based. Although genetic testing (ie, for ACTN3 R577X) is already being marketed to predict sports talent and potential of young children, its usefulness is still questionable, at least in competitive judo.
Sharon Ann Plowman
The last decade has seen a shift in emphasis from the goal of attaining physical fitness (a product) to the behavior of physical activity (a process) to achieve health benefits. A central question is whether the achievement of physical fitness (PF) is necessary or if participation in physical activity (PA) is sufficient. Three basic tenets of this shift are examined by using representative studies. They are: (1) both PA and PF will lead to health benefits; PF is simply a surrogate measure for PA, (2) the impact of genetics will be avoided if PA, not PF, is emphasized and that is desirable, and (3) it is easier to motivate “the masses” to accumulate lifestyle moderate activity than to undergo a vigorous exercise prescription. Results indicate that PA and PF might be independent risk factors, that both have a degree of genetic determination, and that participation rates for PA have changed little and remain insufficient. Both PA and PF need to be evaluated, promoted, and attained.
Peter J. Whalley, Chey G. Dearing and Carl D. Paton
. Increases in cycling performance in response to caffeine ingestion are repeatable . Nutr Res . 2012 ; 32 : 78 – 84 . PubMed ID: 22348455 doi:10.1016/j.nutres.2011.12.001 22348455 10.1016/j.nutres.2011.12.001 23. Southward K , Rutherford-Markwick K , Badenhorst C , Ali A . The role of genetics
Mohanraj Krishnan, Andrew N. Shelling, Clare R. Wall, Edwin A. Mitchell, Rinki Murphy, Lesley M.E. McCowan and John M.D. Thompson
.healthplace.2016.09.003 27771443 15. Grimm ER , Steinle NI . Genetics of eating behavior: established and emerging concepts . Nutr Rev . 2011 ; 69 ( 1 ): 52 – 60 . PubMed doi:10.1111/j.1753-4887.2010.00361.x 21198635 10.1111/j.1753-4887.2010.00361.x 16. Hill JO , Wyatt HR , Peters JC . Energy
Gaston Beunen, Martine Thomis, Maarten Peeters, Hermine H. Maes, Albrecht L. Claessens and Robert Vlietinck
The aim of this study is to quantify the genetic and environmental variation in isometric and explosive strength (power) in children and adolescents, using structural equation models. Arm pull (static strength) and vertical jump (explosive strength, power) were measured in 105 twin pairs from the Leuven Longitudinal Twin Study. Boys and girls were tested at annual intervals between 10 and 16 years and at 18 years. Path models were fitted to the observed strength characteristics and a gender heterogeneity analysis was performed at each age level. A model including additive genetic and specific environmental factors (AE-model) allowing for a difference in total phenotypic variance or in genetic/environmental variance components in boys and girls best explains both strength characteristics at most age levels. The additive genetic contribution for isometric strength varies between a2 = .44 and a2 = .83, and for explosive strength between a2 = .47 and a2 = .92, except at 16 years in males. In conclusion there is good evidence that during the growth period both static and explosive strength are under moderate to moderately strong genetic influence.
Joey C. Eisenmann and Keith Tolfrey
Sigal Ben-Zaken, Yoav Meckel, Nitzan Dror, Dan Nemet and Alon Eliakim
In recent years several genetic polymorphisms related to the GH-IGF-I axis were suggested to promote athletic excellence in endurance and power sports. We studied the presence of the C-1245T SNP (rs35767), a nucleotide substitution in the promoter region of the IGF-I gene, and the presence of the 275124A > C SNP (rs1464430), a common nucleotide substitution in the intron region of the IGF-I receptor (IGF-IR) gene in elite long and short-distance swimmers compared with nonphysically active controls. The rare T/T IGF-I polymorphism was found only in 5.3% of the long-distance swimmers, and was not found at all in the short-distance swimmers or among the control group participants. The prevalence of the IGF-I receptor AA genotype was significantly lower in the swimming group as a whole (35%) compared with the control group (46%), in particularly due to reduced frequency of the AA genotype among short-distance swimmers (26%). In contrast to previous reports in elite endurance and power track and field athletes, single nucleotide polymorphisms of the IGF-I and the IGF-IR were not frequent among elite Israeli short- and long-distance swimmers emphasizing the importance of other factors for excellence in swimming. The results also suggest that despite seemingly similar metabolic characteristics different sports disciplines may have different genetic polymorphisms. Thus, combining different disciplines for sports genetic research purposes should be done with extreme caution.
João Paulo Limongi França Guilherme and Antonio Herbert Lancha Jr.
Carnosine (β-alanyl-L-histidine), abundantly found in skeletal muscle, plays an important role during exercise, especially for high-intensity contractions. Variability in muscle carnosine content between individuals exists and may also be explained by different genetic bases, although no study has addressed the association of polymorphisms in genes related to carnosine metabolism in athletes. This study aimed to investigate the frequency of single nucleotide polymorphisms (SNPs) in the carnosinase genes (CNDP1 and CNDP2) in a large Brazilian cohort of athletes and nonathletes. Eight SNPs were compared between a representative cohort of elite athletes from Brazil (n = 908) and a paired group of nonathletes (n = 967). The athletes were stratified into three groups: endurance (n = 328), power (n = 415), and combat (n = 165). The CNDP2 rs6566810 (A/A genotype) is overrepresented in endurance athletes, but only in international-level endurance athletes. Three SNPs (CNDP2 rs3764509, CNDP2-CNDP1 rs2346061, and CNDP1 rs2887) were overrepresented in power athletes compared with nonathletes. Carriers of the minor allele had an increased odds ratio of being a power athlete. For the rs2346061, no significant difference was observed in genotype frequencies between power and combat sports athletes, but for rs2887 the power and combat groups showed an inverse genotype distribution. In conclusion, we found that minor alleles carriers for CNDP2 rs3764509 (G-allele), CNDP2-CNDP1 rs2346061 (C-allele), and CNDP1 rs2887 (A-allele) are more likely to be a power athlete. These polymorphisms may be novel genetic markers for power athletes. Furthermore, these results are suggestive of a distinct CNDP genotype for sporting development.
Erin White, Jennifer D. Slane, Kelly L. Klump, S. Alexandra Burt and Jim Pivarnik
Knowing the extent to which genetic and environmental factors influence percent body fatness (%Fat) and physical activity (PA) would be beneficial, since both are tightly correlated with future health outcomes. Thus, the purpose was to evaluate sex differences in genetic and environmental influences on %Fat and physical activity behavior in male and female adolescent twins.
Subjects were adolescent (age range 8.3 to 16.6 yr) twins. %Fat (n = 518 twins) was assessed by bioelectrical impedance analysis (BIA) and PA (n = 296 twins) was measured using 3-Day PA Recall. Each activity was converted to total MET-minutes. Univariate twin models were used to examine sex differences in genetic and environmental factors influencing %Fat and PA.
%Fat was influenced by genetic effects in both boys and girls (88% and 90%, respectively), with slightly higher heritability estimates for girls. PA was influenced solely by environmental effects for both sexes with higher shared environmental influences in boys (66%) and higher nonshared effects in girls (67%).
When developing interventions to increase PA in adolescents, it is important to consider the environment in which it takes place as it is the primary contributor to PA levels.