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This review of the exercise genomics literature encompasses the highest-quality articles published in 2015 across seven broad topics: physical activity behavior, muscular strength and power, cardiorespiratory fitness and endurance performance, body weight and adiposity, insulin and glucose metabolism, lipid and lipoprotein metabolism, and hemodynamic traits. One study used a quantitative trait locus for wheel running in mice to identify single nucleotide polymorphisms (SNPs) in humans associated with physical activity levels. Two studies examined the association of candidate gene ACTN3 R577X genotype on muscular performance. Several studies examined gene-physical activity interactions on cardiometabolic traits. One study showed that physical inactivity exacerbated the body mass index (BMI)-increasing effect of an FTO SNP but only in individuals of European ancestry, whereas another showed that high-density lipoprotein cholesterol (HDL-C) SNPs from genome-wide association studies exerted a smaller effect in active individuals. Increased levels of moderate-to-vigorous-intensity physical activity were associated with higher Matsuda insulin sensitivity index in PPARG Ala12 carriers but not Pro12 homozygotes. One study combined genome-wide and transcriptome-wide profiling to identify genes and SNPs associated with the response of triglycerides (TG) to exercise training. The genome-wide association study results showed that four SNPs accounted for all of the heritability of △TG, whereas the baseline expression of 11 genes predicted 27% of △TG. A composite SNP score based on the top eight SNPs derived from the genomic and transcriptomic analyses was the strongest predictor of ΔTG, explaining 14% of the variance. The review concludes with a discussion of a conceptual framework defining some of the critical conditions for exercise genomics studies and highlights the importance of the recently launched National Institutes of Health Common Fund program titled "Molecular Transducers of Physical Activity in Humans."

This is the annual review of the exercise genomics literature in which we report on the highest quality papers published in 2014. We identified a number of noteworthy papers across a number of fields. In 70-89 yr olds, only 19% of angiotensin-converting enzyme (ACE) II homozygotes exhibited significant improvement in gait speed in response to a yearlong physical activity program compared to 30% of ACE D-allele carriers. New studies continue to support the notion that the genetic susceptibility to obesity, as evidenced by a genomic risk score (GRS; based on multiple single nucleotide polymorphisms), is attenuated by 40%-50% in individuals who are physically active, compared to those who are sedentary. One study reported that the polygenic risk for hypertriglyceridemia was reduced by 30%-40% in individuals with high cardiorespiratory fitness. One report showed that there was a significant interaction of a type 2 diabetes GRS with physical activity, with active individuals having the lowest risk of developing diabetes. The protective effect of physical activity was most pronounced in the low GRS tertile (hazard ratio, 0.82). The interaction observed with the diabetes GRS seemed to be dependent on a genetic susceptibility to insulin resistance and not insulin secretion. A significant interaction between PPARα sequence variants and physical activity levels on cardiometabolic risk was observed, with higher activity levels associated with lower risk only in carriers of specific genotypes and haplotypes. The review concludes with a discussion of the importance of replication studies when very large population or intervention discovery studies are not feasible or are cost prohibitive.

The most significant and scientifically sound articles in exercise genomics that were published in 2013 are reviewed in this report. No article on the genetic basis of sedentary behavior or physical activity level was identified. A calcineurin- and alpha actinin-2-based mechanism has been identified as the potential molecular basis for the observed lower muscular strength and power in alpha actinin-3-deficient individuals. Although baseline muscle transcriptomic signatures were found to be associated with strength training-induced muscle hypertrophy, no predictive genomic variants could be identified as of yet. One study found no clear evidence that the inverse relation between physical activity level and incident CHD events was influenced by 58 genomic variants clustered into four genetic scores. Lower physical activity level in North American populations may be driving the apparent risk of obesity in fat mass- and obesity-associated gene (FTO)-susceptible individuals compared with more active populations. Two large studies revealed that common genetic variants associated with baseline levels of plasma HDL cholesterol and triglycerides are not clear predictors of changes induced by interventions focused on weight loss, diet, and physical activity behavior. One large study from Japan reported that a higher fitness level attenuated the arterial stiffness-promoting effect of the Ala54 allele at the fatty acid binding protein 2 locus, which is a controversial finding because previous studies have suggested that Thr54 was the risk allele. Using transcriptomics to generate genomic targets in an unbiased manner for subsequent DNA sequence variants studies appears to be a growing trend. Moreover, exercise genomics is rapidly embracing gene and pathway analysis to better define the underlying biology and provide a foundation for the study of human variation.

This review of the exercise genomics literature emphasizes the highest quality articles published in 2011. Given this emphasis on the best publications, only a small number of published articles are reviewed. One study found that physical activity levels were significantly lower in patients with mitochondrial DNA mutations compared with controls. A two-stage fine-mapping follow-up of a previous linkage peak found strong associations between sequence variation in the activin A receptor, type-1B (ACVRIB) gene and knee extensor strength, with rs2854464 emerging as the most promising candidate polymorphism. The association of higher muscular strength with the rs2854464 A allele was confirmed in two separate cohorts. A study using a combination of transcriptomic and genomic data identified a comprehensive map of the transcriptomic features important for aerobic exercise training-induced improvements in maximal oxygen consumption, but no genetic variants derived from candidate transcripts were associated with trainability. A large-scale de novo meta-analysis confirmed that the effect of sequence variation in the fat mass and obesity-associated (FTO) gene on the risk of obesity differs between sedentary and physically active adults. Evidence for gene-physical activity interactions on type 2 diabetes risk was found in two separate studies. A large study of women found that physical activity modified the effect of polymorphisms in the lipoprotein lipase (LPL), hepatic lipase (LIPC), and cholesteryl ester transfer protein (CETP) genes, identified in previous genome-wide association study reports, on HDL cholesterol. We conclude that a strong exercise genomics corpus of evidence would not only translate into powerful genomic predictors but also have a major effect on exercise biology and exercise behavior research.

Individuals with insulin resistance and low cardiorespiratory fitness are frequently found to have an increased waist circumference and high exercise blood pressure. We tested the hypothesis that the relationships among insulin resistance, low cardiorespiratory fitness, and increased exercise blood pressure may be mediated by an elevated waist circumference. This study included 317 apparently healthy men and women (mean age: 34.8±12.8 years; mean body mass index: 26.1±5.2 kg/m(2)). Exercise blood pressure values were measured using a submaximal ergometer test evaluating physical working capacity. Plasma insulin and glucose levels were measured during a 3-hour oral glucose tolerance test. Multivariate regression analyses showed that waist circumference accounted for 32.8% (P<0.0001) and 45.1% (P<0.0001) of the variance in exercise systolic blood pressure in men and women, respectively. Participants were classified into tertiles according to either insulin response, measured during the oral glucose tolerance test, or fitness levels and then further subdivided into 2 subgroups using sex-specific waist circumference thresholds. Individuals with an increased waist circumference (≥94 cm and ≥80 cm for men and women, respectively) had higher exercise systolic blood pressure compared with individuals with low waist circumference, irrespective of their level of insulin resistance (10.6 versus 6.8, 12.2 versus 7.7, and 13.2 versus 8.7 mm Hg/metabolic equivalent, respectively, for the low, intermediate, and high tertiles; P<0.05) or fitness levels (13.1 versus 8.2, 12.0 versus 7.9, and 10.6 versus 7.1 mm Hg/metabolic equivalent, respectively, for the low, intermediate, and high tertiles; P<0.05). Individuals with a higher waist circumference have elevated exercise systolic blood pressure, regardless of their insulin sensitivity or level of cardiorespiratory fitness.

Context: Both excess visceral adipose tissue (VAT) and low cardiorespiratory fitness (CRF) levels are associated with a deteriorated cardiometabolic risk profile., Objective: The aim of the study was to examine the respective contributions of changes in VAT accumulation vs. changes in CRF to 6-yr longitudinal changes in cardiometabolic risk markers., Design, Settings, and Participants: We conducted a prospective, population-based study with an average follow-up of 5.9 ± 0.8 yr. We followed 132 middle-aged participants from the Quebec Family Study (mean age, 35.3 ± 13.9 yr). VAT was measured by computed tomography, whereas the level of CRF was assessed by a submaximal physical working capacity test at baseline and at follow-up. A complete cardiometabolic risk profile, including systolic and diastolic blood pressure, fasting glucose and insulin levels, C-reactive protein (n = 72), as well as a standard lipoprotein-lipid profile, was obtained at baseline and at follow-up., Main Outcome Measures: We measured changes in CRF, VAT, and cardiometabolic risk profile over 6 yr., Results: After adjusting for age and sex, 6-yr changes in VAT were negatively correlated with changes in CRF (r = -0.38; P < 0.001). In a multivariate model that included age, sex, changes in VAT, changes in CRF, as well as baseline levels of the above cardiometabolic risk factors, 6-yr changes in VAT were the most important predictor of the change in the metabolic syndrome score (R(2) = 13.2%; P < 0.001). Adding 6-yr changes in CRF levels significantly improved the predictability of the model (R(2) = 19.7%; P = 0.002)., Conclusions: Changes in both VAT and CRF levels observed over 6 yr are associated with changes in parameters of the lipoprotein-lipid profile, glucose-insulin homeostasis, and inflammatory markers. Thus, maintaining a low level of VAT and a high level of CRF are important targets for maintenance of cardiometabolic health.

This review of the exercise genomics literature emphasizes the strongest articles published in 2010 as defined by sample size, quality of phenotype measurements, quality of the exercise program or physical activity exposure, study design, adjustment for multiple testing, quality of genotyping, and other related study characteristics. One study on voluntary running wheel behavior was performed in 448 mice from 41 inbred strains. Several quantitative trait loci for running distance, speed, and duration were identified. Several studies on the alpha-3 actinin (ACTN3) R577X nonsense polymorphism and the angiotensin-converting enzyme (ACE) I/D polymorphism were reported with no clear evidence for a joint effect, but the studies were generally underpowered. Skeletal muscle RNA abundance at baseline for 29 transcripts and 11 single nucleotide polymorphisms (SNPs) were both found to be predictive of the V˙O2max response to exercise training in one report from multiple laboratories. None of the 50 loci associated with adiposity traits are known to influence physical activity behavior. However, physical activity seems to reduce the obesity-promoting effects of at least 12 of these loci. Evidence continues to be strong for a role of gene-exercise interaction effects on the improvement in insulin sensitivity after exposure to regular exercise. SNPs in the cAMP-responsive element binding position 1 (CREB1) gene were associated with training-induced HR response, in the C-reactive protein (CRP) gene with training-induced changes in left ventricular mass, and in the methylenetetrahydrofolate reductase (MTHFR) gene with carotid stiffness in low-fit individuals. We conclude that progress is being made but that high-quality research designs and replication studies with large sample sizes are urgently needed., (© 2011 by the American College of Sports Medicine)

An annual review publication of the most significant articles in exercise, fitness, and performance genomics begins with this article, which covers 2 yr, 2008 and 2009. The review emphasizes the strongest articles as defined by sample size, quality of phenotype measurements, quality of the exercise program or physical activity exposure, study design, adjustment for multiple testing, quality of genotyping, and other related study characteristics. With this avowed focus on the highest quality articles, only a small number of published articles are reviewed. Among the most significant findings reported here are a brief overview of the first genome-wide association study of the genetic differences between exercisers and nonexercisers. In addition, the latest results on the actinin alpha 3 (ACTN3) R577X nonsense polymorphism are reviewed, emphasizing that no definitive conclusion can be reached at this time. Recent studies that have dealt with mitochondrial DNA haplogroups and endurance performance are described. Published reports indicating that physical activity may attenuate the effect of the fat mass and obesity associated (FTO) gene risk allele on body mass index are reviewed. Articles that have tested the contributions of specific genes to the response of glucose and insulin metabolism traits to regular exercise or physical activity level are considered and found to be generally inconclusive at this stage. Studies examining ethnic differences in the response of blood lipids and lipoproteins to exercise training cannot unequivocally relate these to apolipoprotein E (APOE) genotypes. Hemodynamic changes with exercise training were reported to be associated to sequence variation in kinesin heavy chain (KIF5B), but no replication study is available as of yet. We conclude from this first installment that exercise scientists need to prioritize high-quality research designs and that replication studies with large sample sizes are urgently needed.

The objective of the present study was to determine the respective contributions of visceral adipose tissue (AT) accumulation and cardiorespiratory fitness to variation of inflammatory markers in men and women. Circulating levels of C-reactive protein, tumor necrosis factor-alpha, interleukin-6, and adiponectin were obtained with visceral AT (computed tomography) and fitness (physical working capacity test) levels in a sample of healthy men (n = 120) and women (n = 152) covering a wide range of adiposity. An inflammation score was developed based on gender-specific percentile values of each inflammatory marker (0 or 1), which yielded a score ranging from 0 (low) to 4 (high). Visceral AT was positively associated with C-reactive protein and interleukin-6 levels (r > or =0.35, p <0.0001), but negatively associated with adiponectin (r = -0.29, p < or =0.0003) after adjustment for fitness. After adjusting for visceral AT, fitness was not associated with variation in inflammatory markers in women and only with adiponectin in men (r = -0.20, p = 0.03). In participants with low visceral AT (<130 cm(2) for men and <100 cm(2) for women), prevalences of participants with an increased inflammation score were 23.9% and 28.0%, respectively, for participants with high and low fitness, whereas in subjects with increased visceral AT, prevalences of a high inflammation score were 60.0% and 61.7%, respectively, for participants with high and low fitness. In conclusion, these results suggest that the previously reported association between poor fitness and low-grade inflammation may be largely attributable to increased visceral AT accumulation and its associated state of insulin resistance, conditions frequently observed in subjects with poor cardiorespiratory fitness.

Individuals with poor cardiorespiratory fitness have higher blood pressure than fit individuals. Individuals with low fitness levels also tend to be characterized by higher visceral adiposity compared with physically fit individuals. We tested the hypothesis that the relationship between low fitness and elevated blood pressure could be related, at least in part, to the higher level of visceral adipose tissue often found among unfit individuals. This study included 407 asymptomatic, nondiabetic participants. Visceral adipose tissue was assessed by computed tomography, and fitness was measured by a progressive submaximal physical working capacity test. Participants in the highest visceral adipose tissue tertile showed the highest systolic and diastolic blood pressures, whereas participants in the highest fitness tertile had the lowest blood pressure values (P<0.001). When participants were classified into fitness tertiles and then subdivided on the basis of visceral adipose tissue (high versus low), participants with a high visceral adipose tissue had higher systolic and diastolic blood pressure values (P=0.01), independent of their fitness category. Linear regression analyses showed that age and visceral adipose tissue, but not fitness, predicted systolic blood pressure (r(2)=0.11 [P<0.001], 0.12 [P<0.001], and 0.01 [P value nonsignificant], for age, visceral adipose tissue, and fitness, respectively) and diastolic blood pressure (r(2)=0.17 [P<0.001], 0.14 [P<0.001], and 0.01 [P value nonsignificant], for age, visceral adipose tissue, and fitness, respectively). Individuals with high visceral adipose tissue levels have higher blood pressure, independent of their fitness. Visceral adipose tissue may represent an important clinical target in the management of elevated blood pressure.

This update of the human gene map for physical performance and health-related fitness phenotypes covers the research advances reported in 2006 and 2007. The genes and markers with evidence of association or linkage with a performance or a fitness phenotype in sedentary or active people, in responses to acute exercise, or for training-induced adaptations are positioned on the map of all autosomes and sex chromosomes. Negative studies are reviewed, but a gene or a locus must be supported by at least one positive study before being inserted on the map. A brief discussion on the nature of the evidence and on what to look for in assessing human genetic studies of relevance to fitness and performance is offered in the introduction, followed by a review of all studies published in 2006 and 2007. The findings from these new studies are added to the appropriate tables that are designed to serve as the cumulative summary of all publications with positive genetic associations available to date for a given phenotype and study design. The fitness and performance map now includes 214 autosomal gene entries and quantitative trait loci plus seven others on the X chromosome. Moreover, there are 18 mitochondrial genes that have been shown to influence fitness and performance phenotypes. Thus,the map is growing in complexity. Although the map is exhaustive for currently published accounts of genes and exercise associations and linkages, there are undoubtedly many more gene-exercise interaction effects that have not even been considered thus far. Finally, it should be appreciated that most studies reported to date are based on small sample sizes and cannot therefore provide definitive evidence that DNA sequence variants in a given gene are reliably associated with human variation in fitness and performance traits.

Background: It has been suggested that overweight and obese individuals with an adequate level of cardiorespiratory fitness (CRF), the so-called fat and fit, are at reduced risk of coronary heart disease and type 2 diabetes mellitus., Methods: To determine whether individuals with low CRF have more visceral adipose tissue (AT) accumulation compared with individuals with high CRF and to verify whether low CRF is associated with a poorer metabolic profile, we performed a cross-sectional study of 169 asymptomatic men without diabetes mellitus (mean +/- SD body mass index [calculated as weight in kilograms divided by height in meters squared], 25.9 +/- 4.4; and mean +/- SD age, 37.1 +/- 14.0 years). Abdominal AT accumulation, CRF, and indexes of plasma glucose-insulin homeostasis and of the lipoprotein-lipid profile were measured., Results: More visceral AT accumulation was observed among men in the lowest tertile of CRF compared with men in the highest tertile of CRF (mean +/- SD, 139.6 +/- 70.2 cm2 vs 74.7 +/- 41.6 cm2; P < .001). Overall, the plasma lipoprotein-lipid profiles were more favorable in men with a high CRF compared with individuals with a low CRF, as men with a low CRF had higher triglyceride (mean +/- SD, 161 +/- 73 mg/dL vs 99 +/-45 mg/dL; P < .001) and apolipoprotein B (mean +/- SD, 106 +/- 23 mg/dL vs 89 +/- 24 mg/dL; P < .009) levels and an increased total cholesterol-high-density lipoprotein cholesterol ratio (mean +/- SD, 5.27 +/- 1.00 vs 3.96 +/- 1.17; P = .002) than men with high CRF. After matching individuals with similar body mass index values but with high or low CRF, men with low CRF were characterized by more visceral AT accumulation than men with high CRF (mean +/- SD, 114.4 +/- 59.9 cm2 vs 87.8 +/- 49.1 cm2; P < .007) and by a poorer metabolic profile. However, when matched for visceral AT accumulation, such differences were no longer statistically significant., Conclusion: This study underlines the importance of visceral AT accumulation in the previously reported association between CRF and metabolic complications predictive of coronary heart disease and type 2 diabetes mellitus.

The current review presents the 2005 update of the human gene map for physical performance and health-related fitness phenotypes. It is based on peer-reviewed papers published by the end of 2005. The genes and markers with evidence of association or linkage with a performance or fitness phenotype in sedentary or active people, in adaptation to acute exercise, or for training-induced changes are positioned on the genetic map of all autosomes and the X chromosome. Negative studies are reviewed, but a gene or locus must be supported by at least one positive study before being inserted on the map. By the end of 2000, in the early version of the gene map, 29 loci were depicted. In contrast, the 2005 human gene map for physical performance and health-related phenotypes includes 165 autosomal gene entries and QTL, plus five others on the X chromosome. Moreover, there are 17 mitochondrial genes in which sequence variants have been shown to influence relevant fitness and performance phenotypes. Thus, the map is growing in complexity. Unfortunately, progress is slow in the field of genetics of fitness and performance, primarily because the number of laboratories and scientists focused on the role of genes and sequence variations in exercise-related traits continues to be quite limited.

We began this series in 2000 with the aim of making available in an easily accessible format all the advances on the genetic basis of a large family of exercise-related traits. The current review presents the 2004 update of the human gene map for physical performance and health-related fitness phenotypes. It is based on peer-reviewed papers published by the end of 2004. The genes and markers with evidence of association or linkage with a performance or fitness phenotype in sedentary or active people, in adaptation to acute exercise, or for training-induced changes are positioned on the genetic map of all autosomes and the X chromosome. Negative studies are reviewed but a gene or locus must be supported by at least one positive study before being inserted on the map. One new feature is that we have incorporated the genes whose sequence variants have been associated with either the level of physical activity or indicators of sedentarism. By the end of 2000, in the early version of the gene map, 29 loci were depicted. In contrast, the 2004 human gene map for physical performance and health-related phenotypes includes 140 autosomal gene entries and quantitative trait loci, plus four on the X chromosome. Moreover, there are 16 mitochondrial genes in which sequence variants have been shown to influence relevant fitness and performance phenotypes. Thus, the map is growing in complexity and progress is being made. The number of laboratories and scientists concerned by the role of genes and sequence variations in exercise-related traits is rising. But exercise science and sports medicine is generally lagging behind in terms of utilizing the advances in genetic and genomic technologies.

This review presents the 2003 update of the human gene map for physical performance and health-related fitness phenotypes. It is based on peer-reviewed papers published by the end of 2003 and includes association studies with candidate genes, genome-wide scans with polymorphic markers, and single-gene defects causing exercise intolerance to variable degrees. The genes and markers with evidence of association or linkage with a performance or fitness phenotype in sedentary or active people, in adaptation to acute exercise, or for training-induced changes are positioned on the genetic map of all autosomes and the X chromosome. Negative studies are reviewed but a gene or locus must be supported by at least one positive study before being inserted on the map. By the end of 2000, 29 loci were depicted on the first edition of the map. In contrast, the 2003 human gene map for physical performance and health-related phenotypes includes 109 autosomal gene entries and QTL, plus two on the X chromosome. Moreover, there are 15 mitochondrial genes in which sequence variants have been shown to influence relevant fitness and performance phenotypes.

This review presents the 2002 update of the human gene map for physical performance and health-related phenotypes. It is based on peer-reviewed papers published by the end of 2002 and includes association studies with candidate genes, genome-wide scans with polymorphic markers, and single gene defects causing exercise intolerance to variable degrees. The genes and markers with evidence of association or linkage with a performance or fitness phenotype in sedentary or active people, in adaptation to acute exercise, or for training-induced changes are positioned on the genetic map of all autosomes and the X chromosome. Negative studies are reviewed, but a gene or locus must be supported by at least one positive study before being inserted on the map. By the end of 2000, 29 loci were depicted on the map. The 2001 map includes 71 loci on the autosomes and two on the X chromosome. In contrast, the 2002 human gene map for physical performance and health-related phenotypes includes 90 gene entries and QTL, plus two on the X chromosome. To all these loci, one must add 14 mitochondrial genes in which sequence variants have been shown to influence relevant fitness and performance phenotypes.

This review presents the 2001 update of the human gene map for physical performance and health-related phenotypes. It is based on scientific papers published by the end of 2001. Association studies with candidate genes, genome-wide scans with polymorphic markers, and single gene defects causing exercise intolerance to variable degrees are included. The genes and markers with evidence of association or linkage with a performance or fitness phenotype in sedentary or active people, in adaptation to acute exercise or for training-induced changes are positioned on the genetic map of all autosomes and the X chromosome. Negative studies are reviewed, but a gene or locus must be supported by at least one positive study before being inserted on the map. By the end of 2000, there were 29 loci depicted on the map. The 2001 map includes 71 loci on the autosomes and two on the X chromosome. Among these genes or markers, 24 are from prior publications on exercise intolerance and four relate to other pathologies. Finally, 13 sequence variants in mitochondrial DNA have been shown to influence relevant fitness and performance phenotypes.

The main aim of this study was to evaluate the effects of Na intake and cardiorespiratory fitness (CRF) on body composition. The study was also intended to assess whether Na intake and/or CRF mediate the genetic susceptibility to obesity. Analyses were performed on a sample of 526 adult participants from the Quebec Family Study for whom a complete data set was available for nutrient and energy intake, CRF and body composition variables. The effects of Na, CRF and their interaction were analysed by comparing sex-specific tertiles using general linear mixed models. In both males and females, we observed a significant effect of Na intake and CRF on all body composition variables. However, in females only, we found that the effect of Na intake on body composition variables varies according to CRF level such that high Na intake was associated with increased body fatness, but only in females with low CRF. This interaction effect remained significant after statistical adjustment for total sugar, fat and energy intake. Using mediation analysis, we also found Na intake and CRF to be significant mediators of the relationship between a polygenic risk score of obesity based on > 500 000 genetic variants and BMI or waist circumference. In conclusion, the current study shows that Na intake influences body composition via mechanisms that interact with aerobic fitness, especially in females. Furthermore, both Na intake and CRF seem to be involved in the expression of the genetic susceptibility to obesity. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the association between net mechanical efficiency (NME) and body composition and glycemic profile, in middle-aged (38.3 ± 14.3 years) participants from the Quebec Family Study (QFS). Analyses were completed on a sample of 605 participants (271 males and 334 females) who performed a submaximal exercise test on an ergometer consisting of three consecutive 6-min workloads at increasing intensity during which respiratory gas exchange was assessed. The calculation of NME [power output/ (vO2-vO2seated before exercise)] was based on the values of the last 3 min of the first workload at a targeted power output of 30 W. Correlations between NME and dependent variables were computed separately in males and females. Associations between NME and body composition and glucose–insulin variables were assessed by comparing groups of subjects categorized in sex-specific tertiles of NME after adjustments for age. Significant negative correlations were observed between NME and body composition and glycemic profile in both sexes. Comparison across tertiles showed that individuals with high NME displayed more favorable adiposity and glycemic profiles. These differences remained significant after further adjustments for participation in vigorous physical activity, cardiorespiratory fitness, and mean exercise respiratory exchange ratio whereas most differences in glucose–insulin variables became non-significant after further adjustment for percent body fat. QFS familial data indicate that the heritability of NME reaches about 30%. In conclusion, the results of this study show that beyond aerobic fitness and physical activity-participation, mechanical efficiency is an additional activity-related variable that is independently associated with variations in body composition and glycemic profile. [ABSTRACT FROM AUTHOR]

Physical activity is favourably considered for its effect on metabolic fitness and body composition. This observation is generally supported by observational studies and is concordant with endurance-trained individuals' metabolic and morphological profiles. However, in some contexts, the measurement of physical activity habits may not provide an adequate representation of its benefits. In this paper, we review relevant literature on the respective effects of fitness and physical activity on anthropometric and metabolic variables and the informative potential of a classification based on aerobic fitness and activity indicators. The relevance to defining a profile based on both fitness and activity is reinforced by data from the Quebec Family Study showing that, in both men and women, "fit-active" individuals displayed a much more favourable morphological and metabolic profile than "unfit-inactive" individuals. Moreover, these benefits seemed to be more related to variations in fitness than in physical activity. In summary, evidence suggests that a profile combining information on aerobic fitness and physical activity may better reflect the lifelong impact of physical activity on body composition and health. Novelty: The fit-active profile better reflects the long-term benefits of vigorous physical activity participation on health. The reported benefits seem to be more related to variations in aerobic fitness than to those in physical activity. [ABSTRACT FROM AUTHOR]

Reviews of several articles on exercise genomics are presented which includes the reports "Exercise and Diet Affect Quantitative Trait Loci for Body Weight and Composition Traits in an Advanced Intercross Population of Mice, by L. J. Leamy, S. A. Kelly, K. Hua, and D. Pomp in a 2012 issue of the journal "Physiological Genomics," "Variation in the Uncoupling Protein 2 and 3 Genes and Human Performance," by S. S. Dhamrait, A. G. Williams, and S. H. Day et al. in a 2012 issue of the "Journal of Applied Physiology," and "Knock-in Mice for the R50X Mutation in the PYGM Gene Present With McArdle Disease," by G. Nogales-Gadea, T. Pinos, and A. Lucia et al. in a 2012 issue of the journal "Brain."

Background: The promotion of physical activity among an overweight/obese population is an important challenge for clinical practitioners and researchers. In this regard, completing a questionnaire on cognitions could be a simple and easy strategy to increase levels of physical activity. Thus, the aim of the present study was to test the effect of completing a questionnaire based on the Theory of Planned Behavior (TPB) on the level of physical activity. Methods: Overall, 452 overweight/obese adults were recruited and randomized to the experimental or control group. At baseline, participants completed a questionnaire on cognitions regarding their participation in leisuretime physical activity (experimental condition) versus a questionnaire on fruit and vegetable consumption (control condition). The questionnaires assessed the TPB variables that are beliefs, attitude, norm, perception of control, intention and a few additional variables from other theories. At three-month follow-up, leisure-time physical activity was self-reported by means of a short questionnaire. An analysis of covariance with baseline physical activity level as covariate was used to verify the effect of the intervention. Results: At follow-up, 373 participants completed the leisure-time physical activity questionnaire. The statistical analysis showed that physical activity participation was greater among participants in the experimental condition than those in the control condition (F(1,370) = 6.85, p = .009, d = 0.20). Conclusions: Findings indicate that completing a TPB questionnaire has a significant positive impact on subsequent participation in physical activity. Consequently, asking individuals to complete such a questionnaire is a simple, inexpensive and easy strategy to increase the level of physical activity among overweight/obese adults. [ABSTRACT FROM AUTHOR]

Homozygosity for a premature stop codon at amino acid position 577 in the alpha-actinin-3 (ACTN3) gene leads to α-actinin-3 deficiency. This genotype is observed in approximately 18% of Caucasians. The ACTN3 R577X polymorphism has been previously associated with indicators of physical performance in several, but not all, studies. We examined the prevalence of R577X (rs1815739) and two additional haplotype tagging single nucleotide polymorphisms (htSNPs) of the ACTN3 gene (rs1791690 and rs2275998) in the Genathlete study comprising 316 male elite endurance athletes ([Vdot]O2max 79.0 ± 3.5 ml · kg-1 · min-1; mean ± s) from North America, Finland, and Germany and 304 sedentary controls ([Vdot]O2max 40.1 ± 7.0 ml · kg-1 · min-1) matched by country of origin. The distribution of genotype and allele frequencies between the two groups was tested by Pearson chi-square and/or Fischer exact test. The prevalence of the 577X homozygote genotype was similar in endurance athletes and controls (20% and 17.5%, respectively). The resulting odds ratio for endurance performance in 577X homozygotes compared with 577R-allele carriers was 1.24 (95%CI 0.82-1.87, P = 0.3). The genotype distribution of the two htSNPs and haplotype frequencies did not differ significantly between athletes and controls. In conclusion, our findings indicate that ACTN3 R577X and other SNPs in ACTN3 are not genetic determinants of endurance performance in Caucasian males. [ABSTRACT FROM AUTHOR]

Background: Intention is a key determinant of action. However, there is a gap between intention and behavioural performance that remains to be explained. Therefore, the aim of this study was to identify moderators of the intention-behaviour and perceived behavioural control (PBC)-behaviour relationships for leisure-time physical activity. Method: This was tested in reference to Ajzen's Theory of Planned Behaviour. A sample of 300 volunteers, 192 women and 108 men, aged 18 to 55, participated in the study. At baseline, the participants completed a self-administrated psychosocial questionnaire assessing Ajzen's theory variables (i.e., intention and perceived behavioural control). The behavioural measure was obtained by mail three months later. Results: Multiple hierarchical regression analyses indicated that age and annual income moderated the intention-behaviour and PBC-behaviour relationships. However, in the final model predicting behaviour (R² = .46), only the interaction term of PBC by annual income (β = .24, p = 0.0003) significantly contributed to the prediction of behaviour along with intention (β = .49, p = 0.0009) and past behaviour (β = .44, p < 0.0001). Conclusion: Physical activity promotion programs would benefit not only from focusing on increasing the intention of low intenders, but also from targeting factors that moderate the perceived behavioural control-behaviour relationships. [ABSTRACT FROM AUTHOR]

Abstract: The Arg16Gly single nucleotide polymorphism of the human β 2-adrenoceptor (ADRB2) gene was evaluated in a case-control study that included 313 white male elite endurance athletes and 297 white male sedentary controls (SCs) recruited in a multicenter project from North America, Finland, and Germany. The groups were matched by country of origin. The elite endurance athletes were required to have a maximum oxygen uptake ≥75 mL·kg−1·min−1 (mean [SD], 79.0 [3.5]), whereas SC subjects had to be sedentary with a measured maximum oxygen uptake ≤50 mL·kg−1·min−1 (40.1 [7.0]). Polymerase chain reaction technique was used to amplify the single nucleotide polymorphism–containing region in codon 16 of the ADRB2 gene. ADRB2 genotypes were in Hardy-Weinberg equilibrium in both groups. Genotypes did not differ between countries or sports of the athletes. The χ 2 analysis for the genotype distribution showed a significant difference between the 2 cohorts (P = .030), suggesting a positive association between the tested Arg16Gly polymorphism and endurance performance. Comparing carriers vs non-carriers for the 2 alleles, an excess of Gly allele carriers was seen in the SC group (P = .009), indicating an unfavorable effect of the Gly allele with respect to the performance status. In conclusion, we found suggestive evidence that the Arg16Gly polymorphism in the gene encoding for the β 2-adrenergic receptor may associate with endurance performance status in white men. [Copyright &y& Elsevier]

The purpose of this study was to assess the association between the international overweight cutoffs for children and youth and coronary heart disease risk factors. The sample included 410 boys and 337 girls 9–18 years of age from the Que´bec Family Study. Participants were classified as normal weight or overweight using the international BMI cutoffs, and into normal and elevated risk groups based on the 90th percentile of sex-specific age-adjusted risk factors [blood pressure, fasting total cholesterol (CHOL), LDL-C, HDL-C, CHOL/HDL-C, triglycerides, glucose, and physical work capacity]. Overweight participants had between 1.6 and 9.1 times the risk of elevated risk factors compared to normal-weight participants. Further, boys and girls with four or more risk factors were 19 and 43 times more likely to be overweight, respectively, compared to participants with no risk factors. The results add evidence that the international cutoffs are related to health risks in youth, supporting the adoption of the guidelines. [Copyright &y& Elsevier]