Search Results

You are looking at 1 - 10 of 16 items for :

  • "heritability" x
Clear All
Restricted access

Erin White, Jennifer D. Slane, Kelly L. Klump, S. Alexandra Burt and Jim Pivarnik

Background:

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.

Methods:

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.

Results:

%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%).

Conclusions:

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.

Restricted access

Gustavo Monnerat, Alex S. Maior, Marcio Tannure, Lia K.F.C. Back and Caleb G.M. Santos

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

Restricted access

Joey C. Eisenmann, R. Todd Bartee and Krystal D. Damori

Purpose:

The purposes of this study were (a) to describe the prevalence of participation in moderate to vigorous physical activity (MVPA) and overweight and obesity, and (b) to examine the associations between physical activity and weight status in a sample of university students from a rural university.

Methods:

Data from a representative sample of 773 (361 women, 412 men) students participating in the National College Health Assessment Survey were examined. MVPA and height and body mass were self-reported. The body-mass index (BMI) was derived and used to classify subjects as normal, overweight, or obese.

Results:

Approximately 20% of students were inactive (0 d/wk), and 23% met the recommended amount of MVPA (≥5 d/wk). Prevalence of overweight and obesity was, respectively, 35.7% and 8.5% in men and, respectively, 15.6% and 8.2% in women. Analysis of variance revealed the mean BMI was not significantly different across levels of MVPA. Odds ratios showed higher levels of MVPA were significantly associated with lower risk of obesity in men but not women.

Conclusion:

A large percentage of subjects are inactive or insufficiently active, and self-reported moderate to vigorous physical activity is significantly related to risk of obesity in men. Future studies should measure habitual physical activity or energy expenditure and body composition. Additional factors affecting obesity, such as television viewing and other sedentary behaviors, dietary intake, and heritability, should also be considered.

Restricted access

Alex V. Rowlands

. For example, the pattern of PA with age mirrors that of basal metabolic rate and is consistent across cultures and indeed other animals; boys are more active than girls, again across diverse cultures; and twin studies suggest an overall heritability estimate of around 50% for PA, analogous to the

Restricted access

Adam D.G. Baxter-Jones

after the adolescent growth spurt. Since the expected correlation between parents and offspring would be .5 if the heritability of the trait were 1.0 (the heritability of a trait is a measure of the degree of genetic control of a phenotype), it can be concluded that the population variation in height is

Restricted access

João Paulo Limongi França Guilherme, Ekaterina A. Semenova, Hirofumi Zempo, Gabriel L. Martins, Antonio H. Lancha Junior, Eri Miyamoto-Mikami, Hiroshi Kumagai, Takuro Tobina, Keisuke Shiose, Ryo Kakigi, Takamasa Tsuzuki, Noriko Ichinoseki-Sekine, Hiroyuki Kobayashi, Hisashi Naito, Oleg V. Borisov, Elena S. Kostryukova, Nikolay A. Kulemin, Andrey K. Larin, Edward V. Generozov, Noriyuki Fuku and Ildus I. Ahmetov

achievement, individual performance thresholds can be determined by our genetic makeup. Twin studies have reported moderate to high heritability estimates for maximum movement speed, as well as for other sprint and power phenotypes, 5 , 6 and so it has been proposed that elite sprint performance strongly

Restricted access

Magdalena Żegleń, Łukasz Kryst, Małgorzata Kowal and Agnieszka Woronkowicz

highly heritable aspect of physical fitness ( h 2  = 30%–65%). 27 , 33 – 35 Thus, the observed intergenerational changes regarding the dynamometric force may largely depend on genetic factors and less so on environmental conditions of development. As has already been mentioned, in the current research

Full access

Trent Stellingwerff

, 2006 ). Perspective An individual’s phenotype (weight and body composition) is determined by interactions between genetic and environmental factors, with estimates of phenotypic heritability from epidemiological studies varying between 25% and 75% ( Bouchard, 1994 ). Therefore, there will be a genetic

Restricted access

Gil Rodas, Lourdes Osaba, David Arteta, Ricard Pruna, Dolors Fernández and Alejandro Lucia

have small effect sizes, which underline the polygenic nature of tendinopathy, and clearly affect the prediction performance of the models. The estimated heritability for muscle strength and muscle mass, assessed by twin and family studies, varies from 31% to 78%, with large differences between muscle

Restricted access

Rebecca M. Dagger, Ian G. Davies, Kelly A. Mackintosh, Genevieve L. Stone, Keith P. George, Stuart J. Fairclough and Lynne M. Boddy

.2012.0152 10.1089/met.2012.0152 23758076 24. Hopkins ND , Stratton G , Maia J , Tinken TM , Graves LE , Cable TN , Green DJ . Heritability of arterial function, fitness, and physical activity in youth: a study of monozygotic and dizygotic twins . J Pediatr . 2010 ; 157 : 943 – 8