March 7, 2017
Gina M. Many1,5, Zachary Kendrick1, Chelsea L. Deschamps2, Courtney Sprouse1, Laura L. Tosi1, Joseph M. Devaney1, Heather Gordish-Dressman1, Whitney Barfield1, Eric P. Hoffman1, Joseph A. Houmard3, Linda S. Pescatello4, Hans J. Vogel6, Jane Shearer2,6, & Dustin S. Hittel6
1 Genetic Medicine, Children’s National Medical Center, Washington DC, USA
2 Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
3 Department of Kinesiology, East Carolina University, Greenville, North Carolina, USA
4 Department of Kinesiology, University of Connecticut; Storrs, Connecticut, USA
5 Departments of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham (UAB), Birmingham, Alabama, USA
6 Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
Inactivity and sedentary behaviours contribute to ~5.3 million deaths annually. A significant proportion of these deaths are due to complications from type 2 diabetes and the insulin resistance syndrome that precedes it. Although regular physical activity is the most effective intervention for the prevention of insulin resistance, significant variability exists in both the effectiveness of and adherence to, prescribed exercise for both fitness and health goals.
To gain insight into the genetics of exercise adherence, Hittel et al. assessed variability of single nucleotide polymorphisms (SNPs) of genes related to adrenergic receptors (SNPs ARDB1 Arg389Gly and ADRB3 Trp64Arg). SNPs are variations in a single nucleotides (DNA) that occur at a specific positions in the genome. They are the most common type of genetic variation between individuals. SNPs in adrenergic receptors are important because they are involved in the cardiovascular response to exercise (heart) as well as how an individual perceives and adheres to exercise (brain). For example, if an individual does not rapidly respond to and perceives exercise as difficult, they will be less likely to engage in regular physical activity.
In the present study, adrenergic receptor SNPs were evaluated in relation to cardiometabolic health and physical activity in a cohort of healthy young university students. Carriers of the ADRB1 Arg389Gly SNP reported reduced participation in moderate physical activity as well as increased afternoon fatigue compared to non-carriers. Furthermore, carriers of the ADRB3 Trp64Arg SNP reported decreased perception of exercise intensity (on average) than non-carriers as captured using the Borg rate of perceived exertion scale. Unexpectedly, carriers of both ADRB1 and ADRB3 SNPs, were significantly underrepresented in Kinesiology (ADRB1 29%, ADRB3 7%) students compared to Non-Kinesiology majors (ADRB1 52%, ADRB3 14%). Taken together, this evidence indicates that ARDB1 and ADRB3 polymorphisms may influence voluntary participation as well as the perception and enjoyment of physical activity. However; it is worth noting that these associations were only significant in non-kinesiology majors, suggesting that educational setting (health education) can override certain genotype-associated physical activity behaviors. Given the widespread use of direct to consumer genetic testing by both athletes and non-athletes, a practical application of our research could be to identify individuals who are polymorphic for both ADRB1 and 3 SNPs (~10% of the population) and would therefore most benefit from a personal trainer or wearable fitness monitor in order to adhere to a prescribed exercise program.
This article is a summary of an article published in Applied Physiology, Nutrition & Metabolism. If you intend to cite any information in this article, please consult the original article and cite that source. This summary was written for the Canadian Society for Exercise Physiology and it has been reviewed by the CSEP Knowledge Translation Committee.
Many, G.M., Kendrick, Z., Deschamps, C.L., Sprouse, C., Tosi, L.L., Devaney, J.M., Gordish-Dressman, H., Barfield, W., Hoffman, E.P., Houmard, J.A., Pescatello, L.S., Shearer, J., and Hittel, D.S. 2016. Genetic Characterization of Physical Activity Behaviours in University Students Enrolled in Kinesiology Degree Programs. Appl. Physiol. Nutr. Metab. 10.1139/apnm-2016-0441