Exercise is a major factor in leading a healthy lifestyle, providing both physical and mental health benefits. However, have you ever found yourself struggling to achieve results similar to those individuals who seem to respond better to exercise and achieve greater fitness gains? Don’t be too hard on yourself because the answer often lies in our genes.
The booming field of exercise genetics explores the intricate relationship between our genetic makeup and our response to physical activity. Genetic factors significantly influence how our bodies respond to exercise. For example, some people experience rapid gains in fitness with relatively light training, while others may require more intense regimens to achieve similar results. This is in part due to genetic factors affecting muscle growth, oxygen-carrying capacity, and metabolic efficiency.
Genes and Athletic Performance
One of the most fascinating aspects of exercise genetics is its influence on athletic performance. Genetics can determine whether an individual excels in power-based sports or endurance-based activities. Muscles in the human body consist of different types of muscle fibers which can be broadly categorized into two main types: slow-twitch (conducive to endurance activities like long-distance running and cycling due to their superior oxygen utilization capacity) and fast-twitch (associated with bursts of strength and sprinting prowess). Most individuals are born with a mixture of both slow-twitch and fast-twitch muscle fibers, with genetic factors playing a role in determining the proportion of each fiber type. The exact ratio of slow-twitch to fast-twitch muscle fibers can vary between individuals, and it can also change over time due to factors like exercise and training routines.
For instance, the ACE gene (Angiotensin-Converting Enzyme) insertion/deletion (I/D) polymorphism can affect an individual’s response to endurance exercise where the I allele is associated with improved endurance performance, making individuals with this allele more likely to excel in sports that require sustained aerobic activity. In other cases, the ACTN3 gene (Alpha-Actinin-3), which encodes the alpha-actinin-3 protein is primarily found in the fast-twitch muscle fibers. Individuals with a specific genetic variation (R577X) of this gene may have an absence of alpha-actinin-3 protein in their fast-twitch muscle fibers, resulting in reduced explosive muscle strength and a higher prevalence of endurance-based sports. Mutations in the PPAR-α gene (Peroxisome Proliferator-Activated Receptor Alpha) are associated with an individual’s response to endurance exercise and lipid metabolism where down-regulation or deletion of this gene may increase fatty acid oxidation and, as a result, affect endurance capacity.
Weight Management
Struggling to lose or gain weight despite a diligent exercise regimen and proper nutrition? Genetic factors can be a contributing factor. Diversity in genes related to metabolism, appetite, and fat storage can impact an individual’s ability to manage their weight through exercise and diet. ADRB2 gene (Beta-2 Adrenergic Receptor) is involved in regulating fat metabolism and energy expenditure. Variations in the ADRB2 gene may influence how efficiently the body burns calories. Genetic changes in the FTO gene (Fat Mass and Obesity-Associated) are associated with body weight and fat mass. These variants may impact an individual’s ability to manage their weight through exercise and diet.
Cardiovascular Health
Genetics can also influence an individual’s cardiovascular response to exercise. Some people may have genetic predispositions to lower or higher blood pressure, cholesterol levels, and heart rate responses during exercise. The APOE gene (Apolipoprotein E) is associated with lipid metabolism and cardiovascular health. Certain variants of this gene may influence an individual’s response to exercise in terms of cholesterol levels and cardiovascular outcomes. Recognizing these genetic factors can be crucial when prescribing exercise for cardiovascular health.
Exercise Adherence and Motivation
Do you ever wonder why some people naturally gravitate toward an active lifestyle, while others find it challenging to maintain exercise routines? Genetics also play a role in an individual’s motivation and preference for physical activity. The DRD4 gene (Dopamine D4) encodes a dopamine receptor, where a study linking variability in the DRD4 gene to an individual’s inclination to seek novelty and stimulation. This could, in turn, influence their desire to engage in physical activities or explore new exercise routines. Another gene, BDNF (brain-derived neurotrophic factor), has been linked to the reward system in the brain and may play a role in exercise motivation and the feeling of reward associated with physical activity.
Muscle Recovery
Genetic factors can affect an individual’s muscle recovery after exercise. Certain genetic variations can lead to faster recovery and less post-exercise soreness, while others may require more time and specific recovery strategies. Genetic variations in the COL5A1 gene (Collagen Type V Alpha 1 Chain) have been linked to susceptibility to musculoskeletal injuries in athletes. Certain alleles may increase the risk of conditions like Achilles tendon injuries and ligament sprains.
Conclusion
Exercise and our genes are intricately connected. While genetic predispositions don’t guarantee success in a particular sport, they can provide advantages that when combined with environmental factors, lifestyle choices, and rigorous training, contribute to athletic excellence. Understanding these genetic factors can help tailor exercise programs to individual needs, optimizing the chances of success and reducing the risk of injury. These sources and genetic markers shared here represent just a small portion of the vast body of research in the field of exercise genetics. Ongoing research continues to uncover new genetic markers and their roles in exercise responses, so the field is continually evolving.
~Dr. M
References:
- Bouchard, C. (2012). Overcoming barriers to progress in exercise genomics. Exercise and Sport Sciences Reviews, 40(1): 3-6.
- Bouchard C, Rankinen T, Chagnon YC, Rice T, Pérusse L, Gagnon J, Borecki I, An P, Leon AS, Skinner JS, Wilmore JH, Province M & Rao DC. (2000). Genomic scan for maximal oxygen uptake and its response to training in the HERITAGE Family Study. J Appl Physiol (1985), 88(2):551-559
- Frayling TM, Timpson NJ, Weedon MN, Zeggini E, Freathy RM, Lindgren CM, Perry JR, Elliott KS, Lango H, Rayner NW, Shields B, Harries LW, Barrett JC, Ellard S, Groves CJ, Knight B, Patch AM, Ness AR, Ebrahim S, Lawlor DA, Ring SM, Ben-Shlomo Y, Jarvelin MR, Sovio U, Bennett AJ, Melzer D, Ferrucci L, Loos RJ, Barroso I, Wareham NJ, Karpe F, Owen KR, Cardon LR, Walker M, Hitman GA, Palmer CN, Doney AS, Morris AD, Smith GD, Hattersley AT & McCarthy MI. (2007). A common variant in the FTO gene is associated with body mass index and predisposes to childhood and adult obesity. Science, 316(5826):889-894.
- North KN, Yang N, Wattanasirichaigoon D, Mills M, Easteal S & Beggs AH. (1999). A common nonsense mutation results in alpha-actinin-3 deficiency in the general population. Nature Genetics, 21(4): 353-354.
- Pickering C & Kiely J. (2017). ACTN3: More than Just a Gene for Speed. Front Physiol, 8:1080.
- Pitsiladis Y, Wang G, Wolfarth B & Scott R. (2013). The Genomics of Sport and Exercise. Genomics of Pattern Recognition Receptors: 195-213.
- Posthumus M, September AV, O’Cuinneagain D, van der Merwe W, Schwellnus MP, Collins M & Raleigh SM. (2009). The COL5A1 gene is associated with increased risk of anterior cruciate ligament ruptures in female participants. The American Journal of Sports Medicine, 37(11): 2234-2240.
- Ptácek R, Kuzelová H & Stefano GB. (2011). Dopamine D4 receptor gene DRD4 and its association with psychiatric disorders. Med Sci Monit, 17(9):215-220.
- Rankinen, T, & Bouchard C. (2008). Genes, genetics, and exercise physiology: an overview. In Genetics and sports: 1-7).
- Rankinen T, Pérusse L, Gagnon J, Chagnon YC & Bouchard C. (2000). Genetics of aerobic and anaerobic performances. Exercise and Sport Sciences Reviews, 28(3): 97-104.
- Woods DR, Humphries SE, Montgomery HE & Jones A. (2000). The ACE I/D polymorphism and human physical performance. Trends in Endocrinology & Metabolism, 11(10): 416-420.
All images are from https://all-free-download.com
