Genetics
Heritability of Traits
“The heritability of athletic status (regardless of sport) is estimated to be 66%. Height, which is critical for success in some sports, is highly heritable, with about 80% of the variation due to genetic factors. Body type (having mesomorphic or ectomorphic somatotype) is also highly heritable.” (Guth and Roth). The types of traits will be talked about later in this Jeopardy game, but the genes that we inherit from each of our parents plays a large role in how we are able to perform as an athlete.
Testosterone
Testosterone is able to increase the production of hemoglobin and red blood cells in the human body. When blood testosterone is elevated, it can give an athlete an advantage in athletic events where muscle strength, speed, and endurance is essential. This is why “Blood doping” is banned in the NCAA, because it stimulates the production of hemoglobin and red blood cells, which increases the amount of oxygen To the muscles. This is why there is controversy surrounding weather transgender women should able to participate in women’s sports, and why women with high testosterone, due to a condition called DSD, have a “competitive advantage” in athletic events (UW Medicine).
Limbs
A person that is born with longer legs may be a better and more powerful sprinter compared to an athlete that is born with shorter legs because they are able to cover more ground in a shorter amount of time. However, that athlete that is born with the shorter legs may be more agile than an athlete with long limbs because they have a lower center or gravity, which increases stability. Some one with a large wingspan also has an advantage in certain sports, such as basketball, because they are able to reach things that the other players would not be able to without jumping.
Strength
Muscle strength can refer to the amounf of external force your muscles can move. Strength training involves your nervous system to use as many muscle fibers as needed to overcome an external force (Meacham). Having high muscular strength can allow an athlete to generate more force quickly and efficiently. Having strong muscles, “…allows an athlete to perform powerful movements, resist fatigue, and sustain higher levels of physical activity for longer periods”(Peak Performance).
Injury
Genetics can play a large part in the probability that someone will have an injury when in sport. This can be seen in athletes that experience ACL tears. According to Hasani and other contributing authors, “Those with a family history had a 2.5 times greater odds for sustaining a primary ACL injury“. I can personally attribute to this as well. I have torn both of my ACL’s along with my menisci when I was a sophmore and junior in high school. Also, my brother has recently torn his ACL and meniscus as a sophmore in college. We are both athletes. Both of my parents also tore their ACL’s, they have been athletes their whole lives.
Estrogen
According to Anderson, “Each muscle, tendon, and ligament in the body has a receptor for estrogen, and during the menstrual cycle, the structure and function of these tissues change”. Althouh not researched in its entirety, there is a theory that estrogen increases in the body during a persons mentrual cycle, and can cause instability in tendons. This could be a cause of lots of injuries, most notably being ACL injuries. This could be a reason as to why females, “suffer anywhere from 2-9 times higher rates of ACL injuries than males” (Injury Prevention Research Center).
Bone Density and Structure
The density and structure of an individuals bones can impact their performance by limiting their ability to withstand forces of their sport. Those with higher bone densiy tend to have better resilience against injury, especially in high impact activities. And optimal bone structure, such as having appropriate bone geometry and quality, can enhance power generation and efficient movement. Athletes that participate in weight baring sports usually have about a 10% higher bone mass density than non-athletes, which makes them stronger than non-athletes. Being an athlete overall helps to improve your bone density, which can help in the long run in prevention of osteoporosis in the future, which is weak and brittle bones (Gooslby).
Hypertrophy
Muscle hypertrophy is an increase in muscle mass through training in higher sets with more weight. For example, someone who is wanting to achieve larger, visible muscles should perform sets with 6 to 12 repetitions at 75% to 85% of their one rep max (Maecham). Athletes that build their muscle hyper trophy can generate force, improve overall body composition by reducing body fat and increasing muscle mass, and can also help an athlete recover from an injury faster and also repent injury in the first place (TRAK).
Genetic Variants
“As of 2009, more than 200 genetic variants had been associated with physical performance with more than 20 variants being associated with elite athlete status.” (Guth and Roth). Two of the genetic variations that have been found to enhance an athlete's performance are ACE I/D and ACTN3 R577X. ACE I/D has been associated with the endurance of an athlete. This polymorphism gene codes for a certain enzyme that is a part of the reninangiotensin system that is responsible for controlling blood pressure and regulating body fluid levels (Guth and Roth). ACTN3 R577X is associated with power-related performance. This polymorphism codes for a protein only found in fast type II muscle fibers that are used in explosive activities. This allows for athletes that have this genetic variation to have faster explosive movements compared to those that do not have this variation.
Estradoil
Estradiol is a form of estrogen which can enhance endurance for an athlete through improving their carbohydrate usage during exercise, which has the ability to delay fatigue. Estradiol can also optimize muscle metabolism by providing more efficient energy during exercise (DeRosa).
Somatotypes
In humans, there are three main somatotypes, or body types, that can affect an athletes performance. There are mesomorphic bodies, ectomorphic bodies, and endomorphic bodies. Mesomorphic somatotypes are people that have a high muscle to fat ratio that can give them a muscular chest, shoulders, and limbs. Their weight distribution around the body is usually even and they have the ability to gain muscle and weight easily (Bell). Ectomorphic bodies are lean and slender with long limbs, narrow shoulders, and a low muscle mass. People with this type of body may have a fast metabolism and have trouble gaining muscle and losing weight it easily (Bell). Endmorphic bodesare rounder and have a higher body fat percentage with the tendency to gain weight. People with this body type may have wide hips and waist, large bones, and short limbs(Bell). Athletic performance is very dependent on health and skill related components of physical fitness. If an athlete is born with a leaner or more muscle toned body, they may have a better athletic performance as compared to someone who is born with a predisposition to being over or underweight.
Muscle Fiber Types
There are 3 types of muscle fibers that are found in muscles: slow-twitch, fast-twitch, and fast glycolysis fibers. Slow-twitch can function for long periods of time without fatiguing which makes them very helpful in non-powerful and fast movements. Fast- twitch fibers are primarily used in movements that require more energy than just slow-fiber instances, but less energy than explosive movements. And fast glycolic fibers are used for those explosive moments where your body needs rapid and forceful contractions in order to make powerful movements. However, thees fibers fatigue quickly, so this only allows them to be used for short periods of time. According to Physiopedia, the number of slow and fast twitch fibers that are contained in the body greatly vary between individuals and is mostly determined by a person’s genetics.“People who do well at endurance sports tend to have a higher number of slow-twitch fibers, whereas people who are better at sprint events tend to have higher numbers of fast-twitch muscle fibers” (Physiopedia). However, it is possible to improve the power of both of these fiber types through sprinting and endurance training. (Physiopedia).