In recent years, the field of sports and performance genetics has grown. We now understand that athletic ability is a combination of genetic predisposition and training, and knowledge of these genetic predispositions plays a vital role in an athlete’s success. 

Athletes are generally defined as being endurance or power-oriented, though some individuals have attributes of both.

Being an endurance athlete refers to having sustained energy and performance over time and longer distances. Examples of endurance athletes include long-distance runners or swimmers, cyclists, and triathletes. 

Conversely, power refers to the ability to exert maximal strength over a short period. Examples of power athletes include weightlifters and sprinters.

While several genes contribute to endurance and power tendencies, two genes play a critical role – the ACE gene and the ACTN3 gene.


ACE Gene

The ACE gene is involved in blood pressure management, fluid balance, and blood sugar levels.   

Having an “I” copy of this gene is associated with endurance athletes and is found in distance runners and other longer-distance athletes. 

Having a “D” copy of this gene is associated with being a power athlete and is found in sprint and strength-oriented athletes. 


ACTN3 Gene

The ACTN3 gene is involved in the development of muscle fibers. Muscle fibers are considered either “fast-twitch” or “slow-twitch,” depending on the speed they constrict and the force they generate. 

Having a “C” copy of this gene is associated with increased muscle mass, strength, and a higher proportion of “fast-twitch” muscle fibers. This version of the gene is found in weightlifting and sprinting athletes. These types of athletes do best with high-load, low-repetition training as well as high-intensity training. 

Having a “T” copy of this gene is less associated with being a power athlete, thus having fewer “fast-twitch” muscles. Those with a “T” copy may do better with low-load, high-repetition exercises during weight training.


Understanding Your Genetic Characteristics

Having an understanding of your genetic predisposition can bring awareness to the types of sports and training that you will respond to best. Whether you are an elite athlete or a weekend warrior, genetic testing plays an important role in improving your performance. In 2022 ADx Health will be releasing myGenoFit, a DNA test for athletes. Click here to learn more.