The way the body responds to different types of training varies a lot between individuals. Some seem to be almost effortlessly good at endurance training, while others may have more of a talent when it comes to more intense exercises, such as heavy weightlifting. Some recover quickly after a tough training session, while others may need several days to bounce back. A large attributing factor to these differences can be found in the way we take care of ourselves and our bodies, in the sense that we give or don’t give it the right conditions to thrive. However, the other side of the coin is our genetics. Science has identified strong associations between certain genetic variants and for example injury susceptibility and recovery time as well as our ability to perform.
When it comes to susceptibility to injury and recovery time, research has found that three biological areas seem to be highly genetically relevant: connective tissue remodelling, inflammation and oxidative stress. Connective tissue remodelling is a response to stimuli such as exercise and mechanical load, and it can lead to both physical gains and increased susceptibility to injury. With the help of a DNA test that specifically looks at genetic variations within these areas, it is possible to tailor a training program that supports the body instead of predominantly breaking down tissue. When genetic variations that increase the risk for injury are present, it is important to include conditioning and flexibility into the training routine as well as making sure that the nutritional intake is sufficient.
Inflammation is a normal immune response that is an essential part of tissue healing after exercise. However, in some instances, the body secretes higher than normal amounts of pro-inflammatory cytokines, resulting in an increased recovery time to avoid excessive tissue damage. If these genotypes are present, it can be very helpful to incorporate an anti-inflammatory diet as well as a tailored schedule for the amount of recovery needed in between training sessions.
Oxidative stress is a state of imbalance between free radicals and antioxidants in the body. Free radicals are normal but highly reactive by-products of biological processes that generate energy, such as those that occur during training. When the free radical load is too high, it can cause damage to DNA, proteins and cellular membranes. Antioxidants are free radical scavengers that can neutralize the free radicals. Long-term light to moderate regular exercise can increase the antioxidant levels, as well as intake of a variety of colourful fruits and vegetables. Some genetic variants have been associated with higher levels of oxidative stress leading to an increased need of antioxidants.
When considering performance, it has been well established that genetic factors are responsible for a lot of the variance observed. Depending on every individual’s unique ability to respond to different types of training, the ratio of aerobic, strength and weight training will vary. For example, a person’s sporting performance is largely dependent on blood flow and respiration, and some gene variants are associated with either an increased or a decreased oxygen transport to the musculature. In addition, some individuals carry genotypes that increase the aerobic capacity, for example via increased cardiac output (the amount of blood the heart pumps out per minute). Another area which could have a great impact on performance during training is the muscle and bone composition. The base of our structural properties making up these tissues is formed by our genetic makeup. Some specific genotypes related to this can lead to a greater potential within strength, power or speed. Thus, knowledge of which genotypes one carries can be very helpful in tailoring a beneficial training program.