Wednesday, September 14, 2016

Is your Fitness Level a Result of your Genes?

Everywhere you go you've probably heard someone say "nothing works for me, no matter what I do I can't get in shape." With recent studies there has been a possible answer to these people's frustration! The fact that no matter what some people do they never seem more fit than when they started exercise can be explained by not the lack of effort, but from your DNA! The genetics of fitness study was published in The Journal of Applied Physiology.
The expectation is you exercise and get fit. However, not always the case!

This study is the first study type that looks at the effect of any type of exercise. The part of the DNA that was looked at are called single-nucleotide polymorphisms (SNPs). It was studied how a certain SNP affects how susceptible a person is to exercise. In this study more than 300,000 people participated in a 5 month long exercise period. They were required to bike stationary three times a week. The intensities that they were to bike at were determined by the scientists and everyone had the same intensity level. After the five month period certain people were much more fit compared to when they had started while others were not. To determine whether fitness had improved they compared the amount of oxygen their bodies needed. This is called a person's VO2 max. For those who were more fit after the five months there VO2 max increased, for others the number barely moved. There seemed to be no definite conclusions to why these people's VO2 max didn't increase, such as because of their age or body mass. However, there was a difference in the genomes. Out of all the participants who completed the exercise period scientists identified 21 specific SNPs that varied between those who got more fit and those who didn't. Since humans get two sets of alleles one from their mother's side and one from their father's there are actually 42 different variations of these SNPs.

What exactly do these SNPs mean? Those who had 19 or more SNPs improved there fitness by more than 3 times compared to those who only had 9 or less SNPs. One of the SNPs located on the ACSL1 gene was shown to have a high effect on exercise. It resulted in as much as 6 percent in the difference between those whose fitness improved and those whose fitness didn't. This makes sense because this gene is known for playing a role in how the body metabolizes fat. Although there still has to be many more studies done on this concept it is interesting to discover that genes may effect physical ability. Within the future more studies will be done with different ethnicity's to determine SNPs that are shared and what other genes may be affected.


  1. This is interesting because it shows that there is a genetic factor behind a predisposition for exercise. While mental desire is a great motivation for fitness, some people just have the physical ability to metabolize more fat and be more physically fit than others.

  2. This is really interesting knowing that some people cannot get more fit than when they started exercising. Humans should closely observe their body’s response to exercise. If an individual has been working out for months and does not see an improvement, then they should attempt a different workout routine. It makes a lot of sense that an individual’s DNA is the reason that no matter what they do they never seem to be more fit than when they started exercising. I am glad to have read that genes may effect an individual’s physical ability.