How Genetics Affect Fitness & Weight Loss

The key to genetic fitness.

It is becoming more evident that some individuals are able to achieve more out of their training than others without having to carry out the same effort or intensity. More surprisingly, some achieve so little out of the effort they put in which indicates that the response to exercise can vary dramatically. The majority will benefit from training in one way or another, however there are a minority who may not experience any effect, whether that be a development in aesthetics or reducing the risk of developing diseases like diabetes, says Professor Claude Bouchard.

The Genes study

Genetic codeHis research group at Louisiana State University in the US have measured the vital role genetic make-up has on people who are more resistant to diseases when they exercise. 742 people from 213 different families were put on a vigorous training program for 20 weeks to improve endurance. Oxygen uptake, blood pressure, heart rate, blood flow and insulin resistance were measured. Some participants showed great improvement, while others showed no improvement at all.
Many variables were considered including the fact that none of the participants had taken part in regular physical activity six months prior to when the experiment was initiated. Overall oxygen uptake increased by an average of 17%, the most trainable subjects however, increased their oxygen uptake by 40%, while the least trainable people experienced no improvement at all. The variations were equally as varied in blood pressure, heart rate and other markers of fitness level. Bouchard reported that the impact of training on insulin sensitivity improved by 58% in the participants who followed an exercise program, but 42% showed no improvement at all. In the volunteers who showed the largest improvement in insulin sensitivity 51 genes were expressed in the muscle, double the level of those who showed the least improvement. Many of these genes were a surprise to the researchers due to the fact that these genes have not previously been linked to exercise. Many people experience the difficulty of regularly participating in exercise but achieving minimal results says Kathryn North of the Institute of Neuromuscular Research at Children's Hospital at Westmead in Sydney, Australia. Furthermore, additional research identified that people with either type-2 diabetes or pre-diabetes who walked or cycled at a moderate intensity 4 to 5 times a week for 12 weeks had lost an average of 4,5 kg in body weight and many had reduced their blood glucose levels. However, it is not that simple for everyone, those with a higher blood glucose level to start with demonstrated that it was harder to control it with exercise, even if excess body weight was lost. Fitness developments were also minimal when cardiovascular competencies were measured during a treadmill test.

With all of this considered, it can be concluded that there are many variables to consider for each individual, highlighting the importance of tailor made programming and support.

References

  • Bouchard C1, Blair SN, Church TS, Earnest CP, Hagberg JM, Häkkinen K, Jenkins NT, Karavirta L, Kraus WE, Leon AS, Rao DC, Sarzynski MA, Skinner JS,Slentz CA, Rankinen T., Adverse metabolic response to regular exercise: is it a rare or common occurrence? PLoS One. 2012;7(5):e37887.
  • Rankinen T, Fuku N, Wolfarth B,Wang G, Sarzynski MA, Alexeev DG, Ahmetov II, Boulay MR, Cieszczyk P, Eynon N,Filipenko ML,Garton FC, Generozov EV, Govorun VM, Houweling PJ, Kawahara T, Kostryukova ES, Kulemin NA, Larin AK, Maciejewska-Karłowska A, Miyachi M, Muniesa CA, Murakami H,Ospanova EA, Padmanabhan S,Pavlenko AV6,Pyankova ON,Santiago C,Sawczuk M,Scott RA,Uyba VV,Yvert T18, Perusse L, Ghosh S, Rauramaa R, North KN, Lucia A , Pitsiladis Y, Bouchard C, No Evidence of a Common DNA Variant Profile Specific to World Class Endurance Athletes, PLoS One. 2016 Jan 29;11(1):e0147330.