Did you know DNA affects your exercise motivation?
Moving, grooving, exercising and genes: The secret behind your love of exercise
Exercise begets exercise, which means that Susie, a seasoned runner, is more likely to continue running than Mike, who has never set foot at the gym. It is a proven fact that people who exercise are more likely to keep it up, because really, the hardest part about exercising is getting started. Motivation is the biggest hurdle to taking up running or going to the gym. Without proper motivation, whether it is the need for a partner in crime or the strength of will to subject ourselves to a gruelling routine, we procrastinate and find excuses to avoid exercise. But for some of us, going for a bike ride or a run almost feels like second nature, because we have inherited an advantage in the form of a genetic variant in the BDNF gene which enhances our motivation to exercise.
The BDNF gene encodes a protein called the brain-derived neurotrophic factor, which controls the function of nerve cells or neurons. Most of the neurons in our brain are made even before we are born. However, some parts of the adult brain can still grow new neurons using a process called neurogenesis. BDNF not only promotes the growth of new nerve cells using neurogenesis, but it also supports the survival of old neurons, which is absolutely necessary for cognitive functions like learning, thinking and memory. These are the same functions affected by neuropsychological disorders, schizophrenia or depression, as well as Alzheimer’s and Parkinson’s, all of which are linked to low BDNF levels.
Now, if you are wondering what learning or Alzheimer’s disease has to do with exercise, the link is BDNF. Interestingly, certain types of exercise can enhance both neurogenesis and cognitive functions, and BDNF levels are at the bottom of what is known as exercise-induced neurogenesis. Exercise boosts your BDNF levels and can beef up your brain, which is actually a blessing to those of us who carry a version of the BDNF gene known as rs6265 that affects how much of the BDNF protein is made. People who carry the altered BDNF gene (rs6265) make a lot less protein compared to people with the normal version of BDNF, which should translate to decreased cognitive advantages as well as increased risk for neuropsychiatric disorders.
However, Mother Nature, in the form of evolutionary adaptation, has provided us a backup plan through “motivation”. People with one altered version of BDNF actually respond more positively to exercise and don’t find exercise as tiring. These individuals are internally driven to exercise more frequently and are also more likely to continue exercising even when offered with the choice to stop. So, basically our brains have adapted to compensate for this inherited BDNF reduction by motivating us to be physically active and boost our BDNF production through exercise.
The relationship between BDNF and exercise however, is a bit like a self-fulfilling prophecy. If you can just start exercising, you are actually genetically programmed to love it and to stay active. Boosting BDNF levels through exercise can have tremendous positive effects on both your physical and mental wellbeing. With this in mind, the question is whether knowing that you are a low BDNF producer would be enough to get you off the couch.