From Box Life Magazine:
The physical benefits of weightlifting are well documented. Improved speed, power, muscle mass, weight loss, etc.—most CrossFitters have already seen the positive impact that consistent weightlifting can have on the body.
But what about the brain?
Recent studies suggest that regular resistance training (i.e. strength training and weightlifting) can provide a host of benefits to our mental health—such as improving an individual’s memory, slowing the onset of dementia, and providing a boost to our overall cognitive performance.
In the 1990s, scientists at the Salk Institute for Biological Studies in La Jolla, Calif., first discovered that exercise provides benefits to the brain. The scientists examined the impact on brain activity in mice by having one group ‘exercise’ on running wheels, while another group remained sedentary. The results showed that the mice that exercised produced far more cells in the area of the brain controlling memory creation than animals that didn’t run, as well as performing better on subsequent memory tests.
While the exact link between weightlifting and the performance of our brains is still being examined, we do have a basic understanding as to how resistance work can serve to provide an added boost to our mental capacity.
When we exercise, our body releases molecules that tell us to grow more muscle, tendon, ligament and bone cells, and make the ones we have even more efficient and powerful. Essentially, our body adapts to the different stresses we put it under so that we are better prepared the next time that same stress comes up, which is another reason why CrossFit is based on a constantly varied programming methodology—to keep our body constantly guessing, thus constantly developing. These molecules also affect your brain cells and blood vessels, encouraging more growth, power, and efficiency.
Some of these molecules include IGF-1 (insulin-like growth factor 1), a protein that promotes the survival of existing cells and encourages the growth of new ones. It is believed that the brain must have a good amount of IGF-1 in order to promote angiogenesis (a physiological process through which new blood vessels are formed from pre-existing vessels) and neurogenesis (responsible for populating the growing brain with neurons). Another hormone that is released is called BDNF (brain-derived neurotrophic factor). BDNF helps to promote the survival of neurons in the brain and encourage the growth and differentiation of new neurons and synapses (a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another cell). The hormone is found in the highest quantities in the part of the brain that is linked with learning and processing new material, as well as in the cerebral cortex—the part of the brain that allows you to store memories and execute higher thinking.
Furthermore, Teresa Liu-Ambrose, a principal investigator at the Brain Research Center at the University of British Columbia, has speculated in an article in the New York Times thatresistance training strengthens the heart—thus improving blood flow to the brain and improving cognitive function. She adds that because you actively have tothink about proper form and learning the technique when weightlifting, there can be an upsurge in brain usage.
So is there any proof to back up these claims?
Actually, there is—though the studies that examine the relationship between resistance training and cognitive function are primarily conducted on older individuals. A 2013 study conducted by the University of British Columbia examined the impact of resistance training in areas of on conflict resolution, attention and memory in women aged between 70-80 that were suffering from mild cognitive impairment (MCI). MCI is a condition where people have memory problems—though they are not severe enough to interfere with daily life. However, it is often considered to be the very early stage of Alzheimer’s Disease. In the study, 86 women were randomly assigned to three groups:
26 participants did resistance training, such as lifting weights, to build muscle strength.
24 walked outdoors in an aerobics program.
27 took basic balance and toning classes as a control.
In advance of the trial, all of the women performed baseline memory tests.
The exercise classes were held twice weekly over the course of six months.
After six months, the women in the toning group scored worse on the memory tests than they had at the start of the study. Their cognitive impairment had grown. But the women who had exercised, either by walking or weight training, performed better on almost all of the cognitive tests after six months than they had before.
The researchers claimed that their results showed that resistance training can improve both your cognitive performance and your brain function. What is so unique about these findings is that they show that strength training can benefit our executive function and associative memory—two process that are highly sensitive to the effects of aging and neurodegeneration (and ones that are usually damaged in the early stages of Alzheimer’s disease).
If only six month of resistance work was able to positively affect the cognitive condition of these women, imagine what impact years of weightlifting could have on our brains? More research needs to be conducted into how weightlifting can help our brains perform, but if it helps us retain our memories and be more alert, well, that’s as good a reason as any to keep pumping the iron.