Exercise is good for your brain. Duh. But until recently the majority of research on exercise and brain health has been done with aerobic exercise. Now, some researchers strapped some weights to the butts of some rats, had them climbed ladders, and investigated the benefit to brain health – specifically to see if it enhanced their ability to overcome induced dementia.
The Big Takeaway? It might be time to rethink the term “gym rat” to describe people who spend so much time in the gym they don’t know much about anything else.
STUDY SETUP: This study used a 100-centimeter-long ladder (a little over three feet) and bags of weighted pellets gently taped to the rats’ rear ends. The animals received a treat when they reached the top of the ladder and soon started climbing it willingly, even without rewards.
INDUCED DEMENTIA: Next, they injected a separate group of rats with a substance known to induce inflammation in the brain, creating a rodent form of mild cognitive impairment or early dementia. Half of these rats then began a weekly program of progressive weight training over several weeks.
TURN ME LOOSE: Next, all the animals, including an untouched control group, were turned loose into a brightly lit maze with a single, darkened chamber. Rodents prefer dark places and during repeated visits to the maze, the animals would be expected to learn the location and aim for that chamber.
WHAT HAPPENED: In the first few iterations, the control animals were fastest and most accurate, and the rodents with mild cognitive impairments faltered. With a little practice, though, the weight-trained animals, despite their induced cognitive impairments, caught up to and in some cases surpassed the speed and accuracy of the controls.
The weight training had “effectively restored” their ability to think.
Microscopic examination of brain tissue showed that the memory centers of the brains in the weight training rats was teeming with enzymes and genetic markers that are known to help kick-start the creation and survival of new neurons, while also increasing plasticity (the brain’s ability to change.)
In effect, the brains of the weight-trained rats were remaking themselves to resemble those of brains that had not been inflamed and impaired.
Now comes the disclaimer part. This study was with rats, not humans, and the who knows how much different methods of weight training may affect the outcomes, and the results need to be replicated approximately 5 bajillion times before blah, blah, blah.
I’m not waiting around for the brain benefits of resistance training to be unequivocally proven.
Taylor J. Kelty, et al. Journal of Applied Physiology 2019 127:1, 254-263