Is having a good memory worth all that work?
One of the big questions in science has been how to get rats to lift weights. The rats simply refuse to do bench presses. Until we could get rats to lift weights, we had no way of comparing aerobic exercise, like walking and running, to anaerobic exercise, like weightlifting.
I suppose we could have used humans, but they are so unreliable. Actually, scientists tried using elderly females in some experiments. (I hasten to make a disclaimer here. In spite of this fact, I will be making no snide remarks concerning gender in this column. My wife is my proofreader.) However, scientists found it much easier to extrapolate rat data to humans than from elderly females, so we were left with the problem of weightlifting for rats.
The process turned out to be surprisingly easy. The scientists simply tied weights to the rats’ tails and put their food at the top of a ladder. This method of using a heavy tail, along with food as incentive, has been a great benefit to me personally. It has enabled me to build powerful muscles that enable me to sit for long periods of time without tiring.
We needed rats to lift weights because we already knew that if rats had access to a running wheel, they produced more cells in the area of the brain controlling memory and performed better on memory tests. We didn’t know if anaerobic exercise such as weightlifting would have the same effect.
Scientists at the University of Columbia began to think that weight training might improve memory when they did the previously mentioned experiment with elderly women experiencing early, mild dementia. The women were assigned to groups with prescribed exercise regimens. Some did mild weight training, others did stretching and toning, and the third group walked.
They determined memory loss by asking the participants to find their car keys and recall their husbands’ names. The stretched and toned group failed miserably. The other two groups only failed in recalling their husband’s names, indicating a clear benefit from both exercises.
Unfortunately, when these ladies were scheduled to come in for postmortem brain analysis, they all forgot.
So once again, we had to turn to rats. It turns out it really didn’t do rats who were trained as runners any good. They still got caught and their brains analyzed. These “runner-rats” had increased levels of BDNF (brain derived neurotrophic factor). This compound apparently supports neurons and helps grow new neural extensions.
Weight trained rats didn’t have more BDNF, but they did have an insulin-like growth protein that also promotes cell division and support. So apparently weight training, or in this case tail training, does have its benefit for memory also.
Unfortunately, it’s not clear which protein is used by elderly females in husband recognition and key finding.
More research is needed (isn’t it always?) before these results can be applied to actual humans. I’m not sure I have a lot of faith in this data, however. My grandpa started walking five miles a day five years ago. But he forgot to come home, and now we don’t know where he is.
Personally, I am not sure that having a better memory is worth the extra work. The longer I live, the more I mess up. There are a lot of things I’d just as soon forget. It seems like not being able to find the car keys would be a small price to pay, in aggravation, for the ability to put certain things out of my mind.
However, we can all rest easier now knowing that one of the big questions in science has been answered: how to get rats to lift weights.
I want to thank Dr. Ed Bonan-Hamada from the Colorado Mesa University Math Department for sending me this information. I’m not exactly sure, though, why he thinks I needed it.
Gary McCallister, mccallis@ coloradomesa.edu, is a professor of biology at Colorado Mesa University.