Getting slower with age? Here’s why

Do I really want to know why we get slower with age? I love science, particularly the science of health, but I hesitated before looking into possible answers to this question. I’m not completely sure why. I think it’s for fear of acknowledging there are things I simply cannot do anymore. I’ll be 60 next year, and facing up to what that may entail definitely scares me.

Still, one of my aims in later life is to be better at facing my fears. So – why do we get slower with age? According to new research, it may be that it takes us ‘oldies’ more energy to reach our old speeds.

The research compared younger adults – aged 18 to 35 – with older adults – aged 66 to 87. Each participant was asked to use a robotic arm to reach for a target on a screen. The exercise was apparently not unlike moving a mouse around on a computer. 

The researchers analysed the movements involved in reaching the target, comparing the overall trend differences between the two groups. And they did indeed find differences. Older adults modified their movements at certain times. This helped conserve their more limited amounts of energy, compared to younger adults.

Energy conversion, it seems, could be a key to why we get slower with age.

Why do we need more energy to perform the same task?

There’s no definitive answer to that question yet. However, Professor Alaa A. Ahmed, PhD, a lead author of the study, published in the Journal of Neuroscience, has one idea. “With age, our muscle cells may become less efficient in transforming energy into muscle force and ultimately movement,” he said.

“We also become less efficient in our movement strategies, possibly to compensate for lower strength. So we recruit more muscles, which costs more energy, to perform the same tasks.” 

The study did not merely look at why we get slower with age. It also incorporated a second element into the study, that of ‘reward circuitry’. It’s well known that our brains, as with many other animals (think of Pavlov’s dog), respond positively to rewards. But does this also fade with age? Prof. Ahmed and his team set out to find out.

Again using the robotic arm exercise, the researchers added a reward element. If the participants hit the onscreen target using the arm, they were ‘rewarded’ with a ‘bing’ sound effect. 

In both age groups, the prospect of hearing the ‘bing’ improved the speed at which participants reached the target. But the results of that exercise provided an interesting twist – the groups achieved their improved speeds in different ways.

Those in the younger group simply move their arms faster. But the older adults saved time through quicker reaction times. 

The practical benefits of knowing why we get slower with age

This is all very interesting, but can we use this knowledge to achieve a useful end? Quite possibly. The greater our understanding of the reasons we get slower with age, the better our chances of delaying its occurrence.

Further to that, Prof Ahmed believes this research could lead to better diagnostic tools. While we do get slower with age, a loss of speed can also be a symptom of other conditions. The development of new diagnostic tools for movement-related disorders as a result of this research would be a boon. 

As with most ground-breaking studies, further research will be needed to verify these findings. But the knowledge revealed in this study alone could prove beneficial, even to ageing individuals like me. Thanks to this research, I now know that while I may not be able to do much about my loss of energy efficiency, I can still improve my reaction times.

It turns out the answer to my original question is ‘yes’. I’m glad I know why we get slower with age, because I know there’s something I can do about it.

Have you noticed that you are getting slower with age? In what ways has that affected you? Let us know via the comments section below.

Also read: Short-term exercise can lead to long-term heart improvements

Disclaimer: This article contains general information about health issues and is not advice. For health advice, consult your medical practitioner.