Your reaction time may be a key indicator of your overall health. Research shows that reaction speed not only reflects brain function but can also predict the risk of early death, heart disease, strokes, and other health problems. As we age, our reaction time naturally declines, which is partly responsible for the decline in athletic performance after the age of 30. However, maintaining a steady reaction speed can signal good brain health and may even help prevent serious health issues later in life.
Understanding the Link Between Reaction Time and Health
Reaction time, or how quickly the body responds to stimuli, is more than just a measure of reflexes. It’s closely linked to how well your brain and body are functioning. Experts have found that slowing reaction times over the years can indicate more than just age—it’s a reflection of the health of various body systems, including the heart, muscles, and brain.
Simon Cox, a cognitive aging expert at the University of Edinburgh, explains that while some people are naturally faster than others, slowing reaction speed over time typically indicates biological wear and tear. This simple metric offers insight into the combined condition of the body’s systems, from neurological function to cardiovascular health.
Testing Your Reaction Time at Home
You don’t need a lab to measure your reaction time. One easy way to test it is the “ruler drop test,” which can be done with a friend and a basic ruler. Here’s how it works:
- Sit at a table with your arm resting on the surface, letting your hand hang over the edge.
- Have your partner hold a ruler vertically above your hand, aligning the zero mark with your thumb.
- Without warning, your partner drops the ruler, and you try to catch it as quickly as possible.
The distance the ruler falls before you catch it reflects your reaction time. A top score is when you catch it before it drops more than 7.5 cm. Results between 7.5 cm and 15.9 cm are above average, while 15.9 cm to 20.4 cm is considered average. Anything beyond that may indicate below-average or poor reaction time.
The Health Risks of Slower Reactions
Studies show that slower reaction times are linked to a higher risk of various health problems, including early death, heart disease, strokes, and respiratory issues. In addition, slower reflexes may also increase the risk of falls, dementia, and loss of independence.
However, experts emphasize that one isolated test doesn’t provide the full picture. Cox points out that individual factors such as gender, genes, lifestyle, and even personality play a role in how fast someone reacts. What’s more important is tracking how your reaction time changes over time. A significant decline can signal a potential underlying health issue, whereas a steady pace suggests good health.
How Reaction Time Declines with Age
Reaction time naturally declines with age. However, experts note that the causes of this decline vary between individuals. The brain may detect stimuli faster than the body can react, as muscles and nerves weaken over time.
Professor Alaa Ahmed from the University of Colorado Boulder explains that in older adults, slower reaction times often result from weakened muscle fibers and less efficient mitochondria, the energy-providing structures in cells. As these physical components deteriorate, it becomes harder to move quickly.
Despite these changes, healthy older individuals can still maintain good reaction times. Research by Professor Matthew Pain at Loughborough University found that older adults could react quickly when triggered by loud noises, although they may not be able to sprint at Olympic speeds. This suggests that while aging affects reaction time, the nervous system can still function well with proper health maintenance.
Other Tests to Gauge Your Reaction Time
Beyond the ruler drop test, there are online tests like the Human Benchmark Reaction Time Test that involve clicking quickly when a box changes color. Large drops in performance on such tests can signal sensory issues or slower decision-making, which are often linked to cognitive decline. A recent study found that slower pattern recognition and weaker vision in older adults could be early indicators of dementia, potentially showing up up to a decade before clinical symptoms appear.
Reaction Time and Brain Aging
Cox explains that one of the reasons reaction time slows with age is the decline in the brain’s white matter, which is responsible for transmitting signals. As white matter deteriorates, the communication between the brain and muscles becomes slower, leading to delayed reactions.
Additionally, nerve pathways linking the brain to muscles weaken over time, which further contributes to slower responses. This slowing of communication between the brain and body is part of the natural aging process, but the extent can vary depending on an individual’s overall health and lifestyle.
Improving and Maintaining Reaction Time
The good news is that you can train to improve your reaction time. Experts recommend “dual-task” exercises, which involve both physical movement and mental concentration. For example, walking while turning your head, balancing on one foot while saying the alphabet, or juggling a ball while naming words are all activities that can improve reaction speed. Participating in fitness classes or engaging in social activities that require focus and coordination can also be beneficial.
Drills that challenge both the body and brain, such as playing sports, learning a musical instrument, or engaging in intellectually stimulating activities like board games, can help maintain and improve reaction time well into older age.
Cox emphasizes that staying socially and mentally active also helps slow brain aging, as it keeps multiple cognitive pathways sharp. This comprehensive approach to maintaining health can help prevent the decline in reaction time, contributing to better overall well-being as you age.
Your reaction time provides more than just a reflection of your reflexes—it offers a glimpse into your overall health. Slowing reaction times can be a signal of underlying health issues, but with regular testing and a focus on physical and mental fitness, you can improve and maintain your reaction speed throughout your life. In the end, your reaction time could be a critical tool in not only predicting but preventing serious health problems.
