People often blame their negligence of important matters on old age. According to long-term research carried out by David Jacobs at the University of Minnesota in Minneapolis, however, cardio fitness activities can reduce forgetfulness that follows middle age, or the period ranging from ages 43 to 55.

The treadmill test, used by David Jacobs, is widely employed to evaluate physical fitness over time. Source: http://commons.wikimedia.org/wiki/File:RIAN_archive_555848_Testing_on_treadmill.jpg

For the study, Jacobs tested 2,747 people with an average age of 25. He performed a treadmill test on the participants for the first year of the experiment and carried out the same test 20 years later. Cognitive tests, which measured the verbal memory, psychomotor speed, and executive function, were performed 25 years after the start of the study.

In the treadmill test, participants ran or walked on a treadmill that was set to certain speeds and inclinations until they started showing physical symptoms such as shortness of breath. While the participants lasted 10 minutes on average in the first test, the number decreased by an average of 2.9 minutes in the test performed 20 years later.

For every additional minute the participants ran or walked on the treadmill in the first experiment, they recalled 0.12 more words correctly on the memory test 25 years later. In addition, they replaced 0.92 more meaningless symbols with numbers on the psychomotor speed test, which measures the relationship between thinking and physical executions, in the cognitive tests carried out 25 years later. Furthermore, participants with smaller decreases in time on the second treadmill test were more likely to perform better on executive function tests compared to those who had larger decreases. Even after accounting health issues such as high cholesterol and diabetes, the results are significant in that they clearly show maintenance in cognitive abilities in middle age.

David Jacobs claims that these cognitive tests are among the best predictors for determining the development of dementia. For example, one study showed that every additional word recalled on the memory test was associated with an 18 percent decrease in the risk of developing dementia ten years later. Jacobs hopes that these studies will motivate people to continue cardio exercises and help other scientists find ways to treat patients who may be vulnerable to dementia.

References:

1. N. Zhu, D. R. Jacobs, P. J. Schreiner, K. Yaffe, N. Bryan, L. J. Launer, R. A. Whitmer, S. Sidney, E. Demerath, W. Thomas, C. Bouchard, K. He, J. Reis, B. Sternfeld. Cardiorespiratory fitness and cognitive function in middle age: The CARDIA Study. Neurology, 2014.