We have previously reported on drugs for Alzheimer's that have failed while in clinical trials. And within the last decade, out of hundreds of clinical trials, only three drugs have made it to the market to treat the symptoms of Alzheimer's, not the disease itself. After decades of research and billions of dollars spent on drug development, the best way scientists know of staving off the progression of Alzheimer's disease is now exercise that stimulates the brain in different ways.

University of Maryland School of Public Health researchers have just published a report in the Journal of Alzheimer's Disease, suggesting that physical exercise in the elderly can stimulate parts of the brain associated with memory and help them to reduce the progression of mild cognitive impairment (MCI), or memory loss. The scientists used functional magnetic resonance imaging (MRI) studies that exercise not only improved memory in those who were already diagnosed with MCI, but also increased their overall brain function.

The Study

Dr. J. Carson Smith. lead author on the study. stated that "after 12 weeks of being on a moderate exercise program, study participants improved their neural efficiency - basically they were using fewer neural resources to perform the same memory task... no study has shown that a drug can do what we showed is possible with exercise."

The study took older adults between the ages of 60 and 88 who were physically inactive and put them on a 12-week exercise program including treadmill walking guided by a personal trainer. Two groups of individuals, those with MCI and those without, showed an increased ability in memory recall and both showed an increase of over 10 percent in cardiovascular fitness.

What Type Of Exercise

The exercise was not too strenuous and included 150 minutes a week (just over 20 minutes a day) that encouraged participants to increase their heart rate and sweating, but was not so strenuous that they could not conduct a conversation while exercising.

To test the participants' recall, researchers studied their brain activation using fMRI scans while asking them to identify famous people from their lives, such as Frank Sinatra. The scientists saw that after exercise, both groups of older people used less brain power to recall the right answers, showing an improvement in cognitive efficiency.

"The task gives us the ability to see what is going on in the brain when there is a correct memory performance," Smith explained. And the brain regions that saw the most improved efficiency are well-known parts of the brain affected by Alzheimer's diseases, including the temporal lobe and the parahippocampal gyrus.

Smith and his group are planning a larger study, which will include more patients and compare healthy individuals to those with a well-known genetic risk factor for the development of Alzheimer's. Patients will also be followed for longer periods to determine if the effect is lasting or if the exercise needs to be maintained.

Source: Smith JC, Nielson K, Antuono P, et al. Semantic Memory Functional MRI and Cognitive Function After Exercise Intervention in Mild Cognitive Impairment. Journal of Alzheimer's Disease. 2013.