Exercise is good for you

At the annual Alzheimer’s Association International Conference in July 2015, scientists report some encouraging news about the benefits of exercise. In the first studies to look at physical activity among people already diagnosed with the early stages of Alzheimer’s, researchers reported that:

• People who participated in the exercise program had far fewer neuropsychiatric symptoms (such as anxiety, irritability, and depression). Those in the control group had deteriorated on measures of psychiatric symptoms, while the intervention group improved slightly. This lead to a statistically significant difference between the two groups.
• People in a subgroup of the exercise group who attended more than 80% of the classes and exercised vigorously (raising their heart rate to more than 70% of their maximal rate) had statistically significant (p=0.03) improvements on mental speed and attention, as measured by the SDMT.
• In addition, people who participated in the exercise program improved in physical fitness, physical function, dual-task performance and exercise self-efficacy.

Participants in the study were randomly assigned to either supervised aerobic training or a stretching group for 45-60 minutes four times per week for six months, using community facilities. The aerobic group exercised at 70-80% of their maximum heart rate, while the stretching group exercised at below 35 percent. The researchers tested participant’s cognitive skills (verbal recall, tests of executive function) and examined blood and cerebrospinal fluid (CSF) samples at the beginning and end of the study. Forty participants also received MRI brain scans. Participants completed their assigned exercise activities 92 percent of the time.

The researchers found that:

• Participants who completed aerobic exercise (most commonly using a treadmill) saw a statistically significant (p<0.05) reduction in tau levels in CSF. The effect was most pronounced in adults over the age of 70.
• Aerobic exercise significantly (p<0.05) increased blood flow in the memory and processing centers of participant’s brains, with a corresponding improvement in attention, planning, and organizing abilities referred to as “executive function” (p<0.05).

“These findings are important because they strongly suggest a potent lifestyle intervention such as aerobic exercise can impact Alzheimer’s-related changes in the brain,” Baker said. “No currently approved medication can rival these effects.”