I've written several posts in the past which connected physical exercise to brain fitness. Well I just came across another article which further highlighted this connection.
The article reported the results of a study performed by Dr. Patricia A. Boyle and her colleagues of Rush Alzheimer's Disease Center in Chicago. They found that the greater a person's muscle strength, the lower their likelihood of being diagnosed with Alzheimer's. The same was true for the loss of mental function that often precedes full-blown Alzheimer's.
The researchers initially measured the strength of nine muscle groups in the arms and legs of 970 dementia-free men and women 54 to 100 years old (their average age was around 80). During a four year follow-up, 138 people in the study developed Alzheimer's. These individuals were older and had worse mental function than the rest of the study participants. They also were weaker. They found that muscle strength had a strong influence on the risk of the disease. People who ranked in the top 10 percent for muscle strength were 61 percent less likely to develop Alzheimer's than the weakest 10 percent. Stronger people also showed a slower decline in their mental abilities over time.