One of the most exciting areas of exercise research is the investigation of cognitive function. What scientists have learned so far is that brain neurons, the special cells that help you think, move, perform all the bodily functions that keep you alive, and even help your memory, all increase in number after just a few days or weeks of regular activity. In a study in which researchers used an MRI machine to measure the amount of brain tissue in adults 55 years of age and older, they found results, consistent with other studies of aging and brain volume, showing there were substantial declines in brain tissue density as a function of age in areas of the brain responsible for thinking and memory, but importantly, the losses in these areas were substantially reduced as a function of cardiovascular fitness. In other words, the fittest individuals had the most brain tissue.
Walk a straight line: Look for a straight line on the floor (like floor tiles) and try to walk along it. The key here is to land with one foot directly in front of the other and also land on your heel first. Try with arms extended out and then relaxed at your sides. To progress, try walking forward to one end and then backwards to the other. Then try walking forward only with your eyes closed. Walk back and forth 10 times.
For aerobic exercise: Walking, dancing (when's the last time you took a ballroom-dancing class?), biking, and swimming are all good options. You can also try exercise videos. Collage Video is a good resource. They have lots of videos for individuals of all ages (search their site for "seniors"). Also check out your local senior center, rec center, Y, or local fitness center for classes that are appropriate for you. Many centers offer exercise classes for seniors. They're out there if you look.
This one sounds tough, but you don't have to be an engineer or tech wizard to take on the challenge. By following basic guidance and instructions, anyone can build their own computer. It's fun to learn what parts go where and why, and with having the ability to choose specific parts or components, your personally built computer is more than likely to out-perform one you would pick up at the store.