Write an article based on this "Go back to school. Take free classes. Use skills you have already gained frequently. Pick up a new hobby. Build things."
Going back to school is a great way to get that brain working again and more education has obvious benefits. You don't even need to get a whole degree. Your employer may be willing to help you finance classes that further your job skills, or you can just take a single class in a subject that interests you. If you just don't have the money or time, there are also a number of free classes available online. Some are even from top universities, like Harvard. Try Coursera, Khan Academy, or even just Ted Talks to get the university experience, without the price. You may even be eligible to take a free course at a local college or university. Some colleges and universities offer free courses for mature learners. With your brain, much like your muscles, it's kind of a "use it or lose it" situation. The longer you go without using information and skills, the rustier they get. Frequently use basic skills, like doing math, in order to keep those skills fresh and ready to use. Try using skills that you have not used in a while, such as woodworking, knitting, sewing, or doing home repairs. Learning a new skill is also a great way to give your brain a workout. Creative skills especially, like music, dance, and visual art, will exercise different parts of your brain and all have incredible benefits. Whether you're building robots or a new bench for your hallway, using your brain to figure out how to make something (especially from scratch with no instructions) is a great workout. Get some basic building skills and then get your brain limber with some practical creativity. Try doing a do-it-yourself project to learn new skills and make something in the process.