Watching fit seniors can give you hope for when you reach the golden years. It doesn't have to mean health problems and frailty. Have you ever thought of competing in a masters games in your area? The International Masters Games Association is a world-class-level event where older people can compete in their favourite sports.
If you're not at the world-class level, there are smaller events in countries around the world where you can compete at the local or regional level. If you're at the age where you could compete now, maybe you could give it a try. Do some training and show up. Many of these events have very few people attending, so they would be happy to have to have you compete, no matter how good you are.
If you're not at the age where could enter any of these events, it could become a longer-term goal of yours to compete when you are of age. Getting older doesn't have to mean sitting around all day. The athletes below might give you some encouragement.
Dr. Jeffry Life was an older doctor who was over weight and unhealthy. He decided to change his life around and get into shape. The change from before to after was dramatic. He has some books out on how to do what he does, one of them being "The Life Plan".
The first fit senior I'd like you to meet is Jack LaLanne. Born in 1914 in California, Jack LaLanne was sometimes called the "Godfather of Fitness". His television show inspired many to get in shape. He opened one of America's first fitness gyms. He encouraged women to get in shape. He started out his life unhealthy and a "sugarholic", but he soon became the opposite.
By the time of his death in 2011, he had worked out well into his senior years. He performed feats of strength in his later years that people in their 20s would have problems with. Try reading his book published in 2009. One of the tricks I gleaned from it was to eat more fruit, if you're trying to eat less junk food.
The next fit senior I'd like you to meet is Olga Kotelko. A Canadian born in 1919, she held numerous world records in track and field by the time - and she did that in her 90s. Try reading the book on her by Bruce Grierson. It goes in depth into her life and might give you some hope for yourself. In track and field you fall a lot, during jumping and whatnot. This might be beneficial for you. Getting used to falling in your senior years might prevent you from breaking a hip, according to the "use it or lose it" maxim.
Earl Fee, a Canadian born in 1929, has set many world records in track and field. Try to find some videos of him sprinting in his 80s on the Internet. He looks like someone much younger than him. It is quite inspiring to see him run with long, powerful strides, not the shorter strides of other people his age.