In 1979 she conducted an experiment in which she asked a group of elderly men to re-live, well, actually to live, as if it were still in the 1950s. They spoke about all things 50s in the present tense, imagining that they still inhabited those halcyon days of their own youth. No one cooked for them, lifted heavy luggage for them, clutched their elbows as they went up and down stairs. They were asked to take care of themselves, live for themselves, all the while imagining that they were young.
The results were astonishing. One man, by the end of the trial, abandoned his walking cane. Blood pressures dropped. Participants were judged by witnesses to look and appear younger than before. Langer even adds that such youthful thought staves of dementia.
I believe it. Never having purposefully conducted this experiment on my own, I can say that I have proven it to be true over and over again without being aware: never do I feel older than when for some crackpot reason I am actually telling myself I am old. And never do I feel younger than when I am cruising around town on my bicycle from yoga to shopping to the post office to work.
I invite you to read the article, and check out the video, whippersnapper.