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Smiling Makes You a More Efficient Runner | Outside Online

During the runs, the volunteers were instructed to smile, frown, relax their hands and upper body (by imagining, for example, that they were carrying potato chips between their thumb and forefingers without breaking them), or just think their usual thoughts. The results more or less supported the benefits of smiling. Running economy was a little more than 2 percent better when smiling—an improvement that’s comparable to what you see in studies of weeks or months of plyometrics or heavy weight training.

Concrete goals are easier to achieve/measure = happinesss

Further experiments revealed that when people framed their happiness goals more concretely, they tended to get what they expected. In contrast, abstract goals tended to make people unrealistic. After all, can you really make someone happy in the long-term by telling them a funny story or giving them a gift? Of course not. But you can still make them smile. This research suggests that by thinking in concrete ways about our goals for happiness, we can minimise the gap between our expectations and what is actually possible.