I would say "Definitely. Yes."
I'm happier when I look in the mirror. I'm happier when I walk out of the gym after my second POUND class. I'm happier knowing I'm doing my best effort to get fit.
I'm especially happy when I end the day knowing that I've spent more calories than I've eaten. My Fitbit makes it harder to deceive myself, because one of the functions is a live update of "Calories Burned". Combine that with the FitDay food log of everything I eat, and know how long it will take to lose a pound. A pound is 3,500 calories. If my calorie deficit is 500 calories a day, it will take seven days to lose a pound.
My Fitbit also tells me how many calories I spend on a specific exercise. Because I wear it, and it measures pulse, it knows if I'm doing an exercise lightly, moderately or really pushing it. It is shocking to me how few calories can be burned giving it my all for half an hour. It makes the calories in any rich food look very expensive indeed. Suddenly a half cup of borscht (hold the sour cream) looks much better than a doughnut.
My mood affects the people with whom I live. When I am happier, I can also see that they are happier too. It is okay to be happy. Unselfish, even. (smile)