While we know that exercise has many physical and mental health benefits, a new study in the Journal of Social and Personal Relationships shows that exercising with a partner might better increase your happiness. Researchers studied 95 undergraduates who were in a romantic relationship and who exercised two to three times a week. They found that compared to exercising without a romantic partner, whether it was alone, with friends, or with strangers, exercising together with a romantic partner led to a greater positive mood during exercise. They had a higher positive mood throughout the rest of the day. And they experienced greater relationship satisfaction. For those of you who struggle with motivation to exercise, consider trying to work out with your significant other.