The same is true for social fitness.

It’s not easy to take care of our relationships today, and in fact, we tend to think that once we establish friendships and intimate relationships, they will take care of themselves. But like muscles, neglected relationships atrophy. Our social life is a living system. And it needs exercise. You don’t have to examine scientific findings to recognize that relationships affect you physically. All you have to do is notice the invigoration you feel when you believe someone has really understood you during a good conversation, or notice the tension and distress after an argument, or the lack of sleep during a period of romantic strife.

Focus first on what’s working well. This is the easiest place to begin. Take a look at the relationships on the energizing side of your social universe and consider how you might solidify or encourage what’s great about them. Tell (and show!) those people how much you appreciate them, and why. It never hurts to double down on what’s already bringing energy and vitality into your life. These relationships are already rolling, but there are usually one or two that have slowed down and need a little push to get up and running at full tilt again. Even good relationships tend to repeat the same routines over and over. It might be time to try some new things with them.

If we accept the wisdom—and more recently the scientific evidence—that our relationships really are among our most valuable tools for sustaining health and happiness, then choosing to invest time and energy in them becomes vitally important. And an investment in our social fitness isn’t only an investment in our lives as they are now. It is an investment that will affect everything about how we live in the future.

These findings, along with our findings about the importance of empathic effort (discussed in Chapter 5), point to an important idea about intimate relationships: if a couple can cultivate a bedrock of affection and empathy (meaning curiosity and the willingness to listen), their bond will be more stable and enduring.

Advances in communication technologies are making remote work much more common for jobs in business, media, education, and other industries, and an always-on mentality threatens to make workers’ home lives into an extension of the work sphere. To say the least, a consideration of how these changes have affected our social fitness has not been a top priority. And yet the state of our relationships is among the most important factors in our health and well-being.