Doing 21 minutes of “relationship homework” a year could save your marriage. That’s the upshot of a huge new study in the journal Psychological Science. 

Researchers followed couples who’d been married anywhere from a few months, to over 50 years. And every few months, each person rated their levels of satisfaction, love, trust, passion and commitment. 

During the first year of the study, every couple experienced a slight decrease in happiness, and relationship satisfaction. That’s normal, because as our “I love you” hormones gradually wear off, every couple experiences a dip in happiness, and that decline can continue throughout a marriage. But during the second year of the study, the couples who spent 7 minutes every 4 months thinking and writing about their relationship, stayed at the exact same happiness level. 

So, what did the study involve? The couples were asked to think about their arguments from the outside, as if their lives were being judged like a reality show. They were told to consider whether an outsider would think their arguments were worthwhile, or silly, and whether their fights were successful, helped them solve problems, and brought them closer together. 

Because if an argument helps you understand the other person, it’s a successful argument.

Researchers point out that the writing assignment didn’t make the couples fight less often, and it didn’t make the fights less severe. 

But when the couples did fight, they were less upset about it, meaning, their arguments stopped having a negative impact on their relationship, long-term. And that kept their happiness and relationship satisfaction from dipping.