Brooks Laich believes couples need to "continually evolve" to avoid feeling "indifference" to one another.
The 36-year-old hockey player - who is married to professional dancer Julianne Hough - believes it is vital to put "energy" into a relationship in order to accept the changes and "challenges" that come with long-term love.
Speaking on his iHeartRadio podcast, 'How Men Think', he said: "You're going to change, I'm going to change in the course of my life, my wife is going to change in the course of her life.
"But also, I think people over time can develop some sort of indifference where once there was an attraction.
"They can just develop an indifference, and it's not staying connected enough to continue to learn and grow and accept your changes, accept their changes, and also challenge each other.
"There are so many resources out there -- seminars, books, all kinds of things.
"There's areas in your relationship you can undoubtedly grow, and maybe there's just an indifference in people where they don't want to put in the energy to do it, or they don't think they can."
And Brooks doesn't believe many couples communicate as well as they should and if they only had the "courage" to open up about their "desires and cravings", their relationships would be much more strong and stable.
He said: "I don't think a lot of people in their marriage really, really truthfully communicate all the needs and desires and cravings and yearnings they have for themselves, for their partner, all of it.
"I think they lack a little bit of courage there, to share those things, that could really actually keep people together and light their marriage on fire."