When I think of a curmudgeon, I think of Clint Eastwood in the movie “Gran Torino” or Walther Matthau in “Grumpy Old Men.” They exemplify the bad-tempered, surly stereotype that is often assigned to aging men and women who have allowed their opinionated negativity and rigid mindset to rule who they are.

The truth is that we all have a curmudgeon inside of us. Yet, what I’ve come to understand is that it all comes down to what parts of our mindset we nurture within ourselves that matters.

Here are some tips to avoid becoming inflexible:

>> Stay active physically. You are going to be grumpy if you are not well. What you do in your 40s, you pay for in your 60s so create a routine that’s sustainable and enjoyable. For some, it’s wearing a step tracker or taking the stairwell and parking in a faraway stall for those extra steps. For others, it’s exercising at a gym, taking yoga a few times a week or going meatless on Mondays. Whatever it is, small steps matter.

>> Keep learning new things. A flexible mind belongs to those who believe they are lifelong learners. Learning something new brings pride, joy and wonder to life. When was the last time, you learned something new?

>> Do something for others. Look for people, causes or interests that inspire. You can support the homeless at the Institute for Human Services, walk a dog at the Humane Society or help out with the grandkids. If you live in your head and alone in your house all day and every day, an inflexible mindset is bound to take hold, and the fear of change will only deepen.

>> Examine your relationships. The more advanced you are in life, the more likely it is that you’ve had deep disappointments when it comes to relationships. It’s never too early or late to make peace in your relationships.

>> Life would be perfect if all our relationships grew with us. However, this is not always the case. If you have relationships in which you are feeling tired and frustrated, it’s likely because the patterns were established when different things mattered to you.

Living up to others’ expectation that you should keep doing what you have always done is exhausting. Don’t resist renegotiating your relationships. It’s important to meet people where they are — meaning creating a connection where both enjoy benefits based on who they are now.

For example, if you’ve always expected your adult children to visit you, consider if their lifestyle and schedule would accommodate a visit from you to their home occasionally.

Alice Inoue is the founder of Happiness U. Visit yourhappinessu.com.