“I don’t want to be old when I’m old.” That sentiment was shared in a recent article in The New York Times by Elaine LaLanne, the 97-year-old widow of Jack LaLanne, who was one of the first TV celebrities to introduce personal fitness to millions of Americans.

So, what does it mean to be “old”? For many people, old is anyone 10 to 20 years older than their current age. The trouble is, it’s inevitable that you’ll age into the definitions of old that you considered to be true earlier in your life.

At age 70, I’ve blown through several definitions of old that I held earlier in my life. However, now I realize that I’m approaching the lifespan ceiling and can no longer put off ignoring the fact that some day, I will be old—at least chronologically.  So, I’m looking carefully at how not to be “old” when I’m old.

Refine our personal fitness habits

As you might expect, Ms. LaLanne provides a good role model when it comes to personal fitness. She exercises every day for at least 20 minutes, doing jackknifes in her bed and incline pushups at the sink, walking on a treadmill, and building upper-body strength in the gym. She also practices good nutrition and maintains a healthy weight.

The importance of exercise, nutrition, and healthy weight to your fitness in retirement is well known. As you age, however, you’ll need to refine your exercise and nutrition habits.

For example, for many years, I exercised by swimming, biking, and practicing yoga. However, Ms. LaLanne’s focus on building her upper-body strength made me reflect on the fact that my parents became quite frail in their 80s and 90s; building upper-body strength could have helped them be more independent in their later years. So now, I’m regularly visiting the gym and lifting weights.

Eating more protein is another example of a refinement recommended by nutritionists for people in their 70s and older.

Expand our definition of “not being old”

Another frequent catch phrase you often hear is that “Age is an attitude.” Usually that means you should think like a young person. But what does that mean to a person who’s in their retirement years? For me, it means being curious, continuing to learn, and trying new things, no matter how old I am. However, I’ll also want to be discerning about these choices by applying my lifetime of experience: I don’t need to try things simply because they’re “shiny and new,” but I’ll be open to seeing if the new thing will really make my life better.

For example, I recently joined an outrigger canoe club, which has provided me with a new way to keep fit, build my upper body strength, and make new friends. I’m also investigating the idea of using Apple Pay, a mobile payment service that can replace a debit or credit card with built-in safety features. After rejecting it for years as some newfangled thing that only young people use, I think it’s time to look into it.

Another common definition of “old” is people who are no longer independent and need to rely on others for their daily care needs. What I’ve found, however, is that many people in their 80s and 90s commonly rely on others for social and logistical support. In reality, they’re “interdependent,” accepting help for various needs but also providing support to family, friends, and their community at large.

As a result, I’m looking for ways I can accept relying on others without compromising my sense of independence. One clear example is being ready to accept rides on public transportation or from family, friends, and Uber as my willingness and ability to drive diminishes in my later years.

Nurture our social fitness

Viewing retirement as a permanent vacation, when all you do is play, travel, and pursue hobbies, simply doesn’t work for retirements that can last 20 to 30 years. We need to be helpful and relevant to our communities, family, and friends no matter how old we are. That can mean continuing to work in some way, volunteering, or simply being there for family and friends when they need help. In our later years, our social fitness is just as important as our personal fitness.

Here’s an idea to consider: Ask close family and friends what age they think is old, and how not to be “old” when you’re old. You’ll start an insightful and provocative conversation!

Ms. LaLanne ended her interview with one more powerful insight: “You have to move. If you don’t move, you become immovable.”

Great inspiration and advice for not being old when we’re old!