When my grandson JJ celebrated his Bar Mitzvah last spring, I asked him what he wanted as a gift from Grandma. His answer: “I want to take a trip with you!” I was thrilled. I love to travel , of course, and I was utterly grateful that this energetic and amazing 13-year-old boy wanted to spend a week with me. It was a wonderful gift for us both. And boy, did we have an incredible time! However, there is one thing I would have changed if I could: my level of health and fitness .Always the planner, JJ had cleared the idea with his parents long before making his request (I may be Grandma, but Mom and Dad still make the rules!). He had imagined us in Mexico, but after some research and a wonderful travel agent, we settled on Costa Rica . I had never been there, but it has a reputation for being great for families, chock full of activities, and reasonably priced. For my grandson, Costa Rica sounded exotic and exciting. JJ and I were Central America-bound!As soon as we arrived, I knew we’d made a great choice. The resorts cater to American tourists, so communication is easy. There were lots of families and people of every age, and I loved watching these multiple generations enjoying their time together. The whole atmosphere was relaxed and comfortable, and it felt like the perfect tropical getaway but without the premium price tag. (Aside from the thermal waters in Arenal , complete with a swim-up lounge and a sushi bar which, I can attest, is crazy expensive when you are accompanied by your teenage grandson who happens to have a passion for sushi!) Our trip included a perfect balance of higher-end resorts and activities that took us away from the tourist area and into the surrounding country.Related: Tax Planning Should Be at the Top of Your Agenda, Even During the Dog Days of Summer The further we ventured into the country, the more we learned about the people who live there. I loved talking to our driver, who told us where his family vacations (a wonderful rented cabin very near the expensive hotels) and shared that, thanks to the tourism industry, most families earn about $25K/year—a living wage in Costa Rica . With the help of local drivers, we did everything JJ had hoped for. We hurled down a mountain together on zip lines. We explored the Costa Rica n jungle from river rafts. We snorkeled from a catamaran. We trekked over mountain terrain on ATVs. Whenever there was an hour or two to spare, JJ had a new plan—none of which included letting Grandma lounge in a hammock or read a book! Though I was able to get through the trip thanks to sheer willpower, I know it would have been a lot easier and enjoyable for me if I were in better shape. My sedentary lifestyle has taken its toll, which means I needed more time and more help to climb in and out of the jeep, climb to the top of the zip line, and even just walk wherever we wanted to go.On the flight home, I couldn’t help but think back on how challenging it had been for me to keep up. Yes, JJ is 13 and has boundless energy, but there is no excuse for my physical state. When I stumbled across this list of 30 ThingsYou’ll Regret When You’re Old , number 7 hit home: Failing to make fitness a priority.I don’t consider myself “old”—at least not quite yet!—but I’m done with regret! It’s time to take health and fitness seriously. It’s time to make a change. I talk constantly to clients about ways to build better, happier lives as they age. In my blog , I’ve written that living a joyous life is as much about having financial freedom as it is about being mentally and physically healthy so you can enjoy every minute. It’s time I practice what I preach.My late Uncle Joe was everyone’s favorite uncle—whether they were related to him or not. Years ago, he told me that the secret to meaningful relationships is sharing one-on-one experiences with others. Children. Adults. People you love, and people you wanted to like better. It’s some of the best advice I’ve ever received. However, Uncle Joe had gotten something else right too: a lifelong Manhattanite, his daily walks kept him fit and healthy as he aged.Related: How to Protect Your Financial Future by Handing Over the Keys to Your Kingdom My younger granddaughters Noa and Zoe are 11 and 9 respectively. A new goal of mine is to take similar trips with them when they celebrate their Bat Mitzvahs. However, this time, I plan to be fit enough to run circles around them. I've begun working with Nancy S—my new personal trainer. (If RBG can do it, so can I.) I’m changing how I eat and how I live. My body is going to be with me for the rest of my life. I’ve finally decided to give it the attention it deserves. So get ready to try to catch me, Noa and Zoe, because your new and improved Grandma is on her way!