In 2014, I was working as a trainer in a skilled nursing facility and an assisted living facility. They were attached via a long, dark, secured hallway. I led group strength training 3 days a week there. To this day, it is the most rewarding job I’ve ever had. In many ways, it’s still the job I have. Now I coach people much younger than 102 (the oldest person I have coached), but the key principle, if you can move it, you can improve it, remains the same.

As you can imagine, the physical abilities of my clients in the skilled nursing facility were variable, to say the least. Some clients had lost function in all but one limb; others couldn’t speak, but could move all four limbs despite being in a wheelchair.

One ambitious gentleman in his late 90s was more or less glued to his wheelchair for the first few months of strength training. He was determined to change that. One morning, I walked in to start our session, and he stood right up out of his wheelchair and shook my hand. This is real physiological change happening in the oldest of human tissues.

Another man of similar age had lost function in three out of four limbs. His left arm was fired up and ready to go each morning. We trained the heck out of his left arm. On our first day together, he hardly had the physical or mental energy to do any of our exercises. Before I left that job, I had to come up with increasingly creative ways to give this man more of a challenge. He even restored a little bit of function in his left leg.

I’ve got dozens of these stories from my days at the nursing home, but I think you get the idea.

Now here is the really important message in all of this, and it’s not just that these people got stronger and more capable. It’s more than that. Most of my readers (and current clients) are not bound to a wheelchair in a nursing home, but what I’ve noticed after coaching people from every decade in life is that we keep accepting and rationalizing our expectations for what we can and can’t do at every stage in life. I notice it starting in our 30s. People talk about what they used to do in their 20s but not anymore because they are older. Then, when we are 40, we talk about what we used to do in our 30s but stopped because, well, we are 40 now. The cycle continues until we do less and less and then we die.

The final thing I want to leave you with is this. The goal of having the leg strength to stand up from your wheelchair is just an extreme example, but it’s in the same family of wanting to be capable of managing your own life at 80, or not falling in your 70s, or even playing organized hockey again in your 50s. Our world doesn’t have to get smaller as we age. Older human tissues will adapt to the training that we subject them to.