After decades of swearing by workout classes, I switched to weightlifting. I never expected to be so impressed by the results.

• Despite doing frequent workout classes for over 20 years, I felt weak at 37 years old.
• I started weightlifting at my local gym and gained strength surprisingly quickly.
• Eight months into my regimen, I feel better in my body and have a healthier perspective on fitness.

For as long as I can remember, I've been a workout-class enthusiast.

When I was 17, I followed my mom to Jazzercise classes, and at 30, I was in boot-camp classes trying to figure out how anyone "bounces back" after pregnancy.

I was still loyal to group fitness in my late 30s, but at 37, I felt weaker than I'd like to. I wondered: For someone doing so many classes, shouldn't I be — or at least feel — a lot stronger?

I'd been lifting the same 10-pound weights for decades, never progressing to a heavier set. And when one of my five kids asked for a piggyback ride up the stairs, my husband was always the one to oblige (partially due to my pesky back condition).

Eventually, I took a more critical look at my workouts, examining their frequency and the actual movements I was doing. I thought about the strong, fit people I knew my age and realized they lifted weights.

So, I researched the closest gym and chose one purely based on proximity to my house, ready to try something new.

I walked into the gym as a complete beginner

On my first day at the gym, the owner convinced me that I was exactly where I should be, walking me through a slow and steady onboarding program.

I tried not to compare myself to the extremely fit people, who looked like they came straight out of a Navy SEALs brochure, and did my best to ignore the clank of the heavy weights hitting the ground.

The staff logged my baseline abilities as I bench pressed, squatted, and performed other strength-training moves.

Although I had done countless leg lifts, crunches, and planks, I'd rarely done traditional weightlifting. Knowledge came with time.

Soon, I learned about one-rep maxes (the maximum amount of weight a person can lift for a single exercise), bought proper lifting shoes from Puma, and started studying form tips on Instagram after class.

The muscle soreness I felt after each gym session reaffirmed that I was working my body in ways that I hadn't during my group fitness classes.

Although I had plenty of moments when I questioned whether I was in the right place, I told myself that being the least experienced person in the room was a good thing. As I'd learned in the business world, this can be the best place to learn.

Shortly after I started lifting regularly, I felt better in my body

I began taking weightlifting seriously last summer and noticed results fairly quickly.

I didn't lose weight or have a dramatic visual transformation, but my body felt different; I had a structure that supported my frame rather than just a weak core that felt like it went somewhat dormant between pregnancies.

I considered my weight less important than my ability to pick up heavy things without feeling pain. Another benefit I didn't expect? I left the gym each day with a weightlifting high that lasted at least 24 hours.

Lifting weights changed my definition of what it means to be fit

The biggest surprise of joining a weightlifting gym was seeing who I was exercising next to.

Although some of the mega-fit athletes initially intimidated me, I came to understand that my gym was for everyone. I've lifted with retired women over 70, teenagers, moms, and people fighting off medical conditions.

As I watched all of them lift heavier weights than I thought possible, I realized that a fit, strong body comes in many different shapes.

I also learned that weightlifting is about doing big, powerful moves along with exercises that work smaller muscles to fortify my joints.

By following a consistent program and surrounding myself with people who held me accountable, I gradually built strength, going from bench pressing 80 pounds to 115 pounds.

Eight months into my regimen, I no longer feel out of place at the gym. My knees don't hurt and creak on stairs. Most importantly, when my preschooler asks for a piggyback ride up the stairs, I no longer have to say, "Go ask Dad."