I need to confess something: I hate traditional cardio.

The thought of spending an hour on a treadmill or a stationary bike fills me with a unique kind of dread. For years, I thought this was a personal failing. The fitness world told us that hours of cardio were the price of admission for staying healthy, and I just couldn't bring myself to pay it. It was boring, it left me feeling drained, and I never stuck with it.

So, I quit. I just stopped trying to force it.

And it was one of the best decisions I've ever made for my health.

During my deep dive into my own perimenopause symptoms, I discovered the work of Dr. Stacy Sims, a scientist whose entire career is dedicated to female physiology. Her mantra, "Women are not small men," was a lightning bolt. I realized I wasn't lazy; I was just following the wrong rulebook.

Her research showed me that for women in midlife, our declining hormones change everything. We're more prone to losing muscle and bone density, and our bodies are more sensitive to stress. The most effective way to fight this isn't endless cardio; it's building and maintaining lean muscle.

I decided to commit fully to her method. I'm now four months into this new way of training, and I can tell you without exaggeration: I have never felt better. I feel stronger, more energetic, and more powerful in my own skin than I did in my 30s.

My weekly schedule is built around her core principles, and it's more effective and time-efficient than anything I've ever done before. Here’s what it looks like:

1. I Lift Heavy (3 times per week).

This is the non-negotiable foundation. Three days a week, I dedicate about 60 minutes to a full-body strength training session. This includes a proper warm-up, the main lifts, and a cool-down. The goal is to lift heavy enough that the last couple of reps in a set are a real struggle. This is the signal my body needs to build and maintain muscle, which is my single best defense against osteoporosis and metabolic decline. The feeling of competence I get from lifting something heavy has also been a powerful antidote to the feelings of vulnerability that can come with perimenopause.

2. I Do One HIIT Session (1 time per week).

Once a week, I do a High-Intensity Interval Training (HIIT) session. This is different from the all-out sprints. A HIIT session might involve something like 45 seconds of hard effort (e.g., kettlebell swings, battle ropes) followed by 15-20 seconds of rest, repeated for 15-20 minutes. It's a different kind of stimulus that's fantastic for cardiovascular fitness and metabolic health.

3. I Do One SIT Session (1 time per week).

This is my shortest, most intense workout of the week. Sprint Interval Training (SIT) involves a few bursts of absolutely maximum, all-out effort. For example, on a stationary bike, I'll do a 20-30 second sprint as hard as I can possibly go, then recover for 2-3 minutes. I only do 3 or 4 of these reps. The entire workout is over in less than 20 minutes, but the metabolic benefits are huge.

4. I Walk. A Lot. (Every Day).

This is the constant, low-level activity that supports everything else. My non-negotiable goal is to hit around 10,000 steps every single day. I take walking meetings, I pace when I'm on the phone, I take a walk after dinner. This daily movement is crucial for managing my blood sugar, keeping my energy stable, and helping my body recover from the more intense workouts.

That's it. That's the system.

I spend less time doing boring exercise than ever before, but I'm getting exponentially better results. I'm building a body that's resilient and strong enough to handle the demands of my life as a founder.

I'm not punishing myself with exercise I hate anymore. I'm training intelligently for the body I have today, and it has changed everything.

All the best,

Sonja Rincón

Founder & CEO, Menotracker