Cardio Zones 101

Why They Matter & How They Changed My Fitness Journey

 
 

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If you’ve been following my fitness journey, you know I used to go all out in every workout, thinking if I wasn’t completely drenched in sweat, out of breath, and barely able to walk out of the gym… it didn’t count.

Spoiler alert: That’s not sustainable. 😅

About a year into consistently showing up for my workouts, I realized something huge: exercise needs to support my lifestyle, not drain it. As a mom, I can’t afford to completely wipe myself out in the morning and then still expect to have energy for school drop-offs, work, dinner, and all the “mom life” in between.

That’s when I started learning about cardio zones and it has been life changing.

Instead of treating cardio like a one-speed, max-effort situation, I learned that different heart rate “zones” serve different purposes for your body. From building endurance and burning fat efficiently, to increasing power and speed. When you understand how these zones work, you can train smarter, not harder, and actually get better results with more energy left over for your life.

The 5 Cardio Zones

Zone 1: Recovery / Very Light

🫶 Gentle movement like walking or slow cycling.

💡 Helps you recover between harder workouts, supports circulation, and builds an aerobic base without taxing your body.

Zone 2: Endurance / Fat-Burning

🚶‍♀️ You can talk in full sentences here.

💡 Where your body uses fat as its primary fuel source. Incredible for steady energy, building aerobic capacity, and supporting hormone health.

Zone 3: Moderate / Aerobic

🗨️ You can still talk, but you’re starting to breathe heavier.

💡 Improves cardiovascular fitness and stamina. Great for longer runs, rowing, or steady cycling.

Zone 4: Hard / Anaerobic

🗣️ Short phrases only!

💡 Builds speed, power, and lactic threshold. Think sprints or hill repeats. This is intense, so you can’t sustain it for long.


Zone 5: Maximum Effort

😮 Talking? Not happening.

💡 All-out bursts for performance, the hardest you can go for a very short time. Used sparingly for max output training.

Why I Train in Zones Now

Training in different zones has helped me avoid burnout, recover better, and actually see more progress without feeling like I need a nap every afternoon. 

I can push hard when I need to, but I also respect the power of slower, intentional cardio for long-term health, energy, and results.

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