If you’ve been told that cardio has to be intense to be effective, I’ve got good news: sometimes slow and steady truly wins the race — especially when it comes to metabolic health.
Let me introduce you to Zone 2 cardio — a form of low-intensity aerobic training that’s gaining traction in the longevity and functional health space for good reason.
What Is Zone 2 Cardio?
Zone 2 refers to a specific range of exercise intensity that’s low to moderate, where your body primarily uses fat as its main fuel source.
- You’re moving briskly but not breathless.
- You can carry on a conversation, but you’re breathing heavier than normal.
- It typically falls around 60–70% of your maximum heart rate.
➡️ Quick formula:
220 – your age = max heart rate
Zone 2 = 60–70% of that number
For example, if you’re 40 years old:
- Start by estimating your maximum heart rate:
220 – 40 = 180 beats per minute (bpm) - Then calculate 60–70% of that number:
- 60% of 180 = 0.60 × 180 = 108 bpm
- 70% of 180 = 0.70 × 180 = 126 bpm
✅ So your Zone 2 heart rate range is approximately 108 to 126 bpm.
If you don’t have a heart rate monitor, the “talk test” works: If you can talk but not sing, you’re likely in Zone 2.
Why Zone 2 Matters — Especially for Functional Health
Here’s where it gets exciting.
Zone 2 training doesn’t just help with cardio fitness — it can improve how your body produces energy, burns fat, and handles stress. It targets the mitochondria — your cells’ energy factories — and trains your body to become more metabolically flexible.
Science-backed benefits of Zone 2:
- 🧠 Boosts mental clarity and mood
- 🔥 Enhances fat burning
- 💪 Increases mitochondrial density (hello, more energy!)
- ❤️ Supports heart health and circulation
- 🧬 Improves insulin sensitivity
- 🌿 Reduces overall inflammation and chronic disease risk
If you’re working on issues like fatigue, blood sugar regulation, weight loss resistance, or even brain fog, Zone 2 could be a game changer.
How to Train in Zone 2
The goal is to keep your heart rate in that “Zone 2 sweet spot” for 30 to 60 minutes — ideally 3–5 times per week.
Examples of Zone 2 activities:
- Brisk walking (especially uphill)
- Easy jogging
- Steady cycling
- Swimming or rowing
- Elliptical at a light pace
- Hiking
💡 Pro tip: If you’re walking and can talk without gasping but feel your heart rate slightly elevated — you’re probably there.
🛠️ Consider using a fitness tracker or heart rate monitor to dial it in precisely. (We recommend Polar, Garmin, or Apple Watch. Get one on Amazon here)
How It Fits into a Functional Medicine Lifestyle
Unlike high-intensity workouts that can spike cortisol and stress your adrenals, Zone 2 is gentle, sustainable, and restorative — making it ideal for:
- People recovering from chronic illness or burnout
- Those working on adrenal or thyroid health
- Clients with metabolic syndrome, pre-diabetes, or insulin resistance
- Anyone looking to age well and protect long-term vitality
Try This: Your Zone 2 Cardio Challenge
Aim for two 30-minute sessions of Zone 2 cardio this week.
Pick an activity you enjoy — walking, cycling, light jogging — and focus on keeping your pace in that steady, conversational zone. Use a heart rate monitor if you have one, or try the “talk test” to stay within your target range.
It’s simple, low-stress, and highly effective.
