# Zone 3 training
Sources:
- [[ChatGPT]]
## Summary
**Zone 3 training** involves moderate to moderately hard aerobic effort, typically performed at **70–80% of your maximum heart rate**. It's often referred to as the **"tempo zone"** or **aerobic threshold zone**. Zone 3 training targets aerobic endurance and metabolic efficiency. It helps athletes sustain faster paces for longer durations but should be used strategically to avoid overtraining or stagnation.
## Notes
### 🧠 Key Concepts
- **Effort level**: Sustainable but challenging; speaking is limited to short phrases.
- **Heart rate zone**: ~70–80% of HRmax
- **Perceived exertion (RPE)**: 5–6 on a 10-point scale
- **Primary fuel**: Mix of fat and carbohydrates
### 💡 Benefits
- Increases aerobic capacity and endurance
- Improves lactate clearance and buffering
- Enhances cardiovascular efficiency
- Bridges the gap between easy base training and harder threshold work
### 🏃 Examples of Zone 3 Workouts
- Continuous 20–60 minute tempo runs
- Fast endurance bike rides or long intervals
- Sustained efforts at marathon pace (for trained athletes)
### ⚠️ Notes
- Zone 3 is sometimes called the “grey zone” because it's too hard for full recovery but not hard enough to elicit max adaptations—yet it has value when programmed properly.
- Best used in **periodized training** where it's balanced with both Zone 2 and Zone 4 work.
|Training Zone|Energy Substrate|Muscle Fiber|
|---|:---:|:---:|
|[[Zone 3 training]]|fat-CHO|type I-IIa|
Zone 3 training may improve blood flow to the posterior cingulate gyrus and improve executive functioning.[^flow]
[^flow]: [[On cerebral blood flow and exercise]]