# Zone 4 training Sources: - [[ChatGPT]] ## Summary **Zone 4 training** targets high-intensity aerobic effort near the **lactate threshold**, typically at **80–90% of your maximum heart rate**. It is also known as **threshold training** and is a key zone for boosting performance in endurance sports. Zone 4 training is a powerful tool for improving endurance performance. It teaches your body to work just below its limit, making you more efficient at high speeds and intensities while delaying the onset of fatigue. ## Notes ### 🧠 Key Concepts - **Effort level**: Hard but controlled; speaking is difficult and limited to a few words. - **Heart rate zone**: ~80–90% of HRmax - **Perceived exertion (RPE)**: 7–8 on a 10-point scale - **Fuel usage**: Mostly carbohydrates ### 💡 Benefits - Increases lactate threshold (you can go harder, longer before fatiguing) - Improves aerobic power and speed endurance - Enhances cardiovascular and muscular efficiency at high intensities - Prepares body and mind for race-like efforts ### 🏃 Examples of Zone 4 Workouts - 3 × 10-minute intervals at threshold with equal rest - 20–30 minute continuous tempo efforts near race pace - Sweet spot cycling intervals (just below FTP) ### ⚠️ Notes - Recovery between intervals is essential to maintain quality - Often used in race-specific preparation blocks - Overuse can lead to fatigue—balance with Zone 2 and rest days |Training Zone|Energy Substrate|Muscle Fiber| |---|---|---| |zone 4|CHO|type IIa|