# Intensity **High-intensity training** challenges the upper end of your cardiovascular and metabolic capacity. It improves VO₂ max, increases energy efficiency, enhances glucose regulation, and builds both strength and endurance in less time than moderate-intensity work. ## What Counts as High-Intensity Work - Interval training such as **Norwegian 4×4**, VO₂ max intervals, Tabata protocol, or Zone 5 efforts - Short, hard bursts on the bike (e.g., Keiser Zone 5 intervals) - Any workout performed near maximal aerobic capacity with adequate recovery ## Recommended Dosage - **1–2 sessions per week** - Keep intervals high quality with full or partial recovery - Avoid stacking sessions too close together to prevent fatigue buildup ## How to Measure Progress - **[[Wingate 30-Second Test]]:** Peak anaerobic power and fatigue profile - **Lactate Threshold:** Indicates sustainable high-intensity performance - See: [[My lactate threshold]] - **[[Functional Threshold Power]] (FTP):** Practical field marker of aerobic/anaerobic balance - See: [[My Functional Threshold Power]]