Extensieve Interval Training !full! May 2026

– better to finish a session feeling you could do one more rep than to be gasping for breath. That “easy but not too easy” sweet spot is where the magic happens.

Unlike intensive intervals (which target VO2 max or lactate tolerance at near-maximal efforts), focus on improving aerobic efficiency , capillarization (blood vessel density in muscles), and lactate clearance at a comfortably hard pace. They are a cornerstone of base building for runners, rowers, cyclists, and swimmers. 1. What Is Extensive Interval Training? | Aspect | Extensive Interval | Intensive Interval | | :--- | :--- | :--- | | Primary goal | Aerobic development, fat oxidation, stroke volume | VO2 max, lactate tolerance, speed | | Intensity | 75–82% max HR (or 65–75% of HR reserve) | 90–95% max HR | | Lactate level | ~2–3 mmol/L (below lactate threshold) | 4–8 mmol/L (above lactate threshold) | | Work:rest ratio | ~1:0.5 or 1:1 (short rest) | ~1:2 or 1:3 (long rest) | | Feeling | “Comfortably hard” – can speak short sentences | Hard – cannot speak more than a word | | Typical duration | 1–6 minutes per rep | 30 seconds – 4 minutes per rep |