Three-Intensity Training Distribution: How Should LIT / MIT / HIT Be Allocated?

Introduction

Contemporary endurance training science revolves around one core question: What should the time distribution be among LIT (Low), MIT (Moderate), and HIT (High) intensities? This ratio directly determines the direction of adaptation and training efficiency.

Defining the Three Intensities

Using the three-zone lactate threshold model as an example:

Four Mainstream Distribution Models

Common Mistakes Among Amateur Riders

The actual distribution for most amateur riders is:

• LIT: 20–30%
• MIT: 50–60% (the “gray zone” trap)
• HIT: 10–20%

The result is slow progress, susceptibility to overtraining, and persistently low HRV. Seiler calls this distribution “an approach no elite athlete uses.”

Why Do Amateur Riders Get Stuck in MIT?

• Mindset issue: feeling that “low-intensity riding isn’t training”
• Limited time: a 1-hour session easily becomes an all-out effort
• Group ride culture: pace naturally gets pulled up to MIT
• Lack of power control: without a power meter, riders rely only on feel

Research Directions

Seiler & Kjerland (2006) laid the foundation for POL through observations of Norwegian endurance athletes; Esteve-Lanao (2005) analyzed Spanish marathon runners and showed that the group with the highest LIT proportion improved the most; Stöggl and Sperlich’s series of studies compared the effects of different distributions, with POL winning out in most cases.

Practical Recommendations

• Use heart rate rather than feel to judge intensity (investing in a heart rate strap is the best value)
• Keep weekend long rides entirely in LIT; no sprinting to chase wheels
• Do HIIT sessions separately; don’t mix them into the middle of a long ride
• Calculate your weekly time distribution and force yourself to look at the data
• Try polarized training for 8 weeks, then evaluate your progress; most people are surprised by the improvement

Conclusion

Intensity distribution is the most important yet most overlooked concept in training science. Changing your intensity distribution requires no more training time, no more expensive equipment, and no greater talent—only self-discipline and consistency. For amateur riders in Taiwan, this may be the most worthwhile training change to invest in.

Related Reading

• Polarized vs. Pyramidal Training: Physiological Evidence and Applicable Scenarios for Two Intensity Distributions
• Polarized vs. Threshold vs. Pyramidal Training: How to Choose Among Three Intensity Allocation Philosophies?
• Pyramidal Training Model Explained: The Balanced Approach Between Polarized and Threshold
• Polarized vs. Threshold Training: Why 80/20 Repeatedly Wins Among Elites