80/20 Running: Run Stronger and Race Faster by Training Slower

by Matt Fitzgerald

There is a popular belief that Kenyan runners do much more training at moderate and high intensities than do elite runners from other places, but the hard data does not support this myth. In 2003, top French exercise scientist Veronique Billat collected training data from twenty elite male and female Kenyan runners. A subsequent analysis of the data conducted by Stephen Seiler revealed that these runners did 85 percent of their running below the lactate threshold. Since the lactate threshold is slightly higher than the ventilatory threshold, these runners probably did very close to 80 percent of their training below the latter.