At http://www.crossfit.com/discus/messages/21/3943.html they said that lactate threshold training releases growth hormone and quoted your book. Here's the quote in particular:
Could you please explaain some of the science? Thank you SO MUCH in advance!!!A great benefit of the repetition method is an increase not only in all strength but also in endurance. This method is also commonly known as lactic acid tolerance training. It promotes a high degree of growth hormone production, which can aid in size and strength. To validate some of the findings at Westside, in Science of Sports Training by Thomas Kurz, high reps with very light weight are stated as being beneficial in the rep range 100-200.