Statistical evidence (and experience) has shown that running at 95.2% of LTV for 65 min. provides the optimum training effect for improving both LTV and running economy
ya right, do you make this stuff up
Please, don't be such an idiot. These guys have worked with people like Todd Harbour, 3:50 miler, John Lodwick, Pat Porter, and mny other greats, and have spent HOURS crunching numbers using the information available to them based on race times, workout programs, and the athletes completing them. Fitness, for whatever reason, DOES seem to improve in 30 minute increments in a "Stair step" fashion.