ON ANY GIVEN WEEKEND IN MARCH, runners fill the roads from Hopkinton to Boston. Some push through 20-plus milers with metronomic speed, following a pace set by their GPS watches. Others struggle through the Newton Hills at a slower clip, refueling with flavored gels and fruity energy chews. Some wear minimalist shoes and clothes that promise performance enhancement. Others throw on a T-shirt, shorts, and faded Red Sox cap. Some cover injured muscles with the stretchable Kinesio tape that so many 2012 Olympians sported. Others prefer the traditional post-run cures of massage and ice.
As the April 15 Boston Marathon nears, the race’s historic course is ground zero for the great experimentation that comes with tackling 26.2 miles. Runners search for anything that will get them to the finish line healthier, happier, and faster: new gear, new technology, new medical studies, new diets, new training philosophies. And that means the months leading up to race day can be filled with trial and error. And all the miles logged in preparation for marathons create giant feedback loops for every runner.