> Covering a 4.2-mile (6.8 km) stretch of the Thames in West London, from Putney to Mortlake, it is over three times the distance of an Olympic race.<p>This is unbelievably challenging. The 2km race is infamous:<p>> Physiologists, in fact, have calculated that rowing a two-thousand meter race — the Olympic standard — takes the same physiological toll as playing two basketball games back-to-back. And it exacts that toll in about six minutes. [0]<p>Imagine doing that more than 3 times consecutively without stopping.<p>[0]: <a href="https://archive.nytimes.com/6thfloor.blogs.nytimes.com/2013/07/01/an-oarsman-is-a-verb-meaning-to-row/" rel="nofollow">https://archive.nytimes.com/6thfloor.blogs.nytimes.com/2013/...</a>