This is pretty impressive given that these guys are not cyclists.
Shearer was a big soccer star, but he took this on after a month's
training and doing a max of 50 miles in a day.
Wow, max of 50 miles and then jump into 170 miles/day. However, soccer players are typically well-conditioned athletes with strong legs, which is a lot different than a couch potato brushing the chip crumbs off his potbelly and getting on a bike.
Shearer has been retired for a while, and even in his prime he wasn't exactly a midfield workhorse type.