How to Pre­pare for Racing at Alti­tude

how to pre­pare to race at alti­tude Ultra X Mex­ico takes place in the beau­ti­ful Cop­per Canyons, home of the legendary Rara­muri people made fam­ous in Chris­toph­er McDougall’s book Born to Run, for our com­pet­it­ors this Novem­ber a ser­i­ous chal­lenge will be...