Seven healthy men ( 28 + / - 6 yr , mean + / - SD ) performed submaximal intermittent static knee contractions interspersed with maximal voluntary contractions ( MVCs ) every minute to exhaustion ( approximately 50 % of rested MVC force ) in normoxia and hypobaric hypoxia ( separated by 3 d ) after supplementation with Cr ( 20 g.d ( -1 ) for 7 d then 5 g.d ( -1 ) for 4-7 d ) or placebo ( Pla ) in a double-blind , randomized crossover study .
