I feel like Flex had better conditioning than what he really shows on most pics. Seems like he had an hard time displaying the conditioning in his glutes and hamstrings, off course his lower body from the rear is not as shredded as Ronnie's but if you take a look closely on some of the pics he does has striated glutes and seperated hamstrings.
However most times when he poses, he really displays his back conditioning but doesn't seem to be able to contract his glutes and hamstrings to full potential. Pretty good conditioning from the front, though.
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