House Oversight and Government Reform Committee Chairman Darrell Issa and ranking member Elijah Cummings called for action by the players union and hinted they may call individual players before the committee.
"We are disappointed with the NFLPA's remarkable recalcitrance, which has prevented meaningful progress on this issue," the congressmen said in a letter to the NFLPA Executive Director DeMaurice Smith.
"We intend to take a more active role to determine whether the position you have taken - that HGH is not a serious concern and that the test for HGH is unreliable - is consistent with the beliefs of rank and file NFL players."
There was no immediate response by the NFLPA.
HGH testing was agreed to as part of the 2011 collective bargaining agreement between the NFL and union but has not been implemented because of concern over the test by the players association.
The congressmen said the two sides had assured them 15 months ago they would work to begin testing for HGH as soon as possible.
"Despite being the first of the major professional sports leagues to agree to test for HGH, the NFL has now fallen far behind its counterparts in implementing the agreement," their letter added.
"While NFLPA management may not believe that HGH is a problem in the NFL, the words of your athletes suggest otherwise. We hope the facts collected by the committee will provide you and the NFL with the information necessary to resolve this matter."
Major League Baseball earlier this month became the first North American major professional sports league to implement in-season testing for HGH in its players.
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