Defense Secretary Pete Hegseth announced Wednesday that he is rolling out a new screening program for “testosterone deficiency” among troops, calling it necessary to allow them to operate at their “absolute best.”

The screenings will be conducted annually as part of service members’ required medical screenings for those 30 and older, he said. Troops under 30 can volunteer to be tested. In a video on social media, Hegseth said receiving testosterone replacement therapy would be voluntary.

When asked about what conditions Hegseth was looking to address with the new policy, the Pentagon referred to Hegseth’s remarks in the video that talked about keeping troops “strong, resilient and capable” and that the rigors of the modern battlefield demand “maximum psychological and mental readiness.”

Over the past several years, special operations troops — and specifically Navy SEALs — have come under scrutiny for their use of testosterone and similar substances to enhance performance.

The death of a SEAL recruit during training in 2022 led to a discovery of substances in his possession, including testosterone, and revealed far more rampant drug use among the elite program than was previously acknowledged.

A year after the recruit’s death, the Navy said it would begin a drug-testing program to screen for “any hormonal substance, chemically or pharmacologically related to testosterone, that promotes muscle growth.”

Hegseth said his new initiative is “not about artificial enhancement.”

The Pentagon did not respond to questions about what research or academic studies underpinned the move. It also didn’t say if female troops would be able to be screened for lowering estrogen as they entered perimenopause.