active duty for training
(2) The term “active duty for training” means— (A) full-time duty in the Armed Forces performed by Reserves, or by members of the Space Force in a space force active status (as defined in section 101(e)(1) of title 10 ) but not on sustained duty under section 20105 of title 10 , for training purposes; (B) full-time duty for training purposes performed as a commissioned officer of the Reserve Corps 1 of the Public Health Service; (C) full-time duty as a member, cadet, or midshipman of the Reserve Officers Training Corps while attending field training or practice cruises; and (D) in the case of members of the National Guard or Air National Guard of any State, full-time duty under sections 316 , 502 , 503 , 504 , or 505 of title 32 , United States Code .