What are the best natural substitutes for anabolic steroids? at 47yrs i have low production of testosterone but still train

None: There are no "good" natural substitutes for testosterone - virtually all otc preps are taken orally and increase one's risk of peliosis hepatis/hepatitis/liver cancer, in addition to further suppressing one's native testosterone production. You should be seen by a urologist or endocrinologist. (very common - occurs in 1/4 men in our lifetimes...).