Sergeant Steel ran into trouble here because it contains Shilajit — a type of plant-based resin. Shilajit is banned in Canada because the Canadian government found heavy metal levels when investigating the ingredient. Shilajit is hard to find, and sensitive to water and variations in temperature, so most manufacturers mix it with additives to make it more stable. Research at Boston University School of Medicine found that “nearly 21 percent of 193 ayurvedic herbal supplements [...] contained lead, mercury or arsenic,” and included shilajit on the list of contaminated ingredients. Even though Sergeant Steel lists its shilajit is “purified,” it doesn’t offer any third-party testing to confirm whether or not their shilajit contains heavy metals, and so we cut it.
Researchers at Ball State University found that “strength training can induce growth hormone and testosterone release.” (6) Another study from the University of Nebraska Medical Center researched the acute effects of weight lifting on serum testosterone levels. (7) The results concluded that even moderate weight lifting and light weightlifting increased serum testosterone levels in participants.