Thieme, Trevor. "How Bulgarian Bags Can Help You Get a Killer Workout",Men's Health, March 16, 2020. Accessed March 24, 2023. "Shaped like a crescent moon and inspired by the goat-and-sheep-hefting prowess of shepherds, the Bulgarian bag is essentially a re-engineered sandbag. Instead of containing a single bladder of sand, they're usually filled with individually wrapped sand packets and padded with wool to create a solid, curved (typically goat leather) sack that's more stable than a traditional duffel-shaped sandbag."
