One Pood weighed 16.38kg, and they increased in increments of 8kg, where 1.5 poods came to 24kg, and 2 poods became 32kg etc.
Because of their incidental and unique design, it soon became apparent that kettlebells could also be adapted for physical activity and fitness in general.
It is very likely that their use as a fitness tool, came about through traders competing against each other. As to who could lift the most or for the longest during their free time.