Unlike traditional dumbbells, the kettlebell's center of mass is extended beyond the hand, similar to Indian clubs or ishi sashi.
John Du Cane and Pavel Tsatsouline are also credited with starting the modern kettlebell fitness movement in the USA in 2001 with the manufacture of kettlebells in the US and the creation of the world's first kettlebell instructor certification program.
In May 2008 he completed his certification in Russian Kettlebell Systems (R.K.C) in Copenhagen, Denmark under the tuition of the world famous Russian Instructor Pavel Tsatsouline.