Here Katja is working glutes, hamstrings, calves, abs as well as her back muscles (isometrically). This exercise must be performed properly or it can be quite dangerous. And please progress slowly with the weights (dumbbells or bar). I mostly see deadlifts done with atrocious form that can injure the back. Yikes! Please message me if you have any questions about weight training form or how to begin any training. I am also available for nutrition coaching.