Full body exercise. Slams require a coordinated effort between your upper and lower body to maintain the flow of the exercise. This exercise requires your core muscles including your glutes, abs, low back, spinal erectors, and even your rotator cuffs to work together to power the movement.The movement can help enhance overall athletic performance, improve cardiovascular conditioning, and develop multi-directional core strength.
While more resistance makes each slam more difficult, it will also slow you down, preventing you from producing as much power as you might with less resistance. Identify your strength capacity and adjust the resistance to be able to perform hard slams. Stronger you get the more resistance you can use.