Some people will only do machine training. Others may only use bodyweight exercises in their programming. Some people will tell you to only use free weights. Others believe that everything should be done using a Bosu Ball. And the latest thing people are starting to make use of more often is the kettlebell. I say, “Use them all”. Increasing your athletic performance or transforming your physique has nothing to do with what tool or apparatus you’re using. It has more to do with how you’re using that tool or apparatus. If I’m using the tool analogy, I wouldn’t use a screwdriver to drive in a nail, would I? Yeah I can, but it’s not to effective. There are going to be certain exercises or situations, where one tool is more appropriate than the other. For instance, kettlebells are my preferred tools for performing a single arm or double armed swing. Or if I’m trying to improve my maximal strength, why work on a stability ball where I going to be limited by how much weight I can use because I’m working so hard to stabilize the damn ball. Think about the movement pattern and what you’re trying to establish with each exercise then select the proper tool. Use all the tools in your toolbox.