Most humans who are into any type of physical training, know very little, if anything at all, about club training. This surprisingly includes sports coaches and certified personal trainers. Their answers usually fall between 'it works your grip' to 'it's good to hit a tire' as an informed dismissal.
The real answer is Rotational Power. Running, throwing, punching, driving all require rotational anatomical movement. The blanket answer is over-all body strength and conditioning. Large muscle groups are recruited to throw, balance, and receive Almost ALL club movements engage the whole body by challenging endurance, coordination, balance, and spatial awareness. Imagine doing yard work, that's right, yard work with a 20lb shovel or axe. Human athletic/working movement from an exercise tool that is moved throughout joint's full range of motion allowing for traction and muscular contraction in one movement. Spinal movement becomes freer. Bending down becomes easier. Reaching overhead, easier. Strength is returned. Life gets easier with more opportunities when you can move properly.
Clubs will make you move better, less pain and stiffness, and build useful muscle while burning gobs of fat. Regular fixed weight clubs are good to start with. Adex Clubs are the choice for more serious strength seekers being that the weight adjusts. Having a full set of clubs OR an Adex Adjustable Club (in 1.25lb choices/19 weight settings in 1) is great to do and accommodate any user for any exercise with the perfect weight.