No such thing as functional strength as a general defination.
What is functional for one sport is not necessarily functional for another
Bodybuilding isn't a sport.
By functional strength I specifically mean the ability to do work in real life... not just the gym.
They're also a very effective method of fat loss (with muscle sparing) for those who hate cardio.
If there's one legitimate criticism of kettlebells it would be their simplicity. There are really only a few basic, great exercises and people who get bored have to increase the weight/intensity or start doing more creative exercises and end up injured.
Kettlebells will never provide the variety some people need. That being said I'd still argue most guys/girls that hit the gym with any regularity either ignore or do the three foundational exercises wrong anyways.
