Looking akin to the handbag of a Hollywood celebrity or a cannonball with a handle stuck on top, the little kettlebell is probably the earliest piece of weight training equipment apart from the rocks and logs used by early cave people of course.

Kettlebells have their origins in Russia or Scotland (depending on who you want to believe) and while they were popular ‘historical’ training tools this popularity waned with the invention of dumbbells, barbells and weight machines. Over the past decade, however, kettlebells and a particular type of ‘kettlebell training’ have been undergoing a revival, as personal trainers, and equipment producers and retailers’ embrace ‘functional’ training with free weights as opposed to machine based training.

Are Kettlebells a ‘functional’ training tool?

What is it about kettlebells that make them familiar with the advocates of technical training? Why would you, as a personal trainer use a kettlebell as opposed to an ordinary dumbbell or weight machine with your clients?

By having the handle on top of the weight, the center of mass of the Kettlebell is extended beyond the hand when it is held. This makes it much easier to complete the explosive, multi joint, swinging type movements that characterize kettlebell training and other forms of ‘functional’ training for that matter.

Now we have a series of articles discussing ‘functional’ training at ptdirect.com so we’re not going to go over this ambiguous term in detail here, suffice to say that what actually makes training ‘functional’ for a client is that it is ‘fit for the clients purpose’, namely that the training will achieve the individual clients goals in the most efficient and enjoyable way for them.

So regardless of the structural advantages, kettlebells have for particular types of training, they will only be a ‘functional’ tool for clients that want to benefit from this kind of training and can perform this type of training safely and more efficiently.

What is ‘Kettlebell Training?’

Now kettlebells can be used just like dumbbells to add weight to conventional exercises such as squats, deadlifts, lunges and bent over rows. In fact, any standard weight training exercise that you’d use a dumbbell for could be performed with a kettlebell.

‘Kettlebell training’ however is entirely different to only performing conventional exercises with kettlebells as opposed to dumbbells. Kettlebell training is a particular form of training that:

1. Is focused on explosive, power great oriented swinging movements. These movements utilize more fast twitch muscle fibers, and these fibers have a greater capacity for developing size, and strength.

2. Includes the Olympic lifts – the clean, the clean and jerk, and the snatch. These vast, multi joint exercises use every muscle in the body and as before-mentioned can be great for burning lots of calories and stimulating lots of muscle in a short period

Is Kettlebell Training Safe for your Training Clients?

Conclusively any resistance training has the potential to be dangerous, just like crossing the road has the potential to be dangerous. As a personal trainer, you minimize the inherent dangers for your clients by only selecting exercises that suit their capabilities, and you instruct your clients on how to perform those exercises safely. That being said, as kettlebell training exercises are compound, multi-joint, power oriented exercises, kettlebell training does carry more ‘risk’ than many other forms of resistance training when not executed properly.

To understand why there is a greater risk of injury with kettlebell training we need to have a brief review of biomechanics and the human energy systems…

Basic Biomechanics Recap

The base of support is simply wherever the body touches the ground – so in any standing position, the base of support includes the feet and the area between the feet. The center of mass is simply the middle of an object where there is the same amount of mass above as there is below, and the same amount of weight in front of, as there is behind, the center point. The line of force is simply the direction that a load acts in. As this skeleton is not holding a charge the line of force reflects gravity which always pushes straight down.

As soon as a person’s center of mass moves outside their base of support, their ability to balance is significantly impaired. If their center of mass moves forward of their base of support, they’ll likely fall forward, and if it moves behind their base of support, they’ll fall backward.

This is why ‘good’ biomechanics for exercises like squats, rely on having the weight placed directly over the client’s base of support, and ensuring that during the movement the client’s center of mass remains directly above their base of support. If the weight were positioned high on the clients’ neck in this image of the squat the customers center of mass would move to the front of their base of support making them vulnerable to tipping forward (as well as having far too much load on a vulnerable part of the spine!)

One of the guiding principles for safe resistance training with standing exercises is to keep the center of mass directly over the base of support. This becomes even more important as the loads that are being lifted get heavier and are performed explosively.

Kettlebells do offer a significant advantage for some of the lifts used in kettlebell training, namely the high pull, and the Olympic lifts – the snatch, the clean and the clean and jerk. The advantage is that the kettlebell can be lowered between the legs thus keeping the center of mass well positioned directly above the base of support. The disadvantage of using bars is that they have to be pulled from the ground up and over the protruding knees which do bring the center of mass slightly forward, thus requiring a very sound, well-refined technique to keep the client balanced and ensure their safety during the lift.

As loads get heavier and, exercises are performed more explosively the risk of injury increases, so it is imperative that the body is well balanced and the structures of the body that are more vulnerable to injury are not exposed to undue risk.
This is where the safety of some of the swinging kettlebell training exercises becomes questionable.

You also need to consider that ‘what goes up must come down.’ With kettlebell swings, the client is usually instructed to ‘pull’ the kettlebell back down into their body from the top position. Combined with the effects of gravity this results in a lot of momentum being created as the kettlebell returns to the starting position. The client will need to be able to resist this energy at the bottom point of the exercise to avoid an injury and loss of balance.

So when we consider the mechanics of kettlebell training like complex, explosive multi-joint exercises, it should be reasonably obvious that there is a high injury risk for clients with minimal resistance training experience. If you’re considering using kettlebell training with any of your customers then adhere to the following guidelines:

Focus initially on instructing clients how to squat. Only move into kettlebell training exercises once customers can squat safely and efficiently, as the squat movement is used in quite a few kettlebell training exercises

Focus on building strength and endurance in your client’s’ core musculature and in particular their ability to hold an abdominal ‘brace.’ The abdominal brace locks the lumbar spine safely in neutral and protects it from injury during any movement.