When it comes to the trunk we need to look at the various functions that it can perform with regards to movement and exercises and then look at how we can look to bias an exercise towards this particular quality within a specific exercise. We all know that in every movement we perform everything works i.e. the trunk is working in all exercises and movements and therefore one can make an argument that we don’t need to incorporate trunk specific exercises. I don’t totally agree with this as there will be times that focusing on specific trunk exercises may actually assist an individual in their sport or exercise.
Lets take the powerlifter for example, time after time I see powerlifters whose programs are primarily bench, squat and deadlift with little accessory work and eventually these individuals either plateau in their improvement or they develop training related injuries. I believe this is probably related to the programming side of things that results in an overuse injury developing or an imbalance in the training leading to guess what, an overuse injury. In some cases a lack of variation may also result in not challenging the body with regards to stimulus and therefore lead to a plateau. So what and how does this relate to trunk exercises for example or any other accessory focused exercise. The trunk exercises or other accessory exercises can be used to address any imbalance (deficit) that has been assessed or observed. Incorporating a range of accessory exercises such as the trunk variations can also be used as an assessment in its own right and the individual will be able to compare left to right for those trunk exercises performed across both sides of the body. In addition to this we are also adding variety and a different training stimulus that may assist in keeping one mentally engaged and the body needing to physiologically adapt.
So what are the different roles ones trunk can play:
Bracing: Lets take a quick look at many conventional S&C exercises i.e. deadlift, squat, overhead press, lunge, split squat, bent over row, seated row – all of these require trunk stiffening to maximise the body’s ability to general strength and power from. In many sporting contexts the body will also need to be able to brace appropriately (the right amount at the right time).
Anti rotation & side bending: Lets take a look at many conventional S&C exercises i.e. deadlift (especially with a mixed grip deadlift), squat, bench press, any single arm push/pull exercise that incorporates the horizontal and vertical plane, any asymmetrical load in a single leg RDL, split squat, step up or lunge pattern requires the body to stabilise and control the rotational force. In many sports contexts one will also need to brace and control rotation (again the right amount at the right time).
Rotation: This probably relates more so to many sporting or movement pursuits where rotation (movement in the transverse plane) is required i.e. any racquet sport where one must be able to rotate and time the use of the trunk in conjunction with the hip and lower limb as well as the shoulder girdle and upper limb.
Flexion/Extension: Our trunk needs to be able to flex and extend in many various exercises we perform as well as sporting contexts and we must have appropriate control and force development to be able to do both.
In the videos below you will see a few different trunk focused exercises that look to incorporate some of the focus points highlighted above. Please note, these are just some ideas are there are many ways to skin a cat as they say that could look to try out.