As far as injury prevention goes, we talk a lot about trunk endurance. And rightly so as the is evidence supporting the ability of the trunk muscles to perform for a long period of time and support the lumbar spine, pelvis and hips to prevent injury is positive and conclusive. But like any advancement of knowledge or practise, things need to be taken further.
So what do we do with an athlete who has already achieved what we would consider a good level of trunk endurance with the common exercises at your disposal like planks, (front bridge) side plank (side bridge), back extension hold etc. Firstly, you can increase it further because you can never have too much trunk endurance and the increased endurance will only serve to further prevent injury. However, for ongoing performance improvement in terms physical capabilities, systems need to be continually challenged and overloaded for the necessary adaptations to take place. In this case being the ability of the trunk muscles to work at the highest level possible to prevent injury and to hold the dynamic posture required by the sport for a high number repetitions under increasing fatigue.
There is much room for improvement in both knowledge and practise on how we can achieve this. Look to progress the basic trunk endurance exercises to more complex versions to challenge not only trunk endurance, but also neuromuscular control, the ability of the body hold posture with less support or under more unstable conditions and recruit more concurrent muscles to stabilise the body in the desired position. Then look to increase the holding times or repetitions of exercises and then again look to again increase complexity, decrease support etc. And this is an ongoing process as the athlete continues to improve. Not finding ways to challenge and progress an athlete will cause stagnation in the performance of the stabilising systems. This is very relevant for both end stage or high level rehabilitation programs and as part performance training programs.