By Lachlan Wilmot, Athletic Performance Coach at the GWSGiants.
Power, strength, speed, all of these are sort after abilities in a majority of sports around the world, but are we chasing the golden egg before looking after the chicken? Within team sports, one of the most common thread among successful teams is the relatively low changes made to the starting line-up from week to week. This makes sense as it means the coach has his/her best squad available for selection, could this mean availability is perhaps the best ability for an athlete?
Soft tissue injuries and in particular hamstring strain injury (HSI) is a leading cause of missed games within numerous team sports around the world, what’s more, it is as with all soft tissue injuries, once one is sustained, the likelihood of sustaining another is significantly higher. This inability to resist further muscular damage is something that should be of primary focus to a strength and conditioning coach.
Damage resistance concept
Damage resistance is a term that has been used lately to describe a muscles ability to produce high levels of contractile force and therefore reduce its likelihood of sustaining microdamage or tears, with particular reference to the hamstrings. With the arrival of the NordBord, a useful tool in quantifying the hamstrings ability to produce force, there has been numerous research papers that have started to demonstrate a protective effect provided by hamstring strength. This finding doesn’t just pertain to uninjured hamstrings and the prevention of HSI, but to previously injured hamstrings that have acquired a large degree of strength back and have shown to have the same likelihood of injury as an uninjured hamstring. These findings create a strong foundation of reasoning for contributing time within a strength program for the improvement of isolated hamstring strength. With this said, how do we go about being prescriptive and targeted with our programming so as to elicit the best damage resistance response?
Distal and Proximal Approach
Due to the biarticular nature of the hamstring group, HSI can present either distally or proximally, both of which can occur with very different mechanisms and therefore need to be guarded against from a joint by joint approach, not just a hamstring approach. For this reason, we can break up our exercise prescription into proximal and distal orientated movements, therefore allow us to periodise accordingly.
Distal or knee dominant hamstring exercises can be seen as those that isolate the movement to flexion and extension at the knee joint, loading the distal attachment of the hamstring. Proximal or hip dominant hamstring exercises are those that are created from extension and flexion of the hip joint, therefore isolating the loading to the proximal attachment of the hamstring. These two isolated movements allow us to specifically overload the desired areas, the third category of movement is an integrated exercise. This utilises the active lengthening and contraction of the entire hamstrings group, both distally and proximally. Integrated exercises are ultimately what we want to build up in our athletes, but to achieve this we must periodically overreach with our distal and proximal movements. This is the basic premise of our periodisation model, allowing structured overload of both the distal and proximal attachments, building that foundational strength for integrated progressions.
Loading / Programming
Figure 1. Example 12 week periodisation model. PD: Proximal Dominant; DD: Distal Dominant; INT: Integrated; EF: Eccentric Focus; BAL: Balance.
In Figure 1 we can see two examples of periodising for hamstring damage resistance, in the top portion, we can see a layout for three 4 weeks blocks. This would be a Proximal Dominant block, into a Distal Dominant block finishing with an Integrated Dominate block. These can be further broken down into 2-week blocks for each phase, with a 2-week focus on Eccentric loading (eg. Nordic Curl eccentric only) and then a 2-week balance between concentric and eccentric loading (eg. Nordic Curl band assisted to allow up and down phases). This loading scheme would then repeat each block thereafter.
In the bottom portion, we can see a slight variation, where the Proximal, Distal, and Integrated blocks are only 2 weeks, but the Eccentric focus would continue across the 3 phases before the Balanced loading would be utilised for the next 3 phases. These are just two simple examples of periodising to allow an integrated approach to build damage resistance, but adjustments may need to be made to fit in with your individual setting.
When building isolated hamstring work into your current program, it is important to ensure it doesn’t reduce output within other lifts, but also isn’t left as just an add-on that athletes’ view as a non-essential. For athletes to get the most out of this style of exercise, a good buy in must be bred to allow maximum output during eccentric aspects of loading, this is best done by treating the exercises as almost a key lift, usually positioned in the middle of a sequenced program, allowing large compound movements and plyometric work to be done first.
In regards to frequency of these exercises, two times per week looks to be an ideal loading strategy, but in-season, sufficient load can be achieved by one exposure to allow a protective effect to be maintained. One of the most important aspects to remember is each rep of most of these type of exercises are near maximum efforts, and therefore should not be prescribed at high intra-set volume, rep ranges of 3-6 appear to be most effective, with sets ranging from 2-4.
The concept of damage resistance and building a protective effect around hamstring musculature is becoming more abundant, and with this there needs to be logical and effective principles for integrating into current programs. These type of exercises do not replace the need for large compound lower body movements or well coached running mechanics. However, this type of training can build significant resilience to the exposures seen in team sport and thus contribute to the availability of players.