Updated: Nov 26, 2021
I’ve shared several articles/videos over the years discussing various aspects of the fascial system and how it’s involved in training. But it only just recently occurred to me that of all things I’ve posted, I don’t really have anything speaking directly on the fascial slings themselves- which is an important subtopic within the fascia discussions. And with that, I wanted to put a quick article together that very directly and clearly outlines what the term fascial slings means, and then how to consider these anatomical landmarks in sport and training.
What are the Fascial Slings?
I suppose the term itself, fascial sling, is a reasonably nuanced and modernized terminology. As far as I know, this is a new phrasing that has started to circulate the physical therapy, bodywork, and strength training communities. In a nutshell, a fascial sling refers to an anatomical landmark whereby a higher concentration/density of fascial bands span the torso (diagonally) and extremities (helically). These dense fascial bands span the torso like seat belts, running from the shoulder to contralateral hip on both the front and back sides of the body.
There are four primary fascial slings- including the anterior (oblique) sling, posterior (oblique) sling, deep longitudinal sling, and lateral sling (as shown left to right in the graphic above). The fascial slings play critical roles in posture/positional strength, basic motor control, global stability, force expression, and force/torque management. In a sense, the fascial slings are something that uniquely make us human and, interestingly, fascia is one of the areas more research is being done in the AI realm. It’s been proposed that fascia is what gives us our most “humanistic” traits with regard to movement. The overall theory being that a better understanding of fascia will help researchers and developers to “humanize” robotic movement.
Each independent sling has a set of individual/particular functions, however in a broader sense the fascial system has immense roles and responsibilities for movement. The fascial system plays an integral role in global coordination and control, movement sequencing, and kinetic integrations (particularly involving transfer of force from lower-to-upper/upper-to-lower extremities). Fascia provides us with robust elastic strength and stretch capacities, and the slings are strong examples of this. I look at this elastic potential as a force amplifier, and when athletes become proficient in utilizing the fascial system in movement, it can improve their ability to summate force.
There is also a movement subtlety involving the fascial slings that I refer to as coiling (credit to my guy Tim) that involves a conscious, but slight rotation of the trunk by closing the shoulder off towards the contralateral hip. Moreover, this concept is rooted in what we know as the “spinal engine theory", which was popularized by professor Serge Gracovetsky. This theory suggests that there is a reciprocal and rotary nature to all human movement. And with this, the fascial slings are integral for promoting intrinsic stability and co-contraction between both left and right and upper-and-lower halves.
An even simpler way of understanding this is to observe it as a counter-rotation effect that is organic to human movement. In essence, every action produces and equal and opposite action. With rotational trunk work for example, I cue my athletes to emphasize the “opposing action”. So, for something like a cable chop, (from left to right) rather than just cueing the athlete to “squeeze their hands to their right hip”, I will also add to “drive their right shoulder back as their hands move”. This keeps them conscious of the full rotary trunk action being undertaken, giving them a more robust sense of stability and broader window to utilize movement strategies.
The involvement of the fascial slings in human movement and sport actions is expansive; no differently than the musculoskeletal, nervous or any other system. However, I do believe we have become far too siloed into the conventional approaches. Most notably, the archaic anatomical perspective, which has led to our industry retaining an overzealous focus on training the muscular system and doing so exclusively in the three cardinal planes. The reality is, human movement is just more sophisticated than that, and our concepts and applications need to start reflecting our improved understanding of the human body- to include the fascial system.
It should be observed that the fascial slings can be trained for their individual components, however, because of their collective global impact, there really isn’t much demand for “specificity”, at least not when it comes to exercise selection. Point blank, the slings are wide reaching, so it’s not difficult to emphasize this in training. Where the difference lies in my opinion is the way in which movements are coached, instructed, and progressed, such as with the chop example above. There are also simple adjustments such as changing the position we work from, the cadence of movement, or applied tempo. For instance, using a kickstand set-up for deadlifts/hinge patterns rather than bilateral to put more emphasis on the lateral and deep longitudinal slings. Another example being something like a pulsing lunge, which creates more of a reflexive demand. Little subtle adjustments like these not only get the slings more involved in movement, but I’d argue are more reflective of natural sport actions as well.
For all intents and purposes, anything can be “sling or fascia dominant”, but when we’re trying to specifically target the slings, here are a few general parameters to look at:
-Movements should be unilaterally dominant; either contralateral based (right arm + left leg) or ipsilateral based (right arm + right leg). Contralateral movements will be more oriented to the anterior/posterior slings, while ipsilateral work will be more emphasized on the deep longitudinal and lateral slings.
-Broadly consider movements that are more open-chain, cross-body oriented (“coiling”), and do not provide a high degree of external stability. Remember that a major function of the fascial slings is to optimize intrinsic stability, so for the sake of emphasizing in training, we don’t want to do too much that provides stability for the athlete.
-Any locomotive, primitive, crawling based pattern will be anterior and posterior sling dominant by virtue, just as any single-leg, bending, or rotary action will emphasize the lateral and deep longitudinal slings. However, from these base fundamentals, we can use an array of strategies to increase the demand on the sling structures. Simple ways to do this include adding an offset band, use reciprocating patterns/movements, or combination patterns (i.e., lateral lunge to crossover step-up).
And please bear in mind that, as I mentioned, there doesn’t need to be a host of goofy band drills or abstract movement patterns to be deemed “fascial sling dominant” … these structures are always involved and always working during movement. Emphasizing the fascial system is as much a perspective of movement as it is application of exercise. Simply modifying our general training principles in subtle ways that can place more demand on the slings is perfectly sufficient.
Programming Sling Work
Much like the training applications, programming for the slings is largely up to your interpretation and priority. I look at general program efficacy in a very simple way:
Warm-up/movement prep: Get your mind right, move your body
-Virtually anything is fair game. But for me- tissue activation, movement flow, ISO’s, groundwork, carries
Primary Block: High load/high force compound movements
-Squat, pull, press, clean, jerk
Secondary Block: Variable, but mostly high force unilateral compound movements
-Split squat, kickstand deadlifts, split press, split cleans, split snatch (*also good opportunity for offset loading)
Tertiary Block: Lower force/higher speed, movement sequencing, and multiplanar
-Hinge patterns, rows, lunge/step-up variations, etc.
If we analyze training from this perspective, there are three segments of training that I place my sling work. Those three being the warm-up/movement prep block, performing as intraset options (between sets during primary block) and as accessory work. So in my opinion, get your strength and high force work from your big lifts. But then, rather than just using redundant “filler” type of movements (DB bent row, BB RDL, DB Bench, etc.) in your remaining blocks, approach this with more of a fascia-based mindset. I feel this gives the athlete more opportunity to be in positions that are reflective of sport and help them to better understand how to utilize their fascia to their advantage.
A final note, as shown in the graphic above, emphasizing the fascial slings for return to play (RTP) athletes can be a highly effective strategy. Quite frankly the efficacy of sling work for athletes coming off injury is absolutely at the root of what I do daily. What I’ve noticed with injured athletes is the pressing demand to improve global stability, and the impediments that compensation patterns and non-functional imbalances have once the injury has fully healed. With this, I take a proximal to distal approach, and work to reduce the amount of difference between sides (resulting from the injury). Re-balancing the movements from the trunk outward has been a very effective strategy for me for reducing the presence of non-functional asymmetries, subjective reported pain, and strength/mobility measures.
Collectively speaking, fascia is very much a “real thing”, and it’s probably something you haven’t given enough attention to in your training/evaluation. Listen, I can understand coaches and practitioners having reservations about how much the fascial system may be involved in movement/performance, but to suggest that “because we can’t measure it” or because the formal/scholarly research is lagging that it suggests fascia has no or minimal involvement in performance is simply ignorant to me. Human anatomy is a vexing curriculum, and one that is continuously expanding. I’ve been steadfast in believing that we are still in an infancy phase of understanding our own bodies. So it’s a safe and reasonable assumption to suggest that we may be on the cusp of a massive breakthrough with our evolving understanding of fascia. But I digress.
If nothing else, understand the significance of contralateral and unilateral movements in training. Don’t train your athletes like powerlifters or body builders, allow them to be and feel athletic in training. More rotatory based actions in lieu of stiff rigid positioning. More open-ended, combination movements, less closed compound movements with constraints. And lastly, emphasize the elastic nature of movement, and encourage athletes to utilize this concept to the best of their ability.