An Acute Bout of Self Myofascial Release Increases Range of Motion Without a Subsequent Decrease in Muscle Activation or Force.
This research article on self myofascial release, specifically on the use of foam rollers, is one of the first to study the effectiveness of foam rollers on ROM and strength. Many therapists and strength coaches use foam rollers in their daily treatments or workouts but little evidence has proven its effectiveness. This study had a small sample size (11) but did show increases in ROM at 2 mins and 10 mins following foam rolling. At 2 mins flexibility was increased by 12.7% and at 10 mins flexibility was increased by 10.3%. Additionally, foam rolling did not decrease voluntary muscle activation. This is important to note because static stretching and massage have been shown to decrease force production.
Obviously there needs to be more studies with larger sample sizes but this begins to give some credibility to foam rolling. Many trainers and therapists swear by foam rolling for multiple different reasons and now there is some evidence behind it.
Scapular positioning assessment: Is side-to-side comparison clinically acceptable?
Scapula positioning has been considered a very important component of a competent shoulder examination. Assessing scapula positioning can tell us about possible decrease in the subacromial space depending if the scapula is anteriorly tilted at rest, for example. However, when dealing with overhead athletes, is scapula positioning ever "normal"? This study, from the Manual Therapy Journal, aimed to look at the reliability of assessing side to side comparisons of scapula positioning in healthy, young adults.
What the study produced was that the scapula on the dominant shoulder showed greater retraction(P<0.001; (p)=.68) and upward rotation(P<0.001; (p)=.70) at the three resting positions in the study (rest, hands on hips, 90 degrees of shoulder abduction with IR). However, the interesting part was during shoulder abduction from rest to 90 degrees, retraction, upward rotation, and posterior tilting were similar bilaterally. This raises the question: With our overhead athletes who typically have different resting positions of their scapulaes, how much do we try to change?
Now, we also have to take into account this study sample was relatively small (14) and that previous studies have suggested that scapula positioning is extremely important (see Reinold, 2009 for example), but it is something that we should ponder. When assessing our overhead athletes do we know if there was scapula dyskinesias before injury or was that their normal positioning due to their dominant arm?
Any thoughts? Any experiences? Feel free to comment below.
Patellofemoral Pain Syndrome has been a topic of debate for some time now. With limited diagnostic evidence, clinicians don't have much to go off of for definitively ruling in PFP. More often than not, clinicians use a long subjective history and ruling out other pathologies to aid in their diagnosis of PFP.
PFP has two primary contributors: increased reaction force and decreased contact area. Goodfellow & Hungerford ('76) described the PFP mechanism as: patellar malalignment----reduced contact area/uneven distribution of PFJRF----increased PFJ stress/articular cartilage degeneration-----subchondral bone subjected to abnormal stress.
Fulkerson (2002) described the assumed relationships of PFP mechanism. The 6 structures that were possible pain generators: subchondral bone, retinaculum, synovial lining, muscle, nerve, skin. In 1976, subchondral bone was considered the main source of pain, and in 2002 it was still considered the primary source of pain.
The hypotheses of biomechanical reasons for PFP consider both structural malalignment (ex: femoral anterversion) and dynamic malalignment. There are two theories for the dynamic malalignment.
Theory 1: Patella moving within trochlear groove. The potential lateral displacement and/or tilt of the patella especially during terminal extension and therefore pain is potentially generated by inappropriate tracking during functional movements. Theory 2: Femoral movement under the patella--tibiofemoral rotation (transverse plane) (Power 2003, Lee 2003, Wilson & Davis 2008, Bolga 2008, Souza 2009).
All of this brings up the question of whether certain running mechanics can contribute to PFP. This study prospectively looks at female runners for 2 years, tracking them for injuries after studying their gait. The results of the study confirmed significant hip adduction was found in those who developed PFP. Hip internal rotation angle and rearfoot eversion were not found to be significantly different. What we can take away from this study is that those who develop PFP can have altered hip neuromuscular mechanics and therefore we need to consciously work on correcting that during treatment or before injury.
For those of you who have read Movement, you have probably read chapter 15 where Gray Cook discusses his 10 movement principles. Gray has started a blog on these 10 movement principles in more detail to clarify and add to what he had in his book. So far he has spoken about the first 5 movement principles. I encourage you to read up/listen to his points thus far and continue to as he posts the rest of the principles each Tuesday. Whether you believe in his philosophy or not, hopefully it can give you a new idea or a different way to look at movement and injury.
1. Seperate painful movement patterns from dysfunctional movement patterns whenever possible to create clarity and perspective.
2. The starting point for movement learning is a reproducible movement baseline.
3. Biomechanical and physiological evaluation does not provide a complete risk screening or diagnostic assessment tool for a comprehensive understanding of movement pattern behaviors.
4. Movement learning and re-learning has hierarchies that are fundamental to the development of perception and behavior.
5. Corrective exercise should not be a rehearsal of outputs. Instead, it should represent challenging opportunities to manage mistakes on a functional level near the edge of ability.