Dr. John P. Wagle is a fellow in the Sport Physiology and Performance program at East Tennessee State University. He serves as the Strength & Conditioning Coach and Sport Scientist for ETSU baseball. Additionally, Wagle assists Dr. Brad DeWeese in training Olympic Training Site athletes. Wagle has been an invited speaker on a number of topics, including periodization and programming tactics, athlete monitoring, and accentuated eccentric loading.
Freelap USA: How can we use ultrasound to determine the strength and power potential of our athletes? What aspects of muscle, learned from ultrasound, play a role in power potential?
John Wagle: Ultrasound is a valuable and underutilized tool in athlete monitoring, in my opinion. Though ultrasound has several potentially useful applications (e.g., injury diagnosis, blood flow assessments, cardiac evaluations, etc.), I will stay within the scope of evaluating muscle size and architecture, as this is most applicable for the population in question. Starting with some advantages about the device overall, ultrasound is non-invasive, painless, and real-time—all important aspects within any high-performance environment.
Training-induced increases in muscle size measurements (e.g., muscle thickness, CSA) have been associated with performance changes in strength, running, and jumping—though other factors also play a role (e.g., II/I CSA ratio, neural factors, etc.). Similarly, the more nuanced changes in architecture (e.g., pennation angle, fascicle length) have been related to performance outcomes and are directly influenced by training.When creating an athlete monitoring system, an ultrasound device is a valid augmentation, says @DrJohnPWagle. Click To Tweet
Generally, greater pennation angles are associated with higher force production potential and greater fascicle lengths are associated with higher contraction velocity potential. Therefore, the “form follows function” moniker appears to have a level of efficacy warranting assessments of muscle size and architecture as informative additions to an athlete monitoring program. Such measurements may provide insight into the power production potential of an athlete and have their greatest utility when alongside other relevant monitoring tools. An ultrasound device may not be the first item on a bucket list when starting an athlete monitoring system from scratch, but does become a valid augmentation that allows for greater insights.
Freelap USA: What are the potential drawbacks of including ultrasound in an athlete monitoring program?
John Wagle: The most obvious potential drawback is the need for a skilled ultrasonographer with a background in sport science. Not only is it important to be able to collect and process the images reliably, but also to interpret the measurements within the context of the training process and other pertinent monitoring data. As is the case when aiming to leverage any technology, data analysis and interpretation become the most valuable.
Another potential drawback is the cost associated with most devices. Though we all have different budgets and circumstances, ultrasound’s utility and versatility make it an attractive addition. Versatility has its downside too, however, as recent evidence from Vigotsky, et al.and our research group suggests that collection methodologies (e.g., measurement site, posture) may influence the associations with force production capabilities.
Varying methods aside, it is also worth noting that the inferences on muscle function gained from ultrasound measurements are typically based on static, two-dimensional anatomy. Contraction is obviously more complex, as it involves muscle shape changes in three dimensions. Such differences in the direction of muscle bulging from contraction may influence the muscle’s architectural gearing and therefore its tendency to favor higher force or velocity outputs. Though this is still a highly theoretical consideration, there is value in acknowledging such a potential limitation.
Freelap USA: How does ultrasound provide context and greater depth of information to tests like the isometric mid-thigh pull?
John Wagle: The isometric mid-thigh pull (IMTP) is a great monitoring test due to its high reliability, safety, and robust data. It also fits nicely into a comprehensive monitoring program alongside supplementary pieces like ultrasound.
The proper sequencing of training is a potential debate for another time. Nonetheless, the pairing of ultrasound and IMTP within a block periodization or phase potentiation model is logical, considering the previously discussed relationship between architecture and force production.Pairing ultrasound and IMTP within a block periodization or phase potentiation model is logical, says @DrJohnPWagle. Click To Tweet
For example, when conducting athlete monitoring early in a phase potentiation-based training process, the performance team may be most concerned with changes in muscle size and in force production. As training progresses to maximal strength and then power development, the changes in architecture and in rate of force development become increasingly valuable. Because the aforementioned muscle and performance characteristics can be manipulated and leveraged through properly structured training, considering both pieces of data alongside one another may provide a deeper level of context-specific evidence with which to evaluate athlete response.
Freelap USA: What are the primary, practical ways you use force plates in jump testing with athletes?
John Wagle: This depends on the group. As part of my work under Dr. Brad DeWeese at ETSU’s Olympic Training Site, I implement a monitoring program with his athletes that involves frequent testing. To evaluate microcycle-level response, the athletes perform weekly unweighted static jumps each Monday prior to training. Additionally, they go through a more extensive static and countermovement jump protocol at the end of each block. This allows us to examine how athletes are responding to training on different scales of time—permitting a more objective examination of cumulative and delayed training effects.
I also work with the baseball team at ETSU, but take a slightly different approach with their jump monitoring protocol. Because of the size of the roster and other practical limitations (e.g., academic demands, practice frequency, etc.), we have less frequent collection. We are aiming to gain insight into the effects of training over the course of an entire semester and therefore use a more extensive protocol.
With baseball, the squat jumps move from 0kg up to 80kg in 20kg increments. Here, we look just as much at the quantitative aspects (peak power, force, velocity, etc.) as we do qualitative determinations of the curve-shapes at each load. Additionally, we examine the drop-offs from load to load and the changes from pre- to post-training at each load. From this, we can then generate hypotheses on the individualized effects of the training and use that information to guide the process moving forward.
Freelap USA: What are your favorite ways of using the Reactive Strength Index in training and testing different athlete populations?
John Wagle: We used the RSIMOD last season with our women’s volleyball program. We still have a lot to learn about RSIMOD and its efficacy, but it does present some logical advantages within a monitoring program that have been well outlined by Daniel Martinez in a few different publications.
From an acute fatigue management standpoint, RSIMOD is sensitive enough to change to be an appropriate consideration. We leveraged this with bi-weekly jump collection in-season to inform microcycle management within a relatively consistent weekly match schedule. It is worth noting, however, the jump assessments were considered alongside our periodization model, load monitoring, wellness questionnaires, strength of opponent, and other factors.RSI-MOD does present some logical advantages within a monitoring program, says @DrJohnPWagle. Click To Tweet
RSIMOD is especially interesting when considering the chronic response to training unique to volleyball athletes. Because “slow SSC” happens to be an important component of volleyball performance, I like RSIMOD as a means to assess adaptation. Stealing from Daniel, the “how high, how fast” that RSIMOD essentially describes is important as these athletes progress through the training process, especially for front row players. Therefore, RSIMOD demonstrates a level of “scalability” as a monitoring tool within a periodized training process.
We can zoom in and inform the session or the microcycle, while simultaneously maintaining the ability to zoom out and assess longer-term changes in outcomes directly related to on-court performance. This was particularly valuable as we evaluated the success of our taper heading into the post-season.
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