Aaron Davis is a sports performance/health coach with 10 years’ experience coaching athletes and teams across multiple sports. Aaron firmly believes health and performance go hand in hand, and he utilizes multiple diagnostic technologies and labs. He is a constant student of sports performance and health—drawing upon knowledge from leading experts in the field.
Aaron coaches athletes in the Austin, Texas, area, as well as international and U.S. athletes remotely. He shares his experiences and training philosophy by speaking at seminars and writing for Train Adapt Evolve.
Freelap USA: What is the role of blood oxygen levels in determining how a particular workout will impact an athlete?
Aaron Davis: Oxygen gives us a proxy on the bio-energetics of the cells, specifically how the protein-ion-water system of the cell is behaving. Regardless of the physiological reaction we are aiming for during a workout, monitoring O2 can assist with understanding load (e.g., knowing when enough is enough).
In regard to training density, frequency is a powerful adaptive stimulus. However, there are too many times we can’t take advantage of it because we overdose workouts for the sake of the workout looking sexy or our admiration of our own coaching ego on paper. These workouts generally elicit emotional responses from the athletes that satisfy some small spot in us as observers.Monitoring O2 can assist with understanding load (e.g., knowing when enough is enough), says @DavisXCTF. Click To Tweet
They also push peripheral adaptations of mechanical proteins while underdeveloping the energetic components to support the extension and/or quality of work in the future. The upside is that in 50 years, the athletes will have a dossier of heroic workout stories as they pop wheelies in the nursing home and giggle about the good ol’ days.
Circling back, O2 allows us to know how the protein-ion-water system is behaving via its close ties to phosphocreatine, with O2 recovery running close to parallel with the phosphocreatine (PCr) system (McCully 2013). Since PCr is the first on call when it comes to ATP resynthesis, having a proxy on PCr is important considering that the ability to also resynthesize PCr from glycolysis and the oxidative system keeps the cell in a “ready state” (cellular retention of K+/protein unfolding). The excess loss of K+ may be a signal that cells are no longer in the ready state, but are in a state of fatigue (meaning the cell will need to take time to regenerate or regain its ready state). The feeling of soreness may govern this process.
Freelap USA: How do you monitor oxygenation, and how do you steer the course of training based on your findings?
Aaron Davis: I use a technology called Moxy to monitor oxygenation, though the Omegawave Team system can also tell the story of the O2 environment the muscle will encounter. This is monitored by the gas exchange reading showing either normal or hyper/hypoventilation present (shifts of the O2 dissociation curve).
Apart from stopping a workout once the physiological stimulus is reached, as mentioned above, monitoring muscle oxygen saturation (SmO2) and total hemoglobin (tHb) will give an idea of the readiness of the peripheral system for metabolic work. If central mechanisms are in place but low SmO2 shows up in the periphery, we generally will not target a HIIT metabolic workout; instead, we train what’s ready.
As for allowing SmO2/tHb to guide the workouts, we look for specific reactions to elicit an adaptation. For example, if we are to improve a cardiac limitation then I am going to monitor a low-priority muscle. During the workout or interval, I will work up to an intensity (e.g., frequency of coordination, velocity, or power output) before a compensation takes place. In a non-priority muscle, compensations will look like a decrease in total hemoglobin, SmO2, or both. If we push the cardiac system too far, it will limit delivery to non-priority muscles by shunting blood to the priorities.
Over time, we push this threshold further and further in resistance to fatigue and power output. One caveat: I also monitor respiratory rate and depth because that matters and it doesn’t have to be solely nose breathing, contrary to what is out there. It’s all about the relationship between the heart and lungs.Blocks don’t have to look that different from one another—it just takes slight nuances between them, says @DavisXCTF. Click To Tweet
Setting up blocks of training underneath this idea of “limiters” of performance is quite simple.
- Block 1 – Improve the Limiter
- Block 2 – Improve the Limiter
Blocks don’t have to look that different from one another. The whole focus in training regardless of demands (speed, power, endurance) is to do what matters for the athlete. Refine the process and cut out the BS. Therefore, slight nuances between blocks are all it takes.
Freelap USA: What tools do you utilize to monitor fatigue in athletes? How does it depend on the type of athlete you are working with?
Aaron Davis: The major players are Omegawave and Moxy, though we do run lab tests, nutrition recalls, phase angle, orthopedic measurements, gait analysis, and electrophotonic imaging (EPI).
Fundamentally, we always look at health regardless of the athlete’s objective. It helps us as a team combat time (which is always an adversary when it comes to preparation). I am not a big believer in the existence of overtraining anymore, but more so in energy allocation. I have spent way too much time with people that, on paper, shouldn’t be functioning normally, let alone performing well, yet they still do.I am not a big believer in the existence of overtraining anymore, but more so in energy allocation, says @DavisXCTF. Click To Tweet
With that said, “functioning normally” is a bit blurry, but if performance is your objective, energy may need to be stolen from other systems to support the main drivers. This is where monitoring can really help make better decisions. Again, time is your adversary in this situation—the allocation of energy and the undertraining of other systems will only come back and kick you in the ass in due time. Yet, if you are aware of the trends, you can manipulate this.
Freelap USA: What are your biggest points of emphasis in facilitating recovery outside of training, as well as the lifestyle of an athlete?
Aaron Davis: It comes down to compromise and trust between coach and athlete, with an agreement that the data tells a story without emotion. We operate in steps, though my tendency is to always push. We are fortunate that we are in the private sector and operate more as a concierge service. I only have five to seven athletes on my roster for in-person training at a time. With that said, a lot of time and money will be wasted if we don’t uphold our obligations and meet our objectives both as athletes and as coaches. The environment in which we operate increases motivation to facilitate recovery.
If I had to pick one thing we tweak first, it will always be sleep. Sleep is the biological signal for energy conservation. Heat can dissipate electronic energy used for biological processes, so it makes sense that we spare energy during sleep from processes like temperature regulation and muscle tone via the CNS. Sleep allows time for storing biological energy. Without this in place, we lose time and everything expands.Sleep is the one thing we always tweak first in the lifestyle of an athlete, says @DavisXCTF. Click To Tweet
Simple fixes, and some interventions we may use, include: nutrition (carbs later in the evening); supplementation (e.g., B12 at night); no shadows after sunset (lamps instead of overhead lights—eliminating lower peripheral vision signaling); blackout curtains; temperature; exploring different mattresses/pillows; blue blockers if needed; and dead time for screens.
Freelap USA: What is your assessment process with incoming athletes, and what schools of thought do you draw from?
Aaron Davis: Every athlete that comes in fills out an extensive health questionnaire and goals/objectives, and completes a blood panel (CBC and CMP), three-day nutrition log, orthopedic evaluation, and Omegawave and Moxy assessments (strength, HIIT, and endurance protocols).
When it comes to evaluating an athlete’s physiology, our schools of thought are a mashup of PRI and osteopathic principles from a structural perspective, alongside a systems-based approach. This approach of systems-based thinking was inspired by Russian physiologist P.K. Anokhin, and has been an underlying theme within our practice for the last five years.I can’t predict emergent outcomes between systems, so we stick with what we can influence, says @DavisXCTF. Click To Tweet
It sounds fancy, but it’s really just a simple way of analyzing and loading specific systems, then seeing how they play together with their friends in performance. If they don’t, we go back to the drawing board. I am not smart enough to predict emergent outcomes between systems, so we stick with what we can influence, take notes, and repeat.
Terence E. Ryan, W. Michael Southern, Mary Ann Reynolds, and Kevin K. McCully. “A cross-validation of near-infrared spectroscopy measurements of skeletal muscle oxidative capacity with phosphorus magnetic resonance spectroscopy.” Journal of Applied Physiology. 2013; 115(12): 1757–1766.
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