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Nike concept of elite athlete inner-space travel. Photo Credit Teague.

Editor’s Note – I wanted to interview Dr. Cagle because the challenges astronauts experience are extreme and mirror what elite athletes must face. Above is Nike’s vision of “inner space” travel for elite athletes, including an indiboard or personal dashboard for monitoring recovery during travel.

Dr. Yvonne Cagle was a member of the Astronaut Class of 1996 (NASA Astronaut Group 16). She is currently assigned to Johnson Space Center’s Space and Life Sciences Directorate. Dr. Cagle is also an advisor for NASA’s Flight Opportunities Program (originally named CRuSR – Commercial Reusable Suborbital Research Program. Currently, Dr. Cagle is on faculty and serves as the NASA liaison for exploration and space development with Singularity University. During the workshop, Dr. Cagle was embedded with the crew as a crew training consultant and advisor, providing insights and feedback to both crew and study team from the viewpoint of an astronaut, flight surgeon, space development expert, and science liaison. (Source Wikipedia)

Dr. Cagle’s responses are conveyed as her opinion only, and in no way reflects the position of NASA or the Astronaut Office.

Athlete and Astronaut Recovery

Freelap USA – Space is a very hostile environment. Long term microgravity or weightless environment has shown to increase “astronaut blindness” or optic nerve problems. Much of this is due to the lymphatic system needing ground based contractions that are missing from foot strike, acting like a second heart. How would you plan to use exercise to improve lymphatic kinetics during long space flight to destinations such as Mars?

Dr. Cagle – Theoretically, increasing cardiac output by way of aerobic exercise weighted (no pun intended), by centrifugal loading to induce a force multiplying stressor, could reflexively enhance renal perfusion and induce potentially a diuresis that could, in turn, serve to off-load lymphatic hydrostatic pressures. However, a cautionary note is called for in that it would require maintaining a new steady-state that did not induce a relative volume contraction to the physiologic state. Hence, judicious re- or “eu”-hydration would be necessary. The precise titrations and recalibration of the translocation and redistribution of fluid between physiologic compartments could benefit from extended bed rest studies in order to assist in demonstrating concepts of the dynamic physiologic interchanges.

Carl’s Take – The use of recovery workouts and devices, such as the pneumatic compression pants, must be very precise, or they will backfire. For years, I have seen recovery modalities delay healing (poorly prescribed tempo runs) or provide no physiological benefit. One NFL team is currently using a sequence of pool workouts, EMS, and Normatec devices. I believe that the inflammation and pain biochemistry models now can understand internal chemistry better, so we are no longer using outdated neuroscience models that are simply input / output based. Inflammation is about normal waves that allow for adaptation, not tsunamis. To create a workflow, I suggest using the combination of blood testing, GSR, and HRV monitoring and MyoAnalytics.

Edit- Living in space can create a problem with the lymphatic system, and this is caused from intracranial pressure likely from lymphatic interactions. A different but similar problem happened to Chris Hadfield while in space, and his TED talk What I Learned from Going Blind in Space was excellent. Dr. Cagle also presented at TEDxBrussels.

Pneumatic Compression

Figure 1: Pneumatic compression is growing in sport, and some new research is hinting that other mechanisms besides blood flow and lymphatic kinetics are occurring. Some studies are leaning towards other chemicals that mediate pain from the neuroendocrine system. How effective all of this will be explored when more research is done.

Galvanic Skin Response Measurement

Freelap USA – Monitoring is trending in sport now, and you have major challenges being far away from your athletes, the astronauts. They are not only out of state; they are out of the planet! How important is the system monitoring to allow the user to be empowered? Waiting for communication is always an issue since the receiver of the information has to be able to make a decision. How do you see the individual being educated on recovery of the Autonomic Nervous System by looking at GSR and HRV? Now GSR is growing in momentum again; what are your thoughts on self-management of stress and recovery?

Dr. Cagle – HRV and GSR can serve as reflections of the autonomic nervous system’s health and performance state of the cardiovascular and pulmonary vascular systems, respectively, including their systemic metabolic responses. And such physiologic markers can also serve as important signposts for the updating, recovery, and training of an autonomic drift due to illness or other stressors to the human systems.

Providing a suite of preferably wearable biosensor tools that enable real-time, self-monitoring feedback to such rapidly correcting autonomic systems centralizes point of care and allows the individual to leverage a personalized readiness platform and make timely, adaptive interventions that could ultimately recover or optimize performance.

Carl’s Take- GSR provides the opportunity to get the sympathetic side of the athlete’s story. Landon Evans tweeted about the inflammation model for acute fatigue and he is right on target, but what is scary is the discussion of using medical implants to stimulate the vagus nerve to hack the nervous system through a mobile device. A better way is to regulate the training load and environment to be more favorable to recovery and manage the stresses of life versus the reaction to the stress. Steve Magness and I shared the paradigm shift towards a holistic view of training and included GSR in our blogs and writings.

Assessment of Physiological Load

Figure 2: Physiological load is not the only variable with athletes, and the emotional and medical variables require other data sets as well as extra interpretation. Above is the data spread of readiness using the Check device and the data appears to explain the professional athlete’s end of a career because of severe injury.

Monitoring Travel Stress with Technology

Freelap USA – With available space inside a cockpit and living quarters during extraterrestrial missions, you likely to think very far ahead to creating a currency of how effective a recovery device is based on the physiological response, the size of the system, the reliability, and other factors. While Moneyball may be looking at economic impact of player effectiveness based on their pay, the real issue for NASA is the value of anything onboard and helping the astronauts. With new sensors like Angel being small and able to export to mobile devices, how is the start-up community disrupting NASA and labs with getting high-quality data with consumer-friendly designs?

Dr. Cagle – Wearable technologies for biosensing and training are not only the wave of the future, they are the way to human participation and performance optimization in the exploration and colonization of deep space. Moreover when integrated onto a platform that can support and organize the data to be coupled to algorithms engineered to aggregate and update physiologic trended profiles, these biosensors can then cross talk in such a way that data can be streamed, stored, and/or shared to a sky drive and/or archived for subsequent data mining. The resultant build-in could produce designer predictive models tailored to target and customize the personalized point of care for health and readiness of long-duration crews and the individual crew member.

Angel Sensor

Figure 3: Angel Sensor

Carl’s Take – I am very interested to see what happens in the future with CoachMePlus and TeamWorks as both are poised to make a wider adoption. One challenge with CoachMePlus is that they are not medical compliant yet, and TeamWorks has limited performance tools of the software. On the flipside, we still need better hardware options that use sensors properly to get valuable data. The Apple watch is a step forward as predicted by Steve Jobs years ago, but the execution in the next few years requires more sensors and better user experience. New services like Teambuildr (not a typo) are budget friendly levels and expect a price war.

Open source options like the Angel Sensor are going to be mainstream in the next few years, and having an API for coaches is going to be the first question anyone has before doing team orders. At the BSMPG Summer Conference, one sleep device was completely ruined because of the outdated algorithm by a leading speaker, and the future will include less wearable devices, but more passive options that are similar to surveillance.

Space Age Technology and Medical Sources for Recovery

Freelap USA – Parkinson’s and other diseases are likely areas that most coaches don’t study, but are likely to be future areas where dopers in sport will look for advantages. Looking at creative ways to prevent overtraining and improve development with athletes, where do you see smart ways to help both disease and sport with science? I am sure the difficult challenges of microgravity are likely areas that can help sports medicine and aging diseases to the brain?

Dr. Cagle – Performance including that of the brain is on a continuum that stems from the human body regardless of the environment the individual is performing in-be it space, sport, injury, illness, or aging. The capacity of the brain’s neuroplasticity to regenerate itself and or establish compensatory pathways is even more intriguing and an emerging area of research and technology development. The commonality shared between venues of space, sport, and neurodegenerative conditions create a nexus of complementary analogs that can advance our understanding of and interventions for neurodegenerative processes.

Carl’s Take – Aging and space travel have similar obstacles such as muscle wasting, and athletes have injuries that can benefit from evaluating tissue. What is interesting to me is the use of MyoAnalytics and the Myoton device used for experiments in space travel and living. If an athlete is lean enough to measuring tone (stiffness and elasticity of muscle precisely) can be done within seconds. It’s important to know that TMG uses electrical muscle stimulation and the data while similar, represents more neuromuscular responses, but I predict will be consumer friendly in 2015. While the MiSensor from Compex is not perfect, it does have some overlapping data because of the accelerometer and EMS interaction.

Myton Device

Figure 4: The Myoton device is a rapid and research grade tool that assists in tracking changes with tissues such as muscle. It’s sensitive to evaluate a baby’s skin and smart enough to detect changes on tendon as well. It’s amazing how few teams evaluate readiness of tissue and are barely using anything to get clear information on how muscles are recovering and changing from training and competition.

Edit: Usually, I ask more questions in an interview and wanted to include the Swedish hamstring information because a lot of connections to Sweden through interviews and seminar reviews are very obvious. Another connection is Dr. Cagle on YouTube with Spaceport Sweden, a concept that is now available with SpaceX and other options. Finally, NASA used the research and science from one of Sweden’s top physiologists to help come up with non-gravity based solutions.

Space Age Hamstrings

One of the top ways to reduce hamstring injuries is general eccentric strength to the hamstrings and posterior chain. Nobody will deny that sprinting helps, but complimenting speed training with hamstring development works. For years, everyone has looked at the Nordic hamstring exercise as a way to decrease tears, and they seem to work in soccer. The reason? Many soccer programs skip the weight training and so the research usually compares doing the exercise to not doing anything at all. With many clubs in elite soccer still try to catch players and redirect them after stepping off the pitch like escaped convicts, Nordics made sense.

Nordics don’t need equipment and can be done on the field, something very practical when training large groups. So the exercise being popular makes a wise intervention but what if Nordics were compared to other options? Many athletes have tightness and discomfort behind the knee when doing the exercise, and the research doesn’t show them to be the best options compared to other tried and true methods. For example, noted world expert on hamstring injuries, Carl Askling, showed the use of the eccentric tool (kBox) made a major impact with reducing injuries in his research.

Figure 5: kBox Lunge

Figure 5: kBox Lunge

Most readers realize I am a minimalist to exercise equipment and after years of talking to Hakan Andersson and visiting his facility, I realized I was biased against machines and needed to accept the evidence. The EMG recordings and biochemical changes of the flywheel are better than Nordics for several reasons.

Higher Velocities – Motor control research supports the differences between slow and fast contractions and higher speeds matter. A well-rounded program will not have problems with imbalances in training, but getting enough training with so many limitations of team sports coaches want something that gets the job done.

Coordinated Movement – Contraction is the yin to the relaxation’s yang. Rapid speed squats are not going to make one faster, but the integration of speed work and not grinding out squats will help remove stereotypes that can cause dead spots while sprinting. Heavy and slow squats are not evil; it’s just you can’t have a steady diet of them unless you have a lot of speed work. Leaving the weight room after a heavy set of squats should not induce fear that one is training slow, but stepping back and seeing distributions of training modalities can show why injuries occur. Speed squats are not performance enhancing, they are more injury reduction.

More Exercises – A comprehensive program includes enough variety in the program to remove staleness and address all function of the three hamstring muscles. Single leg, double leg, lateral and frontal all matter. Nordics are one option, and while that is an effective one, it’s not comprehensive.

I think small doses of using the kBox are worth the investment, and it’s far better than the belt squat machines of the past. I think the real popularity of the kBox is belt use, removing the risks and burdens of squatting soccer players. This is not an attack on European football clubs; it’s just the culture of the sport not wanting to touch barbells. I will write more on the research on hamstrings and applied solutions that most will agree on, and I think the use of flywheel equipment is worth investing into if you are a school or professional team.

Please share so that others may benefit.


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