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Female Athlete with Electrical Muscle Stimulator

By Carl Valle

Here is my first annual review. Based on email and Twitter exchanges, it features my most requested solutions to monitoring and recovery issues. Usually, I do things like this at the end of the year in December, but I’d like to get an early start.

Monitoring Topics and Procedures


Pros and Cons of Jump Testing

The paradox of jump testing is that those not doing jump training usually need testing, while those jumping too much need conventional strength training. The NBA strangely has a high adoption rate for force plates. This is not a bad thing, but some perspective is needed in the realities of pro and elite college programs and youth academy studies with lower-level athletes.

Jump testing requires a maximal effort, and that doesn’t happen when athletes are bored or sore. They can be fresh and explosive, but the data is muddy if they have been doing jump testing for a while and dealing with residual joint soreness. On the other hand, jump testing provides direct information. Many systems estimating fatigue from physiological measures are secondary but still have a place. To know if an athlete can do something, you need to just do it and see.

Monitoring Procedures: Test without load and with load only when you can control the set-up and conditions. Athletes need to be somewhat rested, and testing for bodyweight should be no less than quarterly. Twice a month is sufficient to get basic trends with loaded jump motions like the Raptor Test. While residual fatigue from training suppresses some metrics, the goal is improving year to year, not test to test.

Quick Tip: Loaded jump tests like the Raptor makes sure coaches are managing power development in training and not rewarding talented athletes who can do a great vertical jump from being blessed with great genetics.


HRV at the Arena Versus at Home

Mobile options that test athletes remotely and give high-quality data are good options. Testing at home upon awakening removes many variables and is improving thanks to the options of camera sensors with smartphones, but most teams don’t experience anywhere near 80% daily compliance with home testing.

ithlete Pro Data Chart

Figure 1. The ithlete Pro system for mobile testing of elite and recreational athletes.

Team testing requires everyone to be at the same place at the same time, and a lot can happen between the time someone wakes up and arrives at the practice facility. Compliance rates are higher, but the data value is mixed. Also, test duration is longer, as athletes must stabilize their arousal and heart rate.

Obviously HRV monitoring has value but repeatability and validity are different, and simply repeating something in the arena doesn’t mean data integrity is high. Regardless, you should add subjective questionnaires, so follow-up questions hopefully can tease out false positives and negatives.

Monitoring Procedures: Have an organization policy of expectations. On-location team testing can be a nightmare if it’s not standardized and valid. Subjective questionnaires can align triage therapy from smartphone apps and services, and HRV can be captured using a Buchheit approach or peaceful relaxation method. Offer a combined score to those who do home testing, so team chemistry isn’t split between home-testers and those who test at the facility.

Quick Tip: Migrate to more home and personal testing so athletes increase their self-reliance on what they can do and improve responsibility for their actions.


Understanding the Biological Strain Index

Internal response is the biochemical and molecular event following external loading from training and competition. It’s hard to limit training to what someone does when the reality is that the combination of what someone does and how they respond is a recovery metric. Athletes who can do more and do it again faster technically have more recovery ability, and you can make a case that it is a sign of durability. One way to calibrate physiological monitoring options is periodic blood testing, to see how athletes respond to systematic and quantified external loads.

Inside Tracker Pro

Figure 2. The InsideTracker Pro system for managing large groups of athletes or users, showing the categories of risk for teams.

Five key biomarkers are creatine kinase, hs-CRP, total testosterone, SHBG, and cortisol. Done periodically, these simple tests show why some athletes are Wolverine and others Mr. Glass. Creatine kinase can estimate muscular breakdown, hs-CRP can detect inflammation, and hormones can look at overall stress and fatigue.

Inside Tracker Cortisol Ratio

Figure 3. An InsideTracker user account showcasing the free testosterone to cortisol ratio.

Monitoring Procedures: Do a blood test in every phase of the season: pre-season screen, early season follow-up, mid-season trends, and post-season analysis. Monthly is ideal, but logistics may dictate a different frequency. Test two days after an intense bout of training or competition, or during peak restoration recovery cycles. Merge HRV, GPS, and sleep data to determine correlations and perhaps causation.

Quick Tip: Get more from blood testing by comparing the relationships among multiple biomarkers versus hunting to see one or two outliers.


GPS in American Football

With a field that resembles a giant ruler and plays that are usually scripted, American football might seem an unlikely candidate for GPS monitoring. True, the general idea of training volume is not a mystery. But GPS monitoring is much more than total distance; it’s about the fine details of cutting and re-acceleration combined with displacement. When coaches are buying into player tracking, they are estimating the wear and tear and convenience of getting that data.

One of the biggest problems is peak velocity interpretation and acceleration scores. The issue with football is that maximal velocity doesn’t happen. Estimating work with linemen is especially hard because they are displacing the least. More importantly, team coaches often are the least educated in understanding the metabolic demands of practices and training. As a result, most of the time GPS is used to try to tame the sheer work rates to do less. Is it working? Yes, but nobody has the magic recipe now. Creating a better model is possible.

Monitoring Procedures: The constraint of football is that practice is very timing-oriented. Unless one is walking through, speed is never going to be 60-75%. The total volume of practice and training and the variability are more important than high velocities. The goals are twofold: finding a weekly setup that allows position coaches to get on the same page and leave some energy in the bank for strength coaches for lifting, and providing a more precise weekly setup than simply minutes of work.

Quick Tip: Create models for Team and Positional coaches of what can be done to save energy for the weight room and make planned rest smarter.


Sleep Monitoring Guidelines

Sleep monitoring is hot right now, but people need to cool off. Without athlete buy-in, infographics and guest lectures from sleep science researchers don’t result in improvements. Most athletes know you can fly with the eagles during the day if you run with the turkeys at night. The hard issue is getting data of what they are doing as well as the details of sleeping over time. Athletes are willing to train harder, but sacrificing time or the social and romantic fun of the evening is hard.

Currently, coaches want to get an idea on sleep devices so they can budget an enterprise option. Think about this for a minute. Sleep data involves 365 nights, and coaches have to get sub-metrics (duration, quality, and chronicity details) with entire rosters. The daily grind of simply managing sleep and follow-up questions makes even the theoretical idea of handling sleep a big task. Many teams claim they are getting sleep data. But just ask them if they have a team report beyond subjective responses, and usually those pundits are quiet.

Monitoring Procedures: The data points should focus on where the athlete is sleeping, the rhythm of waking and sleep times, the duration in bed, the duration of sleep, and its quality. Don’t bother creating sleep scores versus just the raw data. Share annual data for perspective so the 2-week “flash study” is exposed as nothing more than a stunt.

Quick Tip: It’s better to focus on consistency and sustainability over the season versus data mining one sleep session with athletes.

Regeneration Topics and Protocols


Using Ice or Ice Baths

Ice baths (cold water immersion, or CWI) and icing after competition or training have attracted a lot of attention in recent years, even though both appear to retard the regeneration of the body. Even their medical use after trauma is being scrutinized—for good reason, as some research shows cellular impairment in remodeling.

Professional Soccer Athlete in Ice Bath

Figure 4. Professional soccer player Jamie Rodriguez attempting to recover in a tub of unknown temperature. Cold water immersion isn’t usually a good option for athletes.

So why does professional sport continue to ice and hop in the cold tub? Cold therapy or icing doesn’t fix anything though they create an analgesic-like response without the risks of some medications. Nobody with a college degree in sport science thinks muscles grow faster from cold; it’s just that they feel better after being beat up. With the frequency of training sometimes too high, the muting of the stimulus isn’t going to matter if the sessions are timed properly. Still, having people doing cold after practices raises questions of whether the training is appropriate. Even after injuries I focus more on lymphatic pumping and other options than icing, but some research shows possible benefits of cryotherapy on heavy trauma.

Some HRV research asks if CWI and the perception of feeling better may be good for tournaments and heavy competition schedules, but I think morning sessions are fine in-season. I have done biopsy work and all being equal, see no advantages to those who remove cold therapy from their routines. Most studies simply don’t replicate a multi-session program.

Regeneration Protocol: The only time ice makes sense occurs when the world of professional sport moves toward walking wounded. I still find pool sessions to be more valuable, and if one is injured or competing short, one needs to move from managing to medical interventions. CWI can be done the following morning before a warm-up, as the timing doesn’t influence the biological adaptation muting that some people fear. I suggest reading The Science of Running by Steve Magness to understand the theoretical model of periodizing recovery strategies.

Quick Tip: Cold may help modern athletes cope with symptoms after competition, but time it better by choosing morning applications rather than acutely after training sessions. Higher frequency training doesn’t seem to be as affected, so evaluate your program to see if interference is truly a problem.


Sauna Sessions and Recovery

Heat is gaining interest from teams attempting to hack the plasma volume benefits and HRV changes from sauna work. Some teams train in the heat and purposely try to dehydrate players to get their bodies to increase plasma volume acutely and maintain this regimen over a season. Instead of driving up hemoglobin, they are attempting to increase the speed (viscosity change) to deliver the same amount of red blood cells (and hemoglobin). Research on acute plasma volume expansion (APVE) shows some positive changes [1], but the theory isn’t showing real VO2 kinetic boosting. I have looked at 27 papers, and the study construction and subjects tested lead me to think we still don’t know why athletes improve from various endurance protocols.

Some recent cycling studies point to passive heat as an avenue, but the research is still early. A heat acclimatization study (2) on cycling showed no performance boost, but the question is, does additional heat change things versus replacing training in hot conditions? Sometimes the change doesn’t outweigh the compromised training.

The truth may be similar to altitude studies showing that some athletes don’t respond well, or at all. Some even get worse. Many heat-training advocates think some athletes improve oxygen transfer from plasma volume. That may happen, but if the workouts are not driving aerobic adaptations (hemoglobin mass), they’re likely creating a tradeoff and not an improvement.

I have found athletes with higher hematocrit levels respond to passive heat options if plasma volume increases and the workouts at regular temperatures are solid. Many athletes like being in a sauna. Sitting there for 30 minutes a few times a week is realistic and can in theory increase performance. Microcirculation studies from heat show no capillary density changes, so I believe the boosting is only for large athletes struggling to achieve core fitness.

Regeneration Protocol: Based on the cycling study with Buchheit (3), the temperature and duration aren’t extreme. Some caution is suggested, as the use of saunas is not for everyone. The solution is following the protocols of 2–3 sessions of sauna bathing and HRV monitoring and looking for positive trends as well as decreases in hematocrit. The effectiveness of this option is still unknown and it could be a glorified placebo. But the time trials I have seen share a performance benefit, so further investigation is suggested.

Quick Tip: Plasma volume expansion may help with some athletes, especially if they have higher hematocrit values and are less trained, but how this works is still a mystery and if it works as believed is still unknown.


Compression and Travel

What is the impact of compression garments on travel fatigue? I wrote a review here, and I still don’t think much room exists for compression in sport besides comfort. The question is, how does one look at the entire continuum of compression options while traveling? The research isn’t there. But I believe that the longer the flight, the creation of fatigue becomes more than just crossing multiple time zones. Some believe that hydration issues exist, others focus on sitting for prolonged periods, and still others like myself believe swelling of the lower limbs may be reduced by a body garment. Some NBA teams have been rumored to use NormaTec while in flight, but this is speculation.

I have done biochemical and physiological testing before and after flights longer than 2 hours and yes, the body responds poorly. The intervention is largely what you do before and after the flight since not much can be done besides getting up and walking around. One option is looking at thermotherapy or pool sessions following evening arrivals, but the logistics are a big juggle. Light workouts simply are not going to happen with 3:00 AM arrivals, so most of the chances to mend the gap are few.

Regeneration Protocol: The best option when one lands is a combination of food, managing swelling, and priming the body for sleep. I prefer a combination of exercise and lymphatic kinetics to stimulate the appetite and move the body. Passive options are okay, and electrical muscle stimulation (EMS) can be done on the plane. Thirty minutes of light aerobic pool activity in the pool does make a change (laser perimeter) and improves HRV and the testosterone:cortisol ratio. A normal meal at the appropriate time is helpful, but sleeping right after eating may create digestive issues.

Quick Tip: Compression garments are for comfort and travel, not performance or recovery. Focus on the routines of travel before heading on the plane and right after with a plan.


EMS Practical Considerations

Why team sports don’t equip athletes with personal EMS units is a mystery to me. It’s the most efficient way to deal with injury patterns when training is limited. A great video can be found here. The amount of lymphatic pumping is weak compared to pool training, though if a limb is banged up some free proteins moving through the system are moving the chains. Research on lymphatic pumping is small, and teams should look at the soccer studies to take advantage of the complementary strength benefits.

Personal EMS Unit

Figure 5. Personal EMS units will evolve to include more sensors and connectivity to coaches.

The recovery of strength is not true recovery, but what we want with regeneration techniques is the facilitation of improved states of performance, not just a “sushi menu” of modalities to do à la carte. Collision sports like rugby and American football need EMS, due to the increased trauma the athletes experience. As the technology improves, expect the development of a way to capture sessions of EMS treatment variables and track athlete compliance via the Cloud.

Video 1. Why team sports don’t equip athletes with personal EMS units is a mystery to me. It’s the most efficient way to deal with injury patterns when training is limited.

Regeneration Protocol: The times when training is compromised are when EMS should be done. Be sure to schedule enough options for athletes to do EMS. It’s important to see when it should be done for athletes who find it weird or uncomfortable. Athletes, even compliant ones, may find EMS to be a burden, so it’s better to cycle it some of the time rather than have an athlete burnout and do it again later.

Quick Tip: EMS is great for team sport for strength and travel, but it’s not going to do as much as a simple 20-minute pool workout. When looking for recovery look for pools as the lymphatic kinetics is far higher, and you get other secondary benefits.


Low Carbohydrate and Hydration Phases

Some coaches are experimenting with low-carbohydrate training to deepen adaptations, and now believe that staying dehydrated during training will have the same effect. So far no research shows this to be a game changer, though if someone has something better than a “nothing placebo” I will change my mind. Theoretical changes to the body include better fuel utilization and mitochondrial biogenesis, but the best indicator is a body that moves faster and farther, not small sampled biological adaptations. Tradeoffs happen all the time, and some benefits become a loss when overall performance has changed. For example, many athletes lift to get stronger. But when muscle mass increases more than the power-to-weight ratio, it may not help.

Similar to training in the heat, training with lower hydration levels is a poor idea for two real-world reasons. First, even if the science is ahead of the curve, the legal acceptance of something going wrong is not. Second, blood plasma expansion is still unknown and may not be worth compromising training with athletes who already have nearly maximized their plasma volume. It’s better to have good workouts with less room for improvement than bad workouts with room to improve.

Regeneration Protocol: A wise approach is having the right fueling and hydration plan, not one that attempts to fool the body or hack it. I like removing artificial dietary practices during the offseason and early GPP to maximize internal adaptations and capacities, but not challenge recovery. Challenge the effort and output in training, not take away resources. No sleep research I know of shows benefits from not getting enough rest, and the point is that it’s better to leave things alone and focus on good training rather than hacking the body. Challenge the body by going harder and driving adaptations, not making things harder and having compromised workouts.

Quick Tip: Restricted Hydration and Low Carbohydrate ideas have very little benefit to athletes as the tradeoffs are not worth it. When in doubt moderation seems to work better than extremism.

Please share so others may benefit.



[1] Berger N, Campbell I, Wilkerson I, Jones A. (2006) “Influence of acute plasma volume expansion on VO kinetics, VO2 peak, and performance during high-intensity cycle exercise.” J Appl Physiol 101: 707–714.

[2] Karlsen A, Racinais S, Jensen MV, Nørgaard SJ, Bonne T, Nybo L. (2015) “Heat acclimatization does not improve VO2 max or cycling performance in a cool climate in trained cyclists.” Scand J Med Sci Sports. 25 Suppl 1: 269–276.

[3] Stanley J, Halliday A, D’Auria S, Buchheit M, Leicht AS. (2015 ) “Effect of sauna-based heat acclimation on plasma volume and heart rate variability.” Eur J Appl Physiol. Apr;115(4): 785–794.

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