Introduction
I’m currently undergoing the EXOS Performance Specialist certification. In the Exos system, a concurrent approach to training is chosen. I recall Mike Boyle saying in some Episode of the strength coach podcast that his athletes always do concurrent training in hence they always train for speed and strength and condition as well. Now whether or not you agree with Mike’s views on bilateral training or certain aspects of the EXOS system, results speak for themselves.
On the other hand, you have proponents of more focused periodization schemes that allow for a greater development of individual biomotor qualities. For example, Joel Jamison propagates a block periodization model in his excellent book „Ultimate MMA Conditioning“ [JAMI2009]. Joel trains, amongst others, Demetrius „Mighty Mouse“ Johnson, so again, success leaves clues as they say.
It’s really hard to say which periodization model works better/best for a variety of reasons. My last posts summarize some state of the art regarding undulating and daily undulating periodization (or rather, programming). In this post I will discuss concurrent training in the context of martial arts, its strengths, weaknesses and how we implement it at my gym.
Concurrent vs. Non-Concurrent Training
Before diving deeper into the topic, it’s important to have a working definition for the term „concurrent training“. All it really says is that multiple biomotor abilities are trained within the same training block or possibly even the same session. While this concept may intuitively make sense, certain strings are attached. Critics of this method argue that different biomotor abilities directly compete with each other in terms of physiological adaptation and hence, cannot be developed simultaneously. Consider the case of energy system training – aerobic and anaerobic training result in vastly different adaptations. Mike Robertson [ROBE2014] wrote an excellent post on the matter, in which he states that
- Aerobic training develops aerobic enzymes. Anaerobic training develops anaerobic enzymes.
- Aerobic training builds mitochondria. Anaerobic training destroys mitochondria.
- Aerobic training stimulates the parasympathetic (rest-and-digest) nervous system. Anaerobic training stimulates the sympathetic (fight-or-flight) nervous system.
So apparently, from a physiological point of view, interferences between different training methods need to be considered. Different biomotor abilities can also have synergistic effects when trained in conjunction. Maximum strength, together with speed training or plyometrics, can lead to improved performance due to a phenomenon called PAP (post activation potential). These transferences can be taken advantage of.
Another criticism of concurrent training regards training volume. At a certain level, an athlete needs to invest a serious amount of time and energy when trying to develop a certain biomotor ability. For example, take a marathon runner. Strength training, agility training and a plyometrics program might be desirable from a holistic point of view, but at the end of the day, each requires time, increased regeneration times and potentially an increased risk of injury. Therefore, it will take away from the time that can be spent on running. In order to increase a biomotor ability, the training stimulus must exceed a certain threshold. For a beginner, this threshold will be relatively low and hence, one or two weekly sessions at a low volume might indeed result in an improved aerobic capacity. For a seasoned runner, on the other hand, a large training volume is required in order to elicit even a slight improvement. The same holds true for strength training. While a beginner may double his muscular strength in the first year of training ( this is actually known as „beginner gains“), powerlifters might have to work for an entire year for a single-digit percent improvement. This is one of the main factors that Issurin [ISSU2008] mentions in his works.
In defense of concurrent training
Fighters, however, are not necessarily strong, fast or enduring enough to warrant such high training volumes for any single biomotor ability. Although fighters are great allrounders, we don’t really excel at anything. In their book „Easy Strength“ [JOTS2011], Dan John and Pavel Tsatsouline characterize combat athletes as quadrant 3 athletes. This means that fighters need to develop „few qualities at a low or moderate level of relative max“. I tend to agree with that assessment. From an athletic point of view, fighters are beginners or at the very best, intermediates in their physical development. This is not meant in any derogatory manner. It’s just that fighters have to spend a tremendous amount of time learning, drilling and refining techniques. We’re also (sadly) injured a lot, which results in rather frequent interruptions of the training process. For those reasons, fighters can make gains at much lower volumes than (olympic level) athletes of more specialized, less technical sports.
In our sport, there’s no real on- and off-season, so a practical periodization model does not come as naturally as in other, more season-dependent sports. Fights are often taken on short notice, event dates may change during prep (happened to me) or scheduled fighters might be replaced in the last minute. This is a common theme and one of the things that led Mladen to develop his theories on flexible periodization. A fighter that is too far away from his peak (or weight, for that matter), can’t take anything on short notice and hope to win. That’s a major downside of a block model – imagine you’re in an aerobic base block and you get the offer to fight for a title in three weeks. You haven’t been training speed, strength and power for the last two months. Under these circumstances, you’re probably well developed with regards to aerobic fitness, but maybe rather weak and slow. Developing your lactic system ultra-short term will pose a serious challenge as well. While a lot can be done in six weeks, three weeks might not give you enough time to sufficiently prepare.
Research has consistently shown that periodized programs outperform non-periodized programs in terms of performance enhancement. Which periodization model (if any) reigns superior over the others has been debated for the last couple of decades, though, and so far, no conclusion has been reached. Something that Mladen said changed my personal outlook on the matter rather substantially. You see, I was raised in a family of technicians. My father is an engineer. I went to technical university and recently finished my masters degree. All of this shaped me into a rather rational person. I like to think in a very structured way and work with clear cut systems. When it comes to periodization, I’d like to have a system which, once set up, runs smoothly and produces optimal results. Trouble is, rigid systems tend to be fragile and suffer from unforeseen events. Refer to Nassim Talebs work for more information on the topic. Anti fragile systems, on the other hand, gain from and improve through unforeseen events and a certain degree of disorder. Coming back to Mladen – he posed the question whether maybe, the single factor that differentiates periodized from noon-periodized training was the variation of the training stimulus. After doing some research, I found that John Kiely raised this issue in his work [KIE2017]. In the article, Kiely concludes that
Selye’s paradigm contained many partial truths, but its partial validity should not obscure its critical omissions. As we approach the third decade of the twenty-first century, the disconnect between periodization doctrine and both academic insight and progressive coaching practice continues to grow
The thought that variation may be the true factor that drives all periodization models still intrigues me. Think about it. What’s the one common aspect between all periodization models? It’s the variation of the training stimulus. Studies [MIR+2011, PRE+2009, RHE+2002] show that daily undulating periodization seems more effective than linear periodization. Maybe that’s due to the higher degree of variation. Coach Dos implements his alternating linear model, which increases variation by alternating – as the name implies – between more hypertrophy oriented loading blocks on one hand and maximum strength blocks on the other hand. The Westside Barbell Club is home to some of the strongest power lifters in the world (all drug issues aside). Their system? Variation, taken to the extreme in every regard. Bar speed, relative intensity and exercise selection are constantly changed in the conjugate system.
Of course, it’s worth noting that power lifters are single factor athletes in that they need only one quality, namely maximal strength, developed to the highest degree possible. Speed, agility, power endurance and aerobic capacity aren’t really relevant to them. This is a crucial consideration and mixed sports athletes need to posses a much wider spectrum of biomotor abilities.
It goes without saying, that variation can be overdone, to a point where it results in chaos. The NSCA’s standpoint [HOFF2012] is that0
Although variation of training factors is a central component of an appropriately designed training plan, random or excessive variation should be avoided, since performance gains will be muted.
It seems that having a framework and implementing variation within the boundaries of that framework is likely to yield the best results. Going back to Westside Barbell again, the conjugate system implemented by Simmons revolves around dynamic effort and max effort days. Aerobic conditioning or lactic capacity circuits are outside of the scope of that framework and would likely interfere with the strength adaptations.
Related Work
In the following Sections, I will briefly present and then discuss some work related to the topic of concurrent training.
Strength & Power vs Endurance
Different endurance training methods seem to exhibit varying degrees of compatibility with strength and power training. Intuitively, it makes sense that high-power methods such as sprint intervals or kettlebell work, e.g., in the form of explosive repeat intervals, would work better in conjunction with speed and power training than low intensity activities such as low intensity steady stafe (LISS) road work.
Tack [TACK2013] states that
HIIT is important as a substitute for long slow endurance training, which may have a negative effect on strength and power development
Rhea et. al. performed a study on college level baseball players, comparing strength training to concurrent training. Power output in the lower body went down for the group that performed moderate- to high intensity continuous endurance training (jogging or cycling at 12-18 Borg for 20-60 minutes, 3-4 times weekly), as opposed to the sprint training group, who did nothing but HIIT for energy system training. The authors conclude that
This research demonstrates that power training and intense, lengthy cardiovascular endurance training are not compatible with the aerobic training resulting in decreased power among college baseball players
The study was – as usual – based on a very small sample size. This somewhat limits its impact. Furthermore, sprint intervals have been shown to be a viable method of improving VO2Max and/or aerobic capacity [AST+2012, BUR+2008,FOS+2015, GIB+2006, GIS+2014, HAZ+2010, MAC+2011, SLO+2013]. Hence, both groups performed concurrent training in that both strength and endurance were trained. Unfortunately, data on VO2Max pre- and post-intervention wasn’t included in the paper. Baseball is a very power-oriented sport which doesn’t call for intermediate efforts. Short busts of activity are interspersed by rather long periods of very low intensity activities, i.e., standing or walking. It makes sense in such a scenario to train the aerobic system to resupply the ATP-CP system to sustain repeated sprint ability. Strong First calls this aerobic-alactic conditioning. Eric Oetter [OETT2011] wrote a piece on repeated sprint ability and the contributions of the different energy systems.
Cantrell et. al. also investigated the effect of concurrent training on strength adaptations in fourteen recreationally active men. The study design was similar to the work performed by Threes et. al., as was the result:
Preliminary findings suggest that performing concurrent sprint interval and strength training does not attenuate the strength response when compared to ST alone, while also improves aerobic performance measures, such as VO2max at the same time.
Of course, the small sample size seriously impairs the studies validity. Also, strength training and energy system training were performed on separate days.
Aerobic vs. Anaerobic Development
Astorino st al [AST+2012] investigate the effect of short-term HIIT interventions on VO2Max and, although data conflicts with the work performed by Burgomaster [BUR+2005] and Gibala [GIB+2006], the authors conclude that
Data reveal that short-term HIIT improves _VO2max, power output, and O2 pulse in active men and women, although it is unknown if sustained HIIT would continue to induce these adaptations in the long term
Hazell et al., who investigated the effect of 10- and 30-second all out bike sprint intervals on aerobic and anaerobic performance found that
…10-s (with either 2 or 4 min recovery) and 30-s SIT bouts are effective for increasing anaerobic and aerobic performance.
Of course, there is also the (in)famous Tabata study which states that
…adequate highintensity intermitte nt training may improve both anaerobic and aerobic energy supplying systems significantly, probably through imposing intensive stimuli on both systems
Other studies [GIGI2013, SMI+2013, TAL+2007, ZIE+2011] also found favorable effects of HIIT on VO2Max, fat oxidation capacity and other markers traditionally associated to the aerobic system.
Interpretation
In conclusion, sprint intervals seem to go well with strength training in a concurrent program. Martin Rooney makes extensive use of these in his Training For Warriors (http://www.trainingforwarriors.com) system. Explosive repeats probably fit into the same category in that regard. On the Robertson Training Systems Podcast (http://robertsontrainingsystems.com/blog/category/podcast/), Robbie Bourke states that he loves explosive repeats as a means of developing the aerobic base. I couldn’t agree more, especially in a sport such as fighting, which inherently requires the athlete to be able to repeat explosive efforts.
The matter of aerobic vs anaerobic adaptations seems to be less clear cut. While some authors argue against the concurrent development of these two energy systems, (most notably Joel Jamieson), the studies presented in the related work indicate that a concurrent development is possible, under certain conditions. James et al. propose a periodization model for MMA fighters. After reviewing the literature, the conclude that
…These findings suggest that despite conflicting mechanisms underpinning the adaptations to various MMA training modalities, it is feasible to develop strength, power, and endurance concurrently in athletes. However, poorly organizing these modalities will limit performance gains.
A distinction needs to be made between central and peripheral adaptations [LEV+1999]. Maybe, the central adaptations (increased stroke volume, running efficiency, etc.) don’t blunt strength adaptations as much as peripheral ones (aerobic enzyme formation, fiber shift toward ST fibers, etc.). Local muscular endurace adaptations are driven by a certain time under tension (or hypoxic conditions in the muscle cell), after which the accumulation of hydrogen ions and subsequently, the buffering via lactic acid occurs. Short bursts of intensity (such as 10 sec all out bike sprint or a 15m sprint or the kettlebell protocol suggested by Falatic et al.[FAL+2015]) may not elicit this reaction, as they are primarily fuelled by the ATP-CP system and hence, don’t induce the same local adaptations as longer work intervals. This needs to be considered when designing a concurrent training regime.
Also, the necessary minimal effective dose needs to be taken into account for any given training stimulus. Developing aerobic capactiy for an endurance athlete, e.g., a long distance runner, will take a significantly higher amount of training volume than with a combat athlete. As mentioned, the fact that olympic level athletes from specialized sports need tremendous workloads in order to improve a given biomotor ability was one of the main points that led Issurin to develop his block periodization model. A combat athlete, especially on an amateur or even semi-pro level might not require the same degree of specialization.
Making it work
Recently, while talking shop with my good friends Marc (who runs his fantastic gym, Yu-Performance here in Vienna) and Ben (who is currently working as a scientific assistant at the Vienna University of Sports, where he’s researching the applications of velocity based strength training), I realized something that has so far not crossed my mind. Namely, it occurred to me that one of my biggest weaknesses may very well be my strongest suit at the same time. In a podcast, Rob Pilger stated that he’s a holistic coach. It’s pretty much the same with me, really. I don’t work with a team of nutritionists, skill coaches, mental coaches, exercise physiologists and S&C coaches. I’m all of that and more. The one thing I outsource (to the largest degree) is the physical therapy part. I’m more than happy to put that into Anna’s competent hands. Anna is my assistant instructor, so she knows exactly how I train my fighters and what I expect them to be capable of doing. Check out her blog at wiederanders.blogspot.co.at.
I might not be the best striking coach out there. My grappling skills are far from where I want them to be. Compared to Marc, my knowledge on physiology and its application in nutrition is rather limited (although I definitely know a lot more than your average run of the mill trainer). Ben probably dismissed more training methods and scientific details on strength training than I ever learned. Still, my skills I all of these areas (and then some more) is apparently sufficient to train fighters at a high level. Last year, my team, despite being small, took home around ten national titles in kickboxing and quite a few international medals in Taekwondo. Having everything in one place when it comes to planning the training process has tremendous merits.
I know exactly what everyone’s doing during skill practice, sparring and S&C sessions. Speaking of which, we implement two weekly S&C sessions. During each class, we’d perform low-volume plyometrics, EXOS style, and then progress to lifting, primarily unilateral stuff. At the end, we condition. I’ve covered our S&C model and its evolution in great detail over the course of the last years, so I won’t bother at this point. I was pleasantly surprised that the guys over at fight camp conditioning follow a template that looks pretty much like ours.
At my gym, we follow the credo of „integrate, don’t isolate“. This means that around half of the EST is done in a sport-specific manner or at least, as part of technical practice. During aerobic blocks, this could mean intermittent core training, which basically alternates between bouts of rope skipping and core stability exercises. To support this, we’d simultaneously implement cardiac output training with e.g., kettlebell swings, as described in one of my earlier posts. Glycolitic training is usually kept to the last four to six weeks pre-fight. My go-to method is lactic explosive repeat.
During that time, strength isn’t developed but rather maintained. As the event comes closer, we gradually taper down the volume and rate of perceived exertion (at constant intensity). The exception here are time periods when there’s nothing on the horizon for say, three months or longer. In such a scenario, I’d schedule a short glycolitic block of three to four weeks. This makes it easier for my athletes to go through the inevitable next block, as they grow accustomed to the methods. Sparring is inherently glycolitic in nature. Hence, we’re incorporating at least one anaerobic session every week anyway.
I chose a daily undulating periodization model for our strength work. This is due to various reasons, most of which I have already elaborated on in previous posts. An important aspect I haven’t discussed in detail is the coordination with the specific training. We have two weekly S&C sessions, on Tuesday and Saturday. On Tuesday, the session is preceded by one hour of very light technical work. Saturday, on the other hand, is our heavy sparring day. Keeping this in mind, I designated the first strength session of the week as the heavy day, i.e., mostly in the 4-6 RM range. On that day, intramuscular coordination and neurological strength are the primary focus. The weeks second session is set in a higher repetition range, something along the lines of 8-12. On that day, we’re after a stimulus that is more metabolic in nature. The plyometrics are performed during the sparring session in that day, of course. Also, I put them into every specific session. Not a ton, mind you. Something like three sets of four to six reps would be typical. I basically follow the EXOS guidelines of two to three movements at one or two sets of four to six repetitions. Over the course of the week, that still accumulates to something along the lines of twelve sets. While a concentrated plyometric block of six weeks will yield more impressive results with regards to speed-strength development, micro-dosing keeps my athletes fast, powerful and explosive at any point in time. Little and often over the long haul, as Dan John puts it.
Our weekly schedule looks as follows:
| Day | Content | Intensity | Focus |
| Mo | 75 Minutes of striking (including a glycolitic block, if applicable) | low / high (if glycolitic training is performed) | plyos, technique & partner drills |
| 75 minutes of grappling | moderate – high | technique & sparring | |
| Tue | 60 Minutes of striking | low | agility, technique |
| 90 minutes of S&C | high | plyos, neuromuscular efficiency | |
| Thu | 90 Minutes of striking (including a glycolitic block, if applicable) | low / high (if glycolitic training is performed) | plyos, technique & partner drills, EST |
| Sat | 90 minutes of Stand-up sparring | moderate / high, depending on time until the next event | plyos, tactics and specific conditioning |
| 90 minutes of S&C | moderate | hypertrophy / strength endurance |
Note that I’m not necessarily happy with that schedule. Of course, I’d prefer to have all my S&C sessions as stand-alone sessions, or at least not in combination with a sparring. Practicality beats optimality, however, and thus far, I haven’t found a better solution (I am renting my location on four nights per week and for various reasons, can’t get more days ATM).
That’s the beauty of an integrated approach. I can take all aspects into consideration. No running my athletes into the ground a day before a neurologically demanding session is planned. No slow, sore and tired athletes in the weeks most important sparring session. Each session is a piece of the puzzle, in the context of a bigger picture.
This post was a lengthy one and I really don’t consider it finished, but I wanted to share my thoughts ASAP because this was really keeping me busy. In any case, I’d love to read on your thoughts on periodization and how you structure training with your fighters, so feel free to share your thoughts (or links to your stuff) in the comments. Let’s have a discussion.
So long,
don’t get hurt
References
[AST+2012] Astorino, T. A., Allen, R. P., Roberson, D. W., & Jurancich, M. (2012). Effect of high-intensity interval training on cardiovascular function, VO2max, and muscular force. The Journal of Strength & Conditioning Research, 26(1), 138-145.
[BUR+2005] Burgomaster, K. A., Hughes, S. C., Heigenhauser, G. J., Bradwell, S. N., & Gibala, M. J. (2005). Six sessions of sprint interval training increases muscle oxidative potential and cycle endurance capacity in humans. Journal of applied physiology, 98(6), 1985-1990.
[BUR+2008] Burgomaster, K. A., Howarth, K. R., Phillips, S. M., Rakobowchuk, M., MacDonald, M. J., McGee, S. L., & Gibala, M. J. (2008). Similar metabolic adaptations during exercise after low volume sprint interval and traditional endurance training in humans. The Journal of physiology, 586(1), 151-160.
[CAN+2014] Cantrell, G. S., Schilling, B. K., Paquette, M. R., & Murlasits, Z. (2014). Maximal strength, power, and aerobic endurance adaptations to concurrent strength and sprint interval training. European journal of applied physiology, 114(4), 763-771.
[FAL+2015] Falatic, J. A., Plato, P. A., Holder, C., Finch, D., Han, K., & Cisar, C. J. (2015). Effects of kettlebell training on aerobic capacity. The Journal of Strength & Conditioning Research, 29(7), 1943-1947.
[FOS+2015] Foster, C., Farland, C. V., Guidotti, F., Harbin, M., Roberts, B., Schuette, J., … & Porcari, J. P. (2015). The effects of high intensity interval training vs steady state training on aerobic and anaerobic capacity. Journal of sports science & medicine, 14(4), 747.
[GIB+2006] Gibala, M. J., Little, J. P., Van Essen, M., Wilkin, G. P., Burgomaster, K. A., Safdar, A., … & Tarnopolsky, M. A. (2006). Short‐term sprint interval versus traditional endurance training: similar initial adaptations in human skeletal muscle and exercise performance. The Journal of physiology, 575(3), 901-911.
[GIGI2013] Gillen, J. B., & Gibala, M. J. (2013). Is high-intensity interval training a time-efficient exercise strategy to improve health and fitness?. Applied physiology, nutrition, and metabolism, 39(3), 409-412.
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[JOVA2018] Jovanovic, M. (2018), „Why The Concept of Biomotor Abilities is Bullshit“. http://complementarytraining.net/why-the-concept-of-biomotor-abilities-is-bullshit/
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[MIR+2011] Miranda, Fabrício, et al. „Effects of linear vs. daily undulatory periodized resistance training on maximal and submaximal strength gains.“ The Journal of strength & conditioning research 25.7 (2011): 1824-1830.
[OETT2011] Oetter, E. (2011) „Repeated-Sprint Athletes: Energy Systems & Training“. https://www.8weeksout.com/2011/10/10/research-review-energy-systems-interval-training-rsa/
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[RHE+2002] Rhea, Matthew R., et al. „A comparison of linear and daily undulating periodized programs with equated volume and intensity for strength.“ The Journal of strength & conditioning research 16.2 (2002): 250-255
[SMI+2013] Smith, M. M., Sommer, A. J., Starkoff, B. E., & Devor, S. T. (2013). Crossfit-based high-intensity power training improves maximal aerobic fitness and body composition. J Strength Cond Res, 27(11), 3159-3172.
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[ROBE2014] Robertson, M. (2014). „10 Nuggets, Tips and Tricks on Energy System Training“. http://robertsontrainingsystems.com/blog/nuggets-tips-tricks-energy-system-training/
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[SMI+2013] Smith, M. M., Sommer, A. J., Starkoff, B. E., & Devor, S. T. (2013). Crossfit-based high-intensity power training improves maximal aerobic fitness and body composition. J Strength Cond Res, 27(11), 3159-3172.
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[TACK2013] Tack, C. (2013). Evidence-based guidelines for strength and conditioning in mixed martial arts. Strength & Conditioning Journal, 35(5), 79-92.
The Performance Engineer 