In part 1 of this series I made the dreadful admission that I am not a fan of Maximal Aerobic Speed (MAS) training. In this second instalment of the series I’ll give you reasons 6 to 9 of my list. Feel free to chime in with your thoughts about this training topic below.
6. I think MAS may be the wrong map
One of the big lessons I have taken this year from reading Nassim Taleb is that we humans love to cling to information and evidence to support our beliefs. Sometimes we even see patterns and links where there aren’t any in reality. It is much more comforting to cling to something rather than nothing in the face of extremely complex topics that we don’t fully understand. To paraphrase Taleb:
Most people prefer a map of the Pyrenees when they are lost in the Alps than no map at all
Let’s remind ourselves now of the general consensus goal of an energy system or work capacity training model for field based sports (stolen from Mladen Jovanovic): maximal efforts performed with the greatest intensity, frequency and sustainability possible. Now I invite you to take a stroll through the literature on maximal aerobic speed running…
I’ve had a thorough look at the available literature on MAS based research or training interventions and so far I can establish a few different things:
- It is positively correlated with VO2 max
- It is positively correlated by number of high intensity metres
- It makes your MAS go up when you test it with a time trial or 30:15 IFT
In response to number 1 and 2, I would say “big deal”. VO2 max is not all it is cracked up to be- there are other stronger correlates for endurance performance- and it is largely fixed genetically speaking. For number 3: correlation does not imply causation. We should expect fitter players to cover more high intensity metres.
The question is, does MAS optimally prepare athletes to cover MORE high intensity metres, and do so more often? I have yet to see a study that confirms this is the case. If MAS even the right expression of an athlete’s work capacity to play their sport when no aspect of it is maximal in nature?
My hunch is no. We just cling to it because it is one number, because we can make it go up with training, and because we can pump out pretty spreadsheets using testing data. MAS is a map of the Pyrenees when we are lost in the Alps.
7. MAS isn’t the puzzle, it is just a piece of the puzzle
As happens with many training topics, MAS has been embraced by strength and conditioning community to the point where I feel it’s importance has been overstated (joining Olympic lifting, high intensity conditioning, the functional movement screen, data management, and many other items).
As such I feel many coaches are content to reduce solving the problem of energy system development/work capacity to running a time trial test or 30:15 IFT, popping the numbers in a spreadsheet, then running MAS grids for a few months. If you are a coach with limited time or resources, I understand. If however you are in the professional ranks (or aspire to be), I think we are doing our athletes a disservice if we do not go a level deeper.
Off the top of my head here are some of the things that can be a limiting factor in work capacity (some more than others obviously):
- Breathing musculature and respiratory mechanics
- Eccentric and concentric cardiac hypertrophy
- Ability of the body to redistribute blood to active tissues
- Mitochondrial number and density
- Aerobic enzyme number
- Blood volume
- Slow twitch fibre hypertrophy
- Lactate buffering
- Central psychological resistance to fatigue
- Central physiological resistance to fatigue
- Maximal force production capacity
- Movement strategies
- Movement economy
That is a LONG list of things that may need our attention. It is logical that although there will be common themes, we as coaches will be faced by many different athletes, with many different needs. Each may need a slightly different approach to address the weak link within their respective chain.
To me it is illogical that we can expect MAS to be an optimal solution to solve all of these limiting factors. It would be like only utilising heavy strength training to increase force production on the field of play (a common error). I am not saying every player is a unique little snowflake who needs an individually tailored programme, but I think we need a range of solutions in place, not just one. MAS is just one tool, not THE tool.
8. Different athletes, yet same programme
I’ve already written this year that I have become more and more aware of the need for testing data to not just establish what an athlete’s score is, but more importantly how or why they scored a particular way. In doing so we are able to better understand an athlete’s weaknesses, then address them with focussed programming.
Energy system development is no different in this regard. Ben Peterson exposed me to this way back in 2012 when discussing his PhD work at CVASPS: the idea that two athletes may score identically on an endurance test but do so in markedly different ways. Ben talked about “aerobic base” athletes and “anaerobic capacity” athletes.
Aerobic athletes are those who only exceed their lactate threshold towards the end of the test. Once they start working anaerobically, it gets ugly very fast. The anaerobic athletes on the other hand may break LT very early on in the test, but handle this environment a lot better. Two very different types of athletes, with different types of needs, yet a MAS based programme may prescribe them the exact same programme.
And types of athletes may not just be limited to anaerobic vs. anaerobic. We may be exposed to sloppy vs. clean movers, peripherally fit athletes vs. centrally fit athletes, smart movement strategists and poor movement strategists. Again, I am not suggesting a million different programmes, but one is definitely too few. Likewise we need to avoid relying only on tests which do not allow us to understand the “why” behind the “what”.
9. Mixed signalling for adaptation
Obviously a huge part of what we train for in work capacity is physiological adaptation. This is because a huge chunk of the information the CNS uses to make a decision about whether or not to fatigue is derived from the internal physiological environment. If we can reduce physiological signals of fatigue, we can work harder for longer.
We must set in motion a chain of events that culminate in certain physiological adaptations (which hopefully we have identified as likely limiting factors in our athletes). The events are as follows:
- Perform work
- Create a change in the internal physiological environment
- Trigger intracellular signalling
- Activate gene pathways
The more consistent a physiological environment we create, the stronger the signal we create, the more adaptation we trigger. The more varied the environment, the weaker the signal, the more thinly we spread our adaptation resources and the less we are able to adapt in one specific fashion. This is the price of inaccuracy and it worsens with training age, as the threshold of adaptation gets ever higher.
Now let’s think about a MAS style session of 15s of work at 110% of MAS, followed by 15s of passive rest, repeated for 10 reps, for two blocks separated by a 5 minute rest period. What would heart rate look like during the first few reps compared to the last? What about blood lactate concentrations? What about inorganic phosphate?
Whatever physiological variable we are looking at I think it is fair to say that the internal environment we are creating with MAS intervals is not a consistent one. As such I think we are creating quite a mixed signal for adaptation, and adapting less in one particular direction than we could be. There are obvious counter arguments to this point:
1. With MAS we are also developing movement economy and mental toughness. However I think there are more efficient ways to do so.
2. The intensity of MAS intervals from a mechanical perspective is highly consistent (all reps performed at X% of MAS). However I would counter that physiologically this is not the case, and when we are trying to create physiological adaptation this should take precedence over mechanical power.
In summary, once again I feel that maximal aerobic speed may be an appropriate energy system development tool for coaches who are limited in terms of resources. At best, though maximal aerobic speed clearly improves with training, I feel the MAS model is incomplete and inaccurate representation of energy system demands for field based sports and how to solve that problem. At worst I feel it may actually serve to blunt adaptation and detract from the development of the physical abilities that truly distinguish elite athletes from average ones, namely maximal outputs.