Saturday, August 29, 2009
More on athletic balance....
How to use power curves to help determine athletic strengths and weaknesses
One of my key objectives as a coach is to address and rectify the athlete’s weaknesses with respect to the demands of their event.
The first step in addressing is assessing, i.e. determining where the athlete is physiologically weak. I use multiple means in making this assessment, including laboratory testing (which I have written about at length) along with field data, which will be the focus of this article.
One of the key principles within my training philosophy is that of athletic ‘balance’. This is no doubt, at least in part, bred from the testing that I have performed on a wide array of athletes of different events of different duration. In all cases, the general ‘athleticism’ of these athletes shines through, to some extent, irrespective of their specific event.
This is more than just platitude. In the communist GDR for example, all athletes from marathon runners to Olympic lifters to 1500m swimmers, first had to pass a ‘general athleticism test’ in order to be considered for the sports schools that would enable them to eventually practice their specialty. The criteria for a male 13 year old was as follows (Arbeit, 1997):
• Height: 1.71-1.76m
• 30m sprint: 4.0s
• 3x hop: 6.0-6.4m
• Ball throw (165g): 54-60m
• Shot Put (3.0kg): 9.0-9.5m
• 1500m Run: 4:40-4:50
My first personal ‘aha’ moment on the notion of athletic balance came ‘way back when’ during my college days. Our sports science class represented a cross section of elite athletes from a wide variety of sports, ranging from body builders to tennis players to swimmers to distance runners. It is an understatement to say that I was frequently surprised by who ‘topped the charts’ in the various physiological tests. Our body builder had the highest VO2max, a pro skateboarder topped the pull-up test and, just as surprisingly, when we took to the track for running field tests, our elite 10K/marathon runner came in top 3 in running tests of ALL DURATIONS, ranging from a 5K time trial down to a 60m dash!!
This pattern has since been confirmed as I’ve gone about my business as a coach of elite and AG swimmers and triathletes.
World class 1500m swimmers will beat National class 100m ‘specialists’ in a 100m race. Likewise, world class Ironman triathletes have surprisingly high 5sec power numbers, beaten perhaps by equally world class road and track cyclists, but certainly equal to or better than a Cat 2 ‘specialist’ sprinter (incidentally, the use of my inverted commas is an attempt to convey my view that a Cat 2 racer shouldn’t be a ‘specialist’ at anything, but rather should continue to focus on general development, but that is the subject for another blog…)
So, second to my central job of getting my athletes fit enough to train, my next job is to make sure that the training is focused on long term athletic balance, which will eventually lead to the athlete fulfilling their potential in their most genetically appropriate event. Of course, this implies that I have some idea of what ‘ideal’ balance is.
First of all, let’s throw out the epitome of athletic balance by looking at world best powers over each duration (Wilson, 2004):
Of course, despite the importance of balance that I have outlined, we wouldn’t expect a world class Ironman to also have world class anaerobic capacity. While the general shape of the curve will be the same for all athletes, parts of the curve will be warped to favor the athlete’s strengths/primary event. For example, below I have overlayed actual power data from a world class Ironman athlete with that of a similarly world class male road cyclist.
The differences are evident. While both have very strong curve ‘ends’ (in fact their maximal power is separated by less than 100W and their 4hr power by 12W!!), the difference in the middle of the curve is obvious. The anaerobic capacity of the road cyclist shines through in a significantly higher curve in the 1-20min time frames. This is the result of an athlete with very good basic strength and endurance specifically preparing for the decisive demands of their event.
On the flip-side, while not as obvious on this curve, as the duration increases, a trend is evident, the Ironman athlete loses very little power, while the road cyclists curve is on a steeper descent. Again, the result of an athlete with very high levels of strength and endurance (at least to the 4hr mark), developing the economy and lipolytic capacity to prepare specifically for the demands of their event.
If you look at the curves above, you will notice that beyond the 10 minute mark, the curve drops at a pretty steady rate (with the exception of the 30 minute point for road cyclists which falls within the range of TT performance and is therefore typically stronger than the other points). Beyond 10mins, the curve drops in a pretty linear fashion. Practically, then, the ‘steepness’ of this descent can be quantitatively defined. In fact, several coaches have developed rules of thumb that assess an athlete’s endurance via their fatigue rate. You may be familiar with Jack Daniels 2.2+10s rule, which implies a fatigue rate of 10% as the distance doubles. Joe Friel suggests a fatigue rate of 5% as the duration doubles in the Triathlete’s Training Bible, while George Dallam introduces a similar concept by looking at individual fatigue curves in Championship Triathlon Training. Based on the numbers that I have seen, here are my own rules of thumb regarding the gradient of this fatigue curve:
• Athletes with very strong endurance or who are long duration specialists, exhibit fatigue curves of ~6%. In other words, as the distance doubles, athletes with strong endurance lose ~6% of their power.
• Balanced athletes with average levels of endurance or mid-duration specialists (Time Trialists, Olympic Distance Triathletes etc.) exhibit fatigue curves in the realm of ~8%.
• ‘Top end strong’/Anaerobic athletes exhibit fatigue curves of 10% or more.
These numbers imply steady-state endurance (@ ~60% VO2max) of 90minutes+ for anaerobic athletes, 3hrs+ for mid-duration specialists and 12hrs+ for long distance/IM specialists.
Delving into this fatigue curve in a little more depth, from the database of field data that I have collected on a large number of top AG and pro athletes, I have compiled the following ‘ideal’ power-duration curve for (male) Ironman athletes.
The first number on each point represents the power duration (in minutes, for example, 0.1=6 seconds), while the second refers to the % of max power held for that duration.
So, using these numbers, in a basic development sense, if an athlete lacks the strength/power to hit max power numbers better than 4x their 2hr numbers, strength/power may be limiting. On the flipside, if an athlete is unable to hold 1/4 of their max power for a 90min session, endurance may be limiting.
Following this basic assessing and addressing of the foundational qualities, consideration can be given to specific development towards the athlete’s event. In the world of Ironman racing, this means both training to hold progressively higher % over longer durations and, just as importantly, since this is a long term project, identifying the % that they will realistically be able to hold for the next race.
For an elite Ironman competitor, this may be 21% of their maximal power, for a fit but not fully ‘Ironman developed’ athlete, it may be closer to 18%. For a novice athlete with a longer race duration, still working on basic preparation, it may be closer to 15% (lower than their ‘basic training’ intensity!!)
Ironman athletes are fundamentally, strong, fast, fit athletes (who are powerful but shy of world class short duration power) who then lay down ~6,000 hrs of specific endurance training to increase their economy, their fat oxidation and the consequent power that they can hold over the tail end of the curve by 15% or more.
In terms of development then, rather than focusing on a particular event, an athlete with a young training age is better served focusing on one of 2 general athletic weak points. Put simply, if you lack the ability to put out 4x your 2hr power in a maximal effort, focus on the strength end of the curve. If you lack the ability to hold 22-26% of your max power for sessions in the 60min to 4hr range, focus on the endurance end of the curve.
I find the power-duration curve to be a very useful ‘check-in’ tool with the athletes I work with. I hope you also find some value in this approach.