Sunday, 30 October 2011

Beachy Head Marathon – Illustration of the Race Focus Energy Fatigue Model

Hi, be prepared for a marathon post tonight!

Last weekend I raced the 10th Beachy HeadMarathon (previously known as the Seven Sisters Marathon for 21 years).  It was my tenth time, having raced it every year since moving to East Sussex in 2002.  Starting and finishing in Eastbourne, this is my local marathon, so along with the great views as we run across the South Downs completing a 26 mile loop, there is a great atmosphere from the 1750 runners and walkers involved, in addition to the tremendous support along the course from the many spectators, many who give me personalised encouragement due to recognising me from previous years.  Over the previous nine years my finish times have been reasonably consistent, ranging from my fastest of 2:57 in 2007, to my slowest finishing time of 3:11.  In both of these years I finished second, whereas I won the race on all of the other seven occasions.

The graph above shows my finish time plotted alongside my average weekly mileage each year for my 16 week build-up.  There are many aspects that account for the variation in finish time, which as the graph illustrates; the finish time is not directly determined by average weekly mileage.  Therefore within this year’s Beachy Head Marathon race report, I will attempt to provide an explanation into the many factors that influence trail marathon race performance, through an illustration of my newly released Race Focus Energy Fatigue Model.  Hopefully my fatigue model will find some agreement with your experiences of race fatigue, and hopefully lead to a greater understanding of things to consider in order to improve trail marathon and ultra running performances.

Before I describe my TOTAL preparation for this year’s Beachy Head Marathon, first a little background into what causes fatigue during endurance running.  Well as I have highlighted within previous blog posts, very little is actually known in terms of what causes fatigue.  Over recent years, the simple homeostatic failure model of fatigue, (homeostasis refers to remaining stable, or specific to the human body, functioning within a normal range) i.e. fatigue at the periphery within the muscles due to lactic acid, glycogen depletion or muscular damage/fatigue, has been clearly shown to be too simplistic!  Many observations such as: the finishing spurt, different pacing strategies for different race durations, lack of glycogen depletion/lactic acid within muscles when fatigued, and how interventions that solely act on the brain affect performance, all confirm that the simple homeostatic failure model (either peripheral fatigue or catastrophic central/brain failure) , is flawed.  Therefore the need for a new model!

Probably the most significant change over recent years is the increased acceptance that the brain needs to play an extremely important role within any endurance fatigue model.  The Central Governor Model proposed by Professor Tim Noakes, author of the Lore of Running, is probably the most commonly known alternative fatigue model.  The key feature of this model, shown above, is that it is an anticipatory-regulatory model, where the brain anticipates a future failure and so modifies behaviour specifically to ensure homeostasis is protected.  This modified behaviour is a decrease in the number of motor units recruited in the exercising muscles, or what I refer to as a change in the level of muscle activation.  Noakes and others have demonstrated that there is a decrease in muscle activation initiated by the brain when fatigued, They have identified some of the factors that lead to this reduced muscle activation, but haven't really explained how.  My Race Focus Energy Fatigue Model introduces a novel way to look at endurance fatigue and proposes a number of factors that influence the rate at which fatigue develops.

Race Focus Energy (RFE) could be thought of as concentration or mental effort.  It relates to the concept that it requires mental effort/concentration in order to remain focused whilst racing, in order to keep on running hard, out beyond one’s comfort zone.  (The term 'race' doesn't have to mean racing other competitors, it simply means that the run is a special occasion, where you are extending yourself, trying to run to achieve a certain goal.) Fatigue will occur when your supply of Race Focus Energy is depleted so it is no longer able to recruit exercising muscles above a ‘threshold’ level.  Or when the brain anticipates that at your current rate of RFE usage, depletion of RFE is imminent so alters the level of muscle activation to preserve the limited supplies of RFE.  The basis of the RFE fatigue model is that RFE is required in order to activate the exercise muscles above a threshold level.  At low levels of intensity, e.g. at a slow jog when 'fresh', it does not take any RFE to maintain the easy pace.  A slow jog when fresh is below the RFE threshold.  However as the race progress, as the body physiologically becomes less efficient, e.g. muscles fatigues, glycogen levels decrease, heart rate increases due to cardiac drift, to maintain a slow jog now may require RFE as the intensity, albeit rather low is now above the RFE threshold.

At the start of an endurance race, each runner has a limited supply of RFE, although this limited supply can be added to/topped up slightly during the race, however, the greater the supply of RFE at the start, the better the performance.  This therefore leads directly onto Training Principle No. 1 – Maximise the size of the RFE tank prior to race start.
The size of the RFE tank is determined by a number of factors including: Research on the Race, Research on Oneself, and the Surrounding Environment leading up to and immediately prior to the race.  Or to put it simply, the size of the tank is determined by one’s attitude to and expectations of the race; expectations to what will be encountered during the race and an expectation of how one will respond to these challenges. My TOTAL preparation in order to maximise the size of my RFE tank on the start line is to spend many hours researching the race.  What are the demands of the race?:  Total Time, Distance, Profile, Terrain, Daylight/ Darkness, Navigation, Possible Weather, Temperature, Clothing, Feed Stations, Food, Dehydration, Backpack, Fellow Runners, Loneliness, Support, Family/Friends.  I also spend many hours researching myself: WHAT do I WANT?  WHY do I WANT IT?  HOW MUCH do I WANT IT?  Are these WANTS realistic, based on what evidence?

Leading up to the Beachy Head marathon this year, because I had previously raced it nine times, I didn’t need to do any research on the race, as I already knew everything there was to know about the race.  I think the lack of time I spent researching the race also resulted in me spending less time than usual researching myself.  What were my aims/goals for this year’s race?  Having a DNF at Ultra Trail Mont Blanc, where I focused too much of the performance, and forgot about enjoying the journey, I feel I experienced an over-reaction to UTMB, by there being a minimal performance goal for this year’s Beachy Head Marathon.  Yes, it would be nice to win the race for an eighth time, and yes it would be good to run it in under 3 hours again, but there wasn’t really any thought in my preparation into WHY do I want this, and HOW MUCH do I want this.  There wasn’t the usual excitement of looking forward to the race, the real buzz associated with getting ready to really test myself as I strive to respond positively to the expected challenges that the race will create.  So my RFE tank on the start line was not as full as possible.

I suggest above that the amount of RFE one has on the start line is influenced by one’s confidence in that they will respond positively to the expected challenges that the race will create.  Yes, self confidence leading up to the race has a large effect on the level of RFE within the tank, and also the rate at which RFE is being consumed during the race.  One factor that largely determines one’s self confidence is their recent physical training.  If the physical training has been going well, then confidence is usually increased.  How one determines whether physical training has been going well is an important issue, which I will return to, as are a number of other benefits from physical training.

The size of the RFE tank is also determined by the Surrounding Environment leading up to and immediately prior to the race.  What I mean here are things like other stresses within you life, whether work related, family related, stress, tiredness, feeling drained, worn-out, stale etc.  All of these factors will have a negative effect and reduce the amount of RFE at race start.  For the last three years leading up to the Beachy Head Marathon I still felt drained from previous ultra trail races, 56mile London to Brighton (2008), UTMB (2009) and Pumlumon Challenge/High Peak 40 Ultra Trail races (2010).  Therefore my RFE was lower than usual, and hence why even though physically I was extremely fit, with the increase in my weekly mileage during these years, the performance didn’t directly reflect to the physical fitness due to the decreased RFE as a result of being worn-out/tired. 

Finally your surrounding environment prior to the race can, even at the last minute, reduce or increase the level of RFE within the tank.  If you are surrounded my highly motivated people and there is a real buzz then this can add that little bit extra to your tank.  Similarly if there is negativity, conflict, prior to the race, e.g. an argument with your partner, or having to listen to whinging and moaning from runners about injuries, or how tough it will be etc.  Then this can have a decreasing effect on the level of RFE.  Fortunately I didn’t have any of these negative experiences prior to last weekend race, in fact I had many positive experiences, especially from the successful Beachy Head Marathon Science Symposium that took place the night before.

Maybe you are beginning to think, nothing really novel above.  Apart from the term Race Focus Energy, there isn’t really anything to get excited about.  Possibly true, but I think the real revolutionary feature of my RFE fatigue model is what happens DURING the race.  Hopefully I can explain with the use of the following three figures, which include three important concepts; Rating of Perceived Exertion (RPE), Race Focus Energy (RFE), and Muscle Activation.

Rating of Perceived Exertion (RPE) is a common measure used within Sports Science research.  While doing physical activity, subjects are asked to rate their perception of exertion.  This feeling should reflect how heavy and strenuous the exercise feels to them, combining all sensations and feelings of physical stress, effort, and fatigue.  They are then asked to look at the rating scale while they are engaging in an activity, and to choose the number, between 6 - 20, that matches the description that best describes their level of exertion.  Research on running to exhaustion has shown that RPE is a better predictor of the time to exhaustion than any physiology measures.  RPE is influence by many factors, not just physical, and involves the integration and processing of multiple signals – feedback and feed-forward!  There is an increase in RPE when there is a mismatch of expectations to what’s encountered.

One can therefore interpret that not only does extensive research of the race and oneself within the TOTAL preparation increases the level of RFE on the start line, but if their is poor preparation in terms of visualising what one is likely to encounter during the race, then this increased likelihood of there being a mismatch of expectations to what’s encountered will increase RPE.

Looking at the figure above, you see that the level of RPE determines the about of Race Focus Energy that is required in order to provide the muscle activation to run at the demanded race pace.  A higher RPE will increase the amount of RFE required to activate the muscles.  The greater the RFE usage, the sooner it will be before your RFE tank is emptied, which results in decreased muscle activation, and hence a decrease in running pace.  The key to endurance running performance is therefore to reduce the rate at which RFE is being consumed!

The first obvious way to decrease the rate or RFE usage is to getting physically fitter.  Everyone knows that as you get physically fitter, it feels easier to run at the same pace as before, and therefore there is a decrease in RPE.  This concept matches most previous models, and is why there is such a massive emphasis on physical training.  However the novel aspect of the RFE fatigue model is that there is not a DIRECT link between RPE and RFE, as shown in the above figure.  The level of RFE being consumed for a set level of RPE can vary, and is dependent upon the amount of positivity or negativity that is being experienced at that moment of time.  The two figures below illustrate this; if you are experiencing positivity, this will cause the arrow relating RPE to RFE to rotate downwards, resulting is a lower RFE consumption for the same RPE.  So even though you know you are working really hard, i.e. at a high RPE, it doesn’t take much mental effort, it just feels easy, i.e. it is using less than normal RFE. Similarly in experiencing negativity, the RPE – RFE linking arrow will rotate upwards, causing an increase in the rate at which you use the RFE.  In this situation, even though you know that the intensity isn’t very high, i.e. a low RPE, it just feels harder than usual, a real struggle!

The key to TOTAL preparation in order to maximise endurance performance is recognising that receiving positivity and ignoring/rejecting negativity whilst racing can have a large effect on overall performance.  It is not just the final 1- 2 %, e.g. the icing on the cake.  This positivity/negativity has a SUBSTANTIAL effect on endurance performance.  Realising this, accepting that your race performance isn’t preset by your level of physical fitness is essential.  The next step is then to identify what factors can contribute to positivity and negativity, and be prepared to accept/reject these.  Listed below are a number of factors that affect me, but factors that affect you may be different.  This is where race reflection is so important.  Where you reflect back, to learn from what went well, what factors seemed to be related to running well, or related to achieving less than the ideal performance.

LIKELY sources of POSITIVITY - Racing / the competition, overtaking others; Internal feeling of satisfaction, i.e. running well, positive time splits, perception of speed, running non-stop to top of hill; Puffing and blowing hard; Feeling proud, support, family, friends, others; Being excited, unique experience; Feeling refreshed, sponge, water, food, break; Feeling easy yet running well, relaxed, ‘flying by’; Scenery, sunshine, warmth, dry feet, tail wind.

LIKELY sources of NEGATIVITY - Anxiety, doubt, lack of confidence/self belief; Getting tired, finding it hard/tough - counting down the miles; Muscle soreness, blisters - focus of attention!; Going slower than expected - a ‘bad day’!; Going faster than expected - will ‘pay’ for it!; Going off course - frustration, angry; Difficulty in taking on fluid/fuel; Being overtaken, slowing at a great rate; Conditions: rain, cold, heat, mud, wind, scenery.

So back to last weekend’s Beachy Head marathon.  I start the race with a reduced level of RFE due to poor preparation in terms of research on myself, although my surrounding environment leading up to the race was beneficial this year with there not being the tiredness/staleness of the previous three years.  The race starts and as usual it is an exciting feeling as I attack the significant climb at the very start resulting in extensive puffing and blowing.  After around three miles I am joined by Tom Morris a local runner from Lewes Athletic Club.  We run together up the short sharp climb before a lengthy descent down into Jevington.  This point during the race always results in my highest heart rate during the race, as I am able to really attack the short climb knowing that I have 5 minutes recovery on the descent.   Looking at my heart rate trace it shows I reached 179 bpm.  Although quite close to my maximum of around 186 bpm, it is less than previous maximum heart rates of 182 and 184 bpm achieved during 2009 and 2008 at the same point.  We reach Jevington, one of my time checks in 27:10.  I had planned a race schedule for 2 hours 59 minutes, and my target time at Jevington was 27:30, so I was 20 seconds up on schedule.

During the last year or so, although I still plan race split times prior to the race as part of my TOTAL preparation, I now tend to not pay attention to them during ultra races, as it can often lead to negativity, if ahead or behind schedule, which results in the RPE - RFE link arrow rotating upwards.  However, since I have extensive race split time data over nine years I decide that for the marathon I would look at the split times, as a measure of how I was going.  I think this needing to look at split times was mainly a result of my poor research on myself.  I hadn’t determined what I wanted from the race.  When I saw that I was 20 seconds up, it just confirmed that I was going okay, and hence no rotation of the arrow in either direction, as the time up was most likely due to the strong tail wind this year.  For the first time in 10 years, the wind was a tail wind on the way out!

Climbing out of Jevington, I could sense Tom giving me a ‘hurry-up’ as he ran immediately behind me on my shoulder.  Usually this wouldn’t bother me, but as one of my main aims of the day was to simple enjoy the journey, following this not occurring during UTMB, I decide I would get more enjoyment my easing of the pace and to let Tom take the lead.  So as we started the climb up to the top of the Long Man of Wilmington Tom gradually eases away to around 50 – 70 metres lead at the top, and I am happy that I can run at my own pace without distractions.  There is then a lengthy descent to checkpoint 2 (previously checkpoint 1 but an additional checkpoint/feed station was added this year at Jevington).  This is another of my time checks at around 8.8 miles reached in 57:30, so now 30 seconds up on my planned arrival time of 58:00.  Again, no rotation of the RPE - RFE arrow, as although there was an increased positive feeling of enjoying the journey, there was also some negativity in that I was running ‘within myself’ and I should be really ‘pushing harder’ as after all it is a race!  Being in second place wasn’t any cause of negativity as during the last three years, on all occasions I had been in second place till the later stages of the race.

There is a steep climb as we leave Alfriston towards the next checkpoint at BoPeep carpark.  To my surprise I am overtaken by a chap (Steve Nimmo from Orpington Road Runners) wearing a bright multi-coloured, extremely large/baggy t-shirt, (see photo lower down the blog post).  He looks like he is a fun runner on a gentle stroll.  There is an immediate rotation up of the RPE - RFE arrow due to the immediate negativity of dropping down to third, but probably more due to his t-shirt!  How can a fun runner, which I perceived him as, due to his nearly fancy dress costume runner simply stroll past me.  The immediate increase in Race Focus Energy actually ‘snaps’ me back into action.  I am back into race mode, and I am able to up the race intensity, there is an increase in RPE, but no further increase in RFE due to the satisfaction of ‘pushing hard’ again.  I get increased positivity from working hard again!

For the next seven miles or so, the three of us maintain an equal distance of around 50 metres between Tom and Steve, and 50 metres between Steve and me.  I passed my time check at BoPeep carpark in 1:22, exactly on my 2hour 59 race schedule, although again no rotation of the arrow, as although pleasing to be ‘bang on’ schedule, due to the tail wind I am well aware that it is unlikely that I will maintain the 2:59 pace.  Here you can see a clear demonstration of how time splits can limit your performance.  This calculation due to the perceived future slowing down, causes an upward rotation of the arrow, and hence results in an increased ‘drain ‘on the RFE.

As the three of us leave the feed station at Litlington (reached in 1:51, now one minute down on my schedule) and reach the top of the short but steep climb. Tom begins to significantly struggle, although his pace had been slowing for the last mile or so, but with Steve seeming hesitant to take the lead.  At 17 miles into the race all three of us for a brief moment are running side by side.  It isn’t for long as Tom soon drops off, and as I try not to look behind whilst racing, it is the last I see of him.  He later comments to me that shortly after we overtook him he really began to struggle.  He ends up finishing over 17 minutes behind Steve and I, in sixth place.  He attributes his extensive fatigue due to lack of nutrition/energy, however, I would imagine that going from leading such a prestigious marathon as Beachy Head, down to third place within seconds, probably resulted in a massive swing in his RPE - RFE arrow in the upwards direction.  I can only speculate, but perhaps this lack of energy he suffered from, was energy not in the form of glycogen/glucose, but Race Focus Energy; the key ingredient that enables us to run fast, as without the RFE there is not the required muscle activation.
With nine miles to go, it is down to a race between the two of us.  Steve sits immediately on my shoulder as we make our way to Cuckmere and cross the A road, before climbing up the extra hill that was added in 2003, which probably adds an extra two minutes to the race time.  (Hence why the weekly mileage/finish time graph above shows a race time of 3:01 for 2002, even though I actually ran the shorter course in 2:59).  We take our time going up the climb and it becomes apparent that Steve is quite happy to simply follow my pace.  On the descent back down to the Cuckmere valley before we start the first and longest climb of the seven sisters, I decide to put in an attack and see whether Steve is staying behind me by tactical choice, or hopefully as he is not capable of quicker. 

I immediately gain around 20 – 30 metres, and with the downward rotation of the RPE - RFE arrow I attack the next climb extremely hard making the most of the positivity of running hard and leaving him behind.  The climb I guess takes around 4 – 5 minutes and I am really ‘buzzing’.  I am running hard, receiving satisfaction from the extensive ‘puffing and blowing’, and the added joy of leading and possibly heading towards win number eight.  I am working hard into the strong headwind, the first time there has been a headwind on this last portion of the course in all ten times of my running the Beachy Head marathon, which causes a slight upward rotation of the RPE - RFE arrow as I reach the finger post at the top of the climb in 2:17, still only one minute down on my 2hour 59 min schedule, but with an immediately realisation and an increase in negativity ‘knowing’ that I will not run sub 3 hours!  Yes, I am now a strong believer that paying too much attention to race split times more often than not leads to a upward rotation of the RPE - RFE arrow.

 I then take a quick glimpse behind, expecting to see Steve a good 50 metres plus behind, but no. he is less than 20 metres behind.  All of that massive increase in pace has resulted in an actual lose of a few metres!  There is an immediate large swing of the RPE - RFE arrow upwards, as if instantly it feels like I am really struggling.  I therefore ease of the pace substantially in an effort to recover from the massive drain on my Race Focus Energy.  Within a few moments I go from high RPE but a low RFE, where it felt easy, to an immediate need to reduce the RPE in order to lower the level of RFE usage!

For the next 3 – 4 miles I set the pace at a reasonably comfortable level, with Steve happy to follow.  I am getting ready for a big effort to respond to a likely attack from Steve, because I have a feeling that we both know that if we are still together at the top of Beachy Head, with there being a little over a mile of descending to the finish, then due to the evidence from the previous race descents I would most likely result in being the first to cross the finish line.  It is at moments like these where extensive preparation in terms of research on oneself, i.e. race goals/aims, e.g. what do I want, why do I want it, and how much to a want it comes into play.  If one has these goals/aims clearly ingrained within one’s subconscious and conscious, the fact that one is so close to achieving their clear goals results in the RPE - RFE arrow to rotate downwards, which allows for an increase in running pace, causing an increase in RPE, but yet for the same level of Race Focus Energy.  Looking back now, if I had established a clear race goal of either sub 3 hours, and/or, winning the race, I feel that instead of ‘having’ to ease of the pace at the finger post when discovering that Steve was still close to me, I would have been able to maintain the increased high intensity of running without the actual high rate of RFE usage than actually occurred, that led to a substantial reduction in race pace.

With a little over two miles to go, as we start the final lengthy climb up to the top of Beachy Head, the expected attack from Steve occurs.  The increase in pace is dramatic, I immediately increase by pace in response but the massive increase in Race Focus Energy in order to increase my running pace is huge, and although there is the desire to stay with him, the brain senses that my rate of RFE usage is excessive, and even with there being less than 15 minute of running till the finish, the level of muscle activation being output from my brain is insufficient, and Steve pulls away, gaining a lead of 30 – 40 seconds in a very short space of time. 
One thing I have noticed is that the brain’s subconscious anticipation of exhaustion of ones’ Race Focus Energy appears to not only be influenced by the actual RFE usage rate at the present moment, but also the extent of the recent increase in RFE usage.  I think the fact that I was running at a reasonably comfortable pace, with this being not at too a higher level of RFE, to then immediately to go to extremely high levels of RFE led to the insufficient muscle activation needed to stay in contact with Steve.  I’m sure that if I had maintained a semi-uncomfortable pace, rather that a semi-comfortable pace during the proceeding 3 -4 miles, then I would have been able to run faster up the final climb.  It wasn’t physiological reasons that prevented me from keeping up with Steve, as my heart rate trace shows that even with maximal effort; my heart rate did not go higher than 167 bpm!

At the top of the climb I am probably around 40 seconds behind Steve, I run hard all the way to the finish, running the last 0.76 miles at an average mile pace of 5:19, albeit losing 79 metres in elevation, reducing the lead slightly, and finish 27 seconds behind in an official time of 3 hours 2 minutes and 55 seconds.  The photo below shows be running downhill to the finish with my two boys Robert and Chris trying o keep up with me!  Yes, another immediate rotation down of the RPE - RFE arrow as I run past my family.

Interestingly as I finish there isn’t any disappointment at running 30 seconds slower than last year, or in not winning, as I did enjoy the journey, this being a big improvement upon UTMB. However, within a race, I always try to extend myself, to run to my limits, to totally exhaust my Race Focus Energy, and I feel that I didn’t really do that during last weekend’s race, probably largely a result of the lack of research on myself during my TOTAL preparation, not as total as usual. The physical preparation had gone well, as evidenced by the physiological ease at which I completed a 3:02 Beachy Head Marathon time, with my average heart rate of only 163 bpm, with this being significantly lower than the average heart rates of 167 - 171 bpm during previous year's Beachy Head marathons.
Well another marathon effort of a blog post.  Hopefully you have managed to maintain focus throughout, and are not totally blog fatigued!  It is difficult attempting to explain my Race Focus Energy Fatigue Model within a blog post.  The best bet, if you want to find out more is to get to one of my upcoming talks.  Yes, talks!  Not only have I got my talk up in Cheshire on Saturday 19th of November, which I have previously mentioned, but on Saturday 3rd of December I am doing a talk down in Dorset as part of the Endurancelife Live More Lectures Series.  My focus of my talk in Dorset is on UTMB, however, I will have a few slides to do with the Race Focus Energy Fatigue Model, as it plays such an important part during endurance trail running.  In addition, if you buy me a beer, I will talk to you all night about it.  And as evidenced by the length of my blog posts, all night could in fact mean all night!

Time to sign off with some words related to tonight’s post;
“Often it is too easy to accept a less than satisfying performance due to an acceptance that physically you are not capable of better, however, as soon as there is the realisation that simply the way you think and respond to the challenges that you encounter during the race can alter one’s performance, one is capable of achieving so much more!”  Stuart Mills, 2011.
All the best with your interpretation of my model,



  1. Hi Stu

    another great piece of writing. What you are describing sounds like the "Anticapatory Regulation" mechanism. IF you haven't already seen this paper, it would be worth a read

    This is also a very interesting article I think you might like

    Must catch up for a run soon !


  2. Stuart, marathon post indeed. Read every word - some real food for thought. Thank you for sharing.

    How do you ensure your RFE is as high as possible when you may be going into a race with 1 or 2 individuals who have shown some fantastic race form and are on paper more likely to perform at a higher level?