Ironman World Championships 2016

Power and Pacing in Kona with SRM

Michi Weiss Powers to 3rd Fastest Bike Split on the Big Island

When SRM sponsored pro triathlete Michi Weiss’ alarm went off at 3am on 8th October 2016 signaling the countdown to the 0625 pro start of the Ironman World Championship, he was not expecting the day to unfold in quite the way it did! At least the Kona weather was predictable, if not the racing. The infamous heat and crosswinds were ever present, even if the day’s peak temperature was around 3C lower than in 2015 - when north of 34C with 80% humidity, lets not split hairs, it’ s still hot!

SRM Data 2015 vs. 2016

Duration 4:28:26 4:24:35
Distance 180km 180km
TSS 271.3 278.5
Work 4,824 kj 4,846 kj
NP 311 W 318 W
W/kg 3.69 3.77
IF 0.78 0.80
VAM 221 m/h 268 m/h

AVG and MAX | 2015 vs. 2016

Power 299 W AVG / 831 W MAX 305 W AVG / 966 W MAX
Cadence 84 RPM AVG / 109 RPM MAX 86 RPM AVG / 114 RPM MAX
Speed 40.3 KPH AVG / 68.7 KPH MAX 40.9 KPH AVG / 75.6 KPH MAX

As you can see above, Michi improved his average power and speed year-on-year. Indeed, he averaged 290W in the 2014 race so he has actually improved his average power each year for 3 years running and by over 5% in total, which is pretty impressive for a guy who already produces more absolute watts than any other competitor in the field. So one might think that there is little improvement to be had on the bike going forward. I would disagree and I will explain why later in this article.

This year Michi’s stand out performance for me was in the water. His bike performance was very impressive but there are certainly always areas for improvement. Unfortunately he was not able to showcase his running ability this year because the manner in which the bike leg was executed depleted his legs. Ironically, his running legs started to improve about 35km into the run because he had been running so slowly up to that point that it had actually allowed some recovery from the bike effort to take place! But that is Kona for you. Weird and wonderful all day long.

The Swim – ‘Don’t wish it were easier, wish you were better.’

Well, Michi got better alright! Anyone following these articles over the last few years knows that Michi’s priority has been to improve his swim. Easy to talk about, very hard to do. Nevertheless, a 54:03 split and a 6-minute improvement over 2015 suggests he did it. I cannot overstate the importance of this breakthrough for an athlete who can already bike and run with the best. Let me explain:  Last year Michi swam the 3.8km in 60 minutes, leaving him around 9 minutes down on the lead group. Even with his prodigious bike power this ultimately proved to be too big a gap to bridge and so he was relegated to playing a catch up role all day long – his usual modus operandi – and slogged his way to a very commendable 16th place overall. 

This year he exited the water just 6 minutes down on the Frodeno/Potts group and right in the mix of athletes possessing some serious bike power, including Boris Stein, David Plese and former World Champion, Sebastian Kienle. While I believe that this swim improvement is going to be a game-changer for Michi going forward, like any step change in performance, it came at a cost and required some considerable compromises to be made this year in overall training volume distribution. Essentially, he swam more and biked less (see the pie charts below). I believe that this may have now left him somewhat vulnerable on the bike over the Ironman distance, if not at the 70.3 distance.  Let me explain by first taking you through Michi’s race file which, while representing the days’ 3rd best bike split, the highest average power, actual or Normalized of any athlete in the field, and also an improvement over the previous year of some 6 Watts, left me thinking that there is still more work to be done on the bike. 

Robbing Peter (the biker) to Pay Paul (the Swimmer)...

Great Legs…For 70.3 Racing

A Physiological Game of Chess

As a rule, Michi does not make rookie errors on a bike such as over pacing or ’burning matches’ (*see boxout for explanation). But, while his excellent swim put him in the best position of his career at this stage in the World Championship, he still had to chase down and make decisive passes on a bunch of in-form guys who know how to ride a bike.

“I’ve never caught those guys so quickly in a race before. It felt kind of strange!”

In the graph above you can see that Michi pushed an average of 340W of Normalized power (330W actual) out to the Hawi turnaround, an effort which also included nine surges (pink spikes) at between 120% and 155% of his Functional Threshold Power (400W). This is the effort that was required to catch the Kienle group. As such it was necessary and worthwhile. It may look to the untrained eye, or even to the trained eye unfamiliar with Michi’s abilities, like a reckless use of precious energy but it was not. Those overtaking power spikes were actually very controlled and far from all out efforts. My pre-race guidance to Michi was to minimize time spent above 380W and in fact his peak 5-minute power over the entire course was just 377W. The one criticism I have is that when Michi caught this important group after just 50km (!!), he should have tucked into the pace line and kept his nose out of the wind for the rest of the day being patient, biding his time, eating, drinking, recovering and generally doing as little extraneous work as possible. This would have given him the best chance to show off his run which is actually in great shape, not that you would think so from his subsequent marathon split. 

“I only got my legs back at the end of the run!”

But this is not what Michi did. Because his swim usually leaves him with so much work to do on the bike, he has rarely experienced the luxury of being able to sit in the lead group for most of the bike leg, where even a 10-meter drafting rule allows for around 20W less work to maintain position in the group. For Michi this would mean steady state cruising at around 270W-280W, which is very comfortable for him. Instead, rather like the story of the scorpion and the crocodile – google it – Michi went to the front and pushed. Indeed, he even got a small gap to the group after the descent from Hawi and was at the front well after Kawaihae. In any other race this mat well have turned into a race winning gap, but not at the World Championships with the best 50 Ironman triathletes in the world strung out behind you. And so he was not allowed to get away and instead spent rather too long dangling off the front using up precious energy reserves. Furthermore, anyone watching the race footage would have noticed the difference in cadence between Michi and the rest of the field on the descent from Hawi. While most were using the descent as a chance to freshen up their legs, Michi was spinning out of his Atomic High Performance coated 56-tooth chain ring at well over 100rpm and 280W!. For an athlete who usually rides at 80-85rpm, an effort of 100rpm+ for 5 minutes is neuro-muscularly challenging and certainly contributed to feelings of muscular fatigue that Michi reported right around this point in the ride.

Spinning It Up

It is around about 100km in that the Kona bike course likes to bare its teeth and the temperature invariably starts to climb, the cross winds in the lava fields get serious and all this when every athlete, irrespective of conditioning level, is getting tired. That is why almost every power file you look at from Kona looks like a version of this below:

Temperature Rises, Power Falls

Now heat, or more specifically, acclimatization to it, is just a part of racing in Kona. If you don’t like the heat, don’t go to Hawaii! But no matter how well an athlete has adapted to these crazy conditions, we almost always see some drop off in average power on the way back into town. The goal of course, is to minimize that drop off. The only way to do this is to ride very conservatively on the way out, which Michi did not do largely out of necessity, and to have built the bike specific endurance required by the Ironman distance by having performed many entirely aerobic rides of 4-6hrs mostly on the race bike, which, due to his commitment to swim improvement and 70.3 racing this year, Michi had not done. The result was a very powerful 90km effort followed by a very difficult and gutsy 90km effort, which even though it came in at just 84% of the average watts on the way out, felt much harder. The death knell for Michi’s run had already rung out somewhere around Waikoloa!

Michi Takes Charge But At What Physiological Cost?

‘Perfect Numbers, Like Perfect People Are Very Rare’

So the lesson I take from this is that we need to readdress Michi’s bike volume next year while further improving his swim and at least maintaining what is already really good running ability. He has also built great overall strength this year in the gym (partially due to the necessity of rehab following knee surgery), which is really important in both the prevention of soft tissue injury and in muscle fibre recruitment when fatigued. That said, bike volume should take priority in the Spring of next year.

The lesson age groupers should take from this is that while numbers don’t lie, they can certainly mislead – Michi’s best ever Kona bike file and worst ever run performance must mean that he has the Ironman bike dialed and his run sucks, right? Not necessarily. Training and racing data is nothing without context. Feedback from the athlete, from both key training sessions and races, is just as important as the numbers generated by the technology. Only by considering both simultaneously can you hope to gauge performance. Only by putting an SRM on your bike can you hope to achieve synergy between man and machine!

What has #IMKona2016 taught us about Michi’s performance profile?

·      His improved swim has given him a broader range of racing options, which will likely increase his chances of victory in all races going forward.

·      A wider range of strategies on the bike will need to be considered. A more passive-aggressive style in Ironman racing versus outright attack for example?

·      The new Diamondback Andean is going to take the triathlon world by storm, it is proven fast and functional with triathlon specific features. 

·      Michi’s power-duration curve is as steep as ever, but optimized for 70.3 race distance. The long end of the curve now needs underpinning in order to improve power/efficiency over 180km.

·      Top 5 in Kona remains the goal and so heat acclimatization pre-race is key. Seeking out more ‘hot’ races during the year would be no bad thing together with training blocks in the heat.

·      Michi’s nutrition package designed by GQ-6 is superb in delivering optimal fueling without GI issues even in the highest temperatures.

·      Michi is a fully rounded, worldclass triathlete  now possessing the guns to achieve a top 5 Kona placing in the next few years. No longer is he a great bike/run specialist who unfortunately has to get wet first!

As always, we would like to thank Michael Weiss for letting us analyze every pedal stroke he makes. And to congratulate him on his fastest ever bike split in Kona. More than that, to really take my hat off to the step change he has managed to make in his swimming ability. Although I know the work that went into that, it is a considerable achievement and one that will fundamentally alter how Michi prepares for races in the future


Garth Fox (MSc)  - Sports scientist & High Performance Coach

With assistance from Peter Leo

‘Over-Pacing’ – Why does it matter?

Listen to any cycling TV and the chances are there will be mention of ‘overpacing’ or ‘going too deep or‘ burning of matches’ and how it should be largely avoided if optimal endurance performance is the goal. But what is actually meant by these terms? To understand that we first need to get a grip on the idea of ‘threshold’.

Essentially ‘threshold’ describes the point at which if we work much harder we will have to stop a lot sooner. But less well understood is that there are actually 2 physiological events that take place along the exercise continuum from working very easy to very hard – the first is usually termed ‘lactate threshold’ and is not really felt consciously at all by the athlete but it is there nevertheless and simply describes the point at which blood lactate first rises above baseline levels. The second is called Critical Power (or Critical Speed if referring to swim and run disciplines) and is the point most of us think of as ‘threshold’. For our intents and purposes at least, this is similar to Functional Threshold Power (FTP), which is a well-known concept to many endurance athletes, and so we will use that concept here.

It is when we exercise at intensities above our FTP that we run into problems, especially in long course events like Ironman. The work we do above this point uses up something called our ‘anaerobic work capacity’ (known as AWC, W’ or W prime in the scientific literature) of which we have a fixed amount and when it is used up we have no choice but to slow down so that it can be replenished which can take a long time to do unless we come to a complete standstill – not great if you are in the middle of a race! This fixed amount of AWC is used up more quickly the more we surge through our FTP. This is why, in Michi’s case, he was forced to slow down on the way back to T2 from Kawaihae (heat also added to this power reduction) – essentially to allow his AWC to recharge. Take a look at the file and you will see, in the same way that a bank loan eventually requires repayment, Michi borrowed heavily from his AWC account in the first two hours of riding but that ‘loan’ was then called in and was not really repaid to any great degree until very late in the run when he actually started to get his legs back deep into the marathon!

Because an individual’s AWC account can be quantified through testing (how many matches you have to burn) it is possible to measure exactly how much you have depleted your reserve and thus know exactly how much you have left (how many matches you have left to burn) before you will be forced to slow down considerably. These numbers will increasingly be available to the cyclist on his bike computer and via ‘wearables’ on the fly and may well change how races are raced in the future. 

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