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Ronde van Drenthe - The Hardest Day in my Life
March 14, 2013  

Supplied by By Dr Carol Austin and Trevor Court from ActiveWorx

On Saturday 9 March 2013, Team MTN-Qhubeka p/b Samsung lined up for the Albert Achterhes Pet Rondevan Drenthe,a UCI 1.1 race in the northern part of The Netherlands. The conditions were miserable; wind, pouring rain and temperatures hovering around the freezing point. Of the 155 starters, only 32 riders would finish including two of our young neo-pros Algerian Youcef Reguigui and South African Johann van Zyl who finished 24th and 28th,respectively. 

That was the hardest day of my life on a bike,” said Johannvan Zyl. “Everything happened. I crashed, I punctured and I froze. So I’m just happy to even finish the Ronde van Drenthe as 28th.”

The 200km flat route in the Drenthe included both open farm roads and technical cobbled sections (Fig 1).The racing was on from the start, and the wet slippery roads and grizzly conditions contributed to the progressive annihilation of the peleton. Alexander Wetterhall secured the win for Team NetApp-Endura when he broke away from the leading group of 12 with 30km to the finish. Johann finished within what remained ofthe peleton in an official time of 5h04m30s (+7m43s).

Fig 1:Ronde van Drenthe Route Map

SRM Data Analysis

This is what a tough day in the office looks like (Fig1) and that’s only half the story. Photographic imagery  reflects muddied grimaces and glazed eyes reminiscent of WWII battlefield heros. Video footage highlights the race speed and treacherous conditions en route.

Key Summary Data (Figure 2):

Time: 5h11m41s

Distance: 199km

Average Speed: 38kph

Average Power: 270W

Normalised Power: 308W

Intensity Factor: 0.833

Average Cadence: 82rpm

Median Cadence: 95rpm

Energy Expenditure: 5057calories

Average Temperature: 2.4°C(Wind Chill Factor -4°C)

Fig 2: Johann van Zyl SRM Data file - Ronde van Drenthe(200km, UCI1.1)

T: Time, P: Power, H: Heart rate, S: Speed (kph), C: Cadence, A: Altitude (m),D: Distance (km), E: Energy(kilojoules)

­Repetative In-Race Sprints

Our training philosophy is simple; “Train to the demands of the race”. This is why our athletes race with their SRM Training Systems, and why we spend significant time analyzing the data.

European one-day races place a significant demand on anathlete’s neuromuscular system.  To understand the accelatory demands of this race we used WKO+ analysis software to identify all accelerations of >800W of one-second or more duration. These sprint-like efforts occurred 67 times during the race, and ranged from 1-10s in duration. Astonishingly, twelve of these accelerations occured during the first 7km of racing (Fig 3). We guess that’s what you get for placing a sprint prime at the 5km mark!

When we did the same analysis on Jay Thomson’s winning 5-hour 2013 South African Championship Road Race file, the contrast  was clear. There were less than half, sprint-like accelerations; 28 to be precise. This is no surprise to us as our historical data of South African races indicates that an athlete is unlikely to do more than thirty sprint-like efforts in any race. This contrasts significantly with the typical demands of European one-day racing. The technical nature of European routes, the increased peleton size and depth of competition means that the battle is way more charged. It is not unusual to find 100-130 sprint accelerations in a 5-hour race.

Why is this important? Well if you don’t know it, you won’t train it. If you don’t train it, you won’t have it when you need it. And then it’s “Kaboom – race over”! So, while doing fifty sprint efforts in a training session might sound like unnecessary self-flagellation to some, it just may be what our athletes needs to prepare for success in Europe.

Fig 3: Acceletory efforts >800W during the First 7km of Racing

T: Time, P: Power, H: Heart rate, S: Speed (kph), C: Cadence, A: Altitude (m),D: Distance (km), E: Energy (kilojoules)

Five Hours inthe Freezer

The weather conditions were extreme. Imagine riding your bike for 5-hours in the freezer (-4°C ) on slipperly free rollers while you’re being  showered with rain and mud.Success or failure will be determined by your preparation, experience,re-fueling, equipment, clothing, and mental fortitude. And of course to some extent, “Lady Luck”.

Energy expenditure in the race was substantial at over 5000 calories, equivalent to the energy in 50 bananas! Refueling and hydrating proved extremely difficult. Frozen, gloved hands being overwhelmed by the simple task of unwrapping energizing gels and bars.

The last 50km proved to be the most cruel and cold forJohann. His energy supplies were depleted, and dehydration and fatigue were setting in. Sports scientists have shown that cold weather increases the riskof dehydration1 because there is little physiological stimulus to drink. In cold conditions a great deal of “invisible” vapourized water is lost in the breath (respiratory fluid loss). Thirst sensation, however, is reduced by up to 40%. Why?  Well, one of the body’s responses to cold exposure is peripheral vasoconstriction. The body reduces heat loss by diverting warm blood away from periphery. This results in a increase in the blood volume at the body’s core.Because of this diversion of fluid to the core, the brain does not detect the decrease in total blood volume and increase in blood sodium that would usually trigger the release of fluid balance regulating hormones (like argininevasopressin, AVP) that stimulate thirst and water conservation in the kidney.As a result the body becomes progressively dehydrated, and eventually athletic performance tanks off.


Johann’s Secrets to Success:

#1: Position. Position. Position. In the toughest races, only the best-positioned athletes will survive.A race can be super hot from the start. Be Prepared! i.e. Properly warmed-up,alert, and well positioned.

#2: Guts, character and an absolute will to succeed (and survive) on a very bad day “in the office”.

Johann van Zyl


Team MTN-Qhubeka trains and races with SRM Training Systems


Team MTN-Qhubeka is coached by Dr Carol Austin and Trevor Court of Activeworx



1. Thirst sensations and AVP responses at rest and during  exercise-cold exposure. KenefickRW et al. Med Sci Sports Exerc. 2004 Sep; 36(9):1528-34