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Hitting the Wall

Photograph courtesy of

Some years ago I wrote a blog post about the importance of pacing during long rides. How cycling too hard at the start of an endurance event leads to a feeling of fatigue, light-headedness, tunnel vision, and confusion. In other words, a bonk.

I hear “bonk” being used to describe muscular tiredness. A bonk is more than that. Runners refer to “hitting the wall.” In German, this is known as “Der mann mit dem hammer.” Likening the sudden drop in performance to being hit with a hammer.

Graphic courtesy of

A hallmark of bonking is a sudden and overwhelming feeling of running out of energy. This happens when you have exhausted your body’s glycogen stores, leaving you with abnormally low blood glucose levels. Your muscles have run out of glycogen, and your brain has told your body to stop exerting itself.

Your liver converts glucose into glycogen in a process called glycogenesis. Glycogen is stored in the liver and the muscles and is the primary fuel source for endurance athletes,

How can you tell if you are about to bonk? Sadly humans do not come with the equivalent of a “Low battery” warning. You don’t know that Der Mann mit dem hammer is behind you until he hits you. By then, it is too late to do anything about it.

Graphic courtesy of

How can you prevent bonking? Carbo-loading before an endurance event is a common practice. This ensures that your initial glycogen levels are maximized. That means consuming complex carbohydrates. Pasta often comes to mind as a complex carbohydrate. peas, beans, whole grains, and vegetables are also sources of complex carbohydrates.

Carbo-loading can ensure that your glycogen tank is full before you start riding. You need to make sure that your glycogen tank is kept topped-up during the event. This means eating regularly during the event. Some people like energy bars for convenience but foods like fruits, nuts, and potato crisps all work just fine.

Photograph courtesy of

What to do if you have let your glycogen tank empty completely, and you are bonking? You need to quickly eat some simple carbohydrates that your body can quickly absorb in order to raise your blood glucose levels again. Simple carbohydrates include energy gels (make sure you drink water with these), kaya sandwiches, sugar cubes, or sweets such as jelly beans. Sugary drinks like Coke, Gatorade, and fruit juice are also good sources of simple carbohydrates.

Photograph courtesy of

You need to also rest until you, hopefully, recover enough to continue cycling.

It is possible to train your body to convert glucose to glycogen more efficiently. In other words, to improve aerobic performance or the production of energy from chemical reactions that use oxygen. The aerobic energy system is the primary power source for endurance athletes.

Producing energy anaerobically, in other words, without using oxygen, is impossible to sustain for more than one to two minutes.

You may also hear about producing glucose from fat via a process called gluconeogenesis. This appeals to endurance athletes because the human body stores orders of magnitude more fat than glycogen. Being able to convert stored fat into glucose would mean the end of bonking.

The debate between proponents and detractors of Keto diets and being keto-adapted to take advantage of gluconeogenesis is fierce. I won’t enter that debate. You’ll have to research that topic yourself.

For the kind of riding I do, complex and simple carbohydrates in nasi lemak and cendol should stop this from happening to me.

Cyclist graphic courtesy of
Wall Photo courtesy of Jason Dent at

The Hardest Lesson

Most important lesson

Two weekends ago I rode 450km / 280mi over three days, including the 160km / 100mi Avillion Coastal Ride.  Which pales in comparison to the 642km /399mi within 40 hours that a number of my friends rode last weekend, as they attempted the BRM600.  The longest cycling event in Malaysia to date.

Not everyone who starts events like those are able to finish.  Some are stopped in their tracks by mechanical faults.  Many more suffer the drawn-out fate of succumbing to cramps and fatigue in the latter stages of the ride.

Which got me thinking about what it takes to not only complete an endurance bike ride, but to do so without feeling totally wiped out afterward.


Image courtesy of

There are a few things to do to prevent the dreaded DNF (Did Not Finish).  Such as making sure your bicycle has been recently serviced, carrying the tools and spare tubes needed to make roadside repairs, fuelling up before the event, and eating and drinking regularly during the ride.

Even if you do all of the above, you still run the risk of DNF-ing, or struggling to the finish, if you do not heed the following advice.  The #1 thing cyclists need to remember is:

Comfortably completing an endurance event is not about how you feel during the first 30% of the ride.  It is all about how you feel during the last 30% of the ride.

Cycling slowly early in a ride, when I felt fresh and had good legs, was hardest lesson for me to learn.  When I first started doing century rides, I would go out too fast and too hard.  Even when I was drafting, which is a recommended strategy for conserving energy, I would tag onto a group that was riding too fast for my fitness level.

The inevitable would happen after about 100km / 62mi.  Fatigue would set in.  I would get light-headed and experience tunnel vision.  The last 30% of the ride would be a battle of survival as I fought cramps and exhaustion while my speed steadily dropped into the teens and below.


Graphic courtesy of

Now  I know better.  I let other riders shoot off like fireworks when the starting hooter sounds.  I settle into a pace which is slow enough for me to breathe through my nose.  If there is a group of riders who are riding at my pace, I draft behind them.

This usually feels too slow.  But I know from experience that going slowly at the start allows me to finish the ride strongly.  I pick up the pace in the second half of the event, when I overtake the girls and guys who set off like rockets and then exploded into a dazzling display of bonking.

Pacing myself, and metering my effort in the first 30% of a long ride, has become my golden rule.

It ensures I finish the ride like this

smiling emoji

and not like this

exhausted emoji

Heads Down at the Terengganu Century Ride 2013

Courtesy of Terengganu Century Ride

Courtesy of Terengganu Century Ride at

Keat and I joined 1,000 other cyclists from all over Malaysia, Singapore and Thailand for the 2nd Terengganu Century Ride.  The ride started and ended in Kuala Terengganu (KT), the capital city of the east coast state of Terengganu.

KT is a six hour drive from Kuala Lumpur (KL).  We left KL at 6am and so had time for lunch at the Permai Hotel, the official event hotel, before we collected our numbers.

Photo courtesy of Roda Pantas magazine

Photo courtesy of Roda Pantas magazine

The expectation in Malaysia is that any organized ride that has a registration or entry fee provides each cyclist with a jersey and a finisher’s medal.  The TCR was no exception.  I though the jersey was a particularly nice design.

TCR Jersey

It was clear from the moment we stepped into the hotel that this was going to be a very well-run event.  There was a nice display of bicycles in the lobby.  There were separate goodie bag collection areas for each of the five participant categories.  We had our timing chips checked to ensure that the right name was associated with each rider number.  Teams with a support vehicle (must be nice!) were given large identifying windscreen stickers, and explicit instructions  for where to park before the start of the event.  There was a little bike expo where you could buy gels, bars, bottles, sun glasses, helmets and so on.

There were also three rider technical briefings spread across the afternoon.  Keat and I were good boys and went to one of them.  We did sit at the back of the room though.  Just like we used to do in school.  But we paid attention.  Just like we sometimes used to do in school!

TCR Briefing

Photo courtesy of Terengganu Century Ride

We had hoped to ride along the beach that evening, but we weren’t able to.

TCR Rain

Instead we went for a wet walk to check out the start area for the ride.  This photograph was taken earlier in the day.  It was still pretty quiet when we got there at about 6.30pm.

Photo courtesy of Pulse MediaCommunications

Photo courtesy of Pulse MediaCommunications

The elves must have been hard at work overnight.  By morning there was a Start/Finish gantry, complete with overhead timing transponders, along with barriers, banners and escort vehicles in place.

Photo courtesy of Roda Pantas

Photo courtesy of Roda Pantas

It rained again in the night, but it was dry and overcast by the 8.15am start time.  Keat and I hung out at the back of the pack behind the start line.  We didn’t want to get run over by the three hundred or so riders who would finish this 160km event in under five hours.

Photo courtesy of Pulse MediaCommunications

Photo courtesy of Pulse MediaCommunications

The ride started with a loop through the city.  Including a stretch through Chinatown along Jalan Kampung Cina, which is one of the oldest streets in KT.

Bike-eye view courtesy of Peter Lim

Bike-eye view courtesy of Peter Lim

The route then took us inland and north for 85km before a right turn at Guntong pointed us toward the coast.

TCR 2013 Route

One of the highlights of this ride (I’ll get to the lowlight) was the cheers we got from the throngs of primary school children waving at us from behind their school fences as we rode by.  We did ride past quite a few schools.  All of which seemed to be on a break as we came by.

We had a few other spectators along the way.

Photo courtesy of Roda Pantas magazine

Photo courtesy of Roda Pantas magazine

It was relatively cool at the start, but it did warm up steadily as the kilometers ticked by.  So the water stops were very welcome.  Another highlight of this ride was the volunteers at the stops.  They did did a great job handing out bananas, water and ice.  Both to riders who were happy for a bit of a rest, and to riders who were pushing for fast times.  At least one such rider needs to practice his drink grab though.

Photo courtesy of Roda Pantas magazine

Photo courtesy of Roda Pantas magazine

The course was relatively flat.  Much like the Netherlands is.  And much like the Netherlands, it was windy.  Nice at the start of the ride, despite being a headwind, when it was still cool.  Not so nice as a headwind after the temperature had risen.

The wind direction and wind speed changed throughout the day.  I had a headwind for 35km, then a crosswind that became a tailwind that reverted to a crosswind until the turn at Guntong.  The tailwind from that point was short-lived.  By the time I made a sharp right turn at the 90km mark the wind was changing direction yet again.  It became more and more of a crosswind for the 10km to the coast.  Along the coast it was a steadily stiffening headwind for the remaining 60km.

The annotations on the route map below show wind direction and wind speed at the start, and what they were at the point I had reached after riding for one hour, two hours, three hours and so on.

I have never spent so much time in the drops.

TCR 2013 Route with Wind

The views along the beach were nice, but they were hard to appreciate with my head down as I tried to find respite from the wind.

Photo courtesy of Terengganu Century Ride

Photo courtesy of Terengganu Century Ride

The gusting headwind made the last 30km or so feel interminable.  Thankfully I didn’t feel as bad as I did during the last 30km of the Kuantan Century Ride.  I did a better job of managing my core temperature during the TCR.  But I started to cramp a little, and bonk as well.  I didn’t drink enough, and I should have eaten more during the ride too.

The wind was the lowlight of this ride.   The only negative though, and not enough of one to detract from a very enjoyable event.

The TCR 2013 Event Director, Mr. Zulkarnain Shah, the members of his organizing committee, the army of volunteers, the Royal Malaysian Police and the Malaysian Red Crescent all helped make this event enjoyable and as safe as possible for all the participants.

The route was well-marked with large arrows at eye-level.  Busy intersections were manned by police personnel who made sure that riders did not have to stop for traffic.  There were dozens of mobile marshals on the course to provide assistance where needed.  Including acting as outriders for cyclists making their way along vehicle-crowded roads as the route came back through the city on its way toward the finish on Jalan Pantai Batu Buruk.

As we came to a stop after 161km we got our finisher’s medals.

TCR Medal

And after hours of heads down in the wind it was heads up for the post-ride entertainment.

Photo courtesy of Terengganu Century Ride

Photo courtesy of Terengganu Century Ride