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The Jungle Marathon:

Ultra Endurance Running in the Heart of the Amazon

Jungle Marathon.jpg

​It was during breakfast, the morning after completing the Marathon des Sables and whilst recovering in Ouarzazate's Berbere Palace, that discussions began as to what should come next. The Marathon des Sables was no longer recognised as the toughest footrace in the world, at least not by those on the ultra-endurance adventure racing circuit. The general consensus was that the true toughest ultra took place in the heart of the Amazon jungle, and it had a staggeringly high drop-out rate.

The Jungle Marathon is probably the toughest multi-stage footrace in the world. The terrain and combination of heat and humidity make this event far more arduous than races held in desert environments. 'The Jungle Marathon: Ultra Endurance Running in the Heart of the Amazon', is the story of this epic adventure. It is about the training and preparation, the extreme physiological consequences of exercise in such a climate, and what it is to race in one of the world's most extraordinary and incredible environments.

As with the other books in the in extremis series, I describe, as best I can, the details of training for, and competition in, the toughest multi-stage footrace in the world. There is an in-depth scientific review, focussing on hydration and exercise in hot and humid climates. An extensive appendix includes tips and suggestions for race clothing and equipment, as well as resources for where to obtain further information.

The Jungle Marathon is available from Amazon and Barnes and Noble

Excerpt: Back to the Jungle

Onboard the boat I found some space on the starboard side and prepared my hammock, the ropes having to be crossed over the ropes of other hammocks as we all took whatever room was available. It was during this process that my old friend John appeared at my shoulder to greet me, beaming grin and all. I was shocked t see him for a moment. I knew that he could meet me on the boat; we had been discussing this race and its build-up via texts, emails, Facebook and Skype for months. Somehow, in becoming so absorbed with getting myself to the boat and sorting my kit, it simply struck me as absurd that any friend from the real world should be with me on a boat in the Amazon. The amazement passed and reality returned; we shook hands and exchanged manly hugs and banter as I made myself at home. John had flown out from Dubai earlier, and had been one of the first on the boat and so was nicely settled in already. We chatted until we were defeated by our need to sleep, although in truth the battle had lasted only minutes, and we duly retired to our hammocks for the night.


As the boat set off along the Rio Tapajos I felt bafflingly calm. I enjoyed the warm night's air, the humidity, and the gentle rocking of the boat as I drifted off to sleep. I was overjoyed to see John again after many months of us being in different countries, and I carried a wondrous excitement for the race ahead. I knew that I could do this; I knew that I would not be fast enough to win, not by any means, but I knew that I could manage myself well in the environment and carry myself across the distances required. 


My only concern, in all actuality, pertained to my health. As the physiologist it was expected that I could not fall ill through dehydration, because I apparently knew so much about it. But, as I could only tell myself at the time, one can never know how the body will respond to endurance exercise in such a hot and humid climate (or certainly not without experience). My previous visit involved mostly walking whilst rationing water. This time I fully intended to push myself to the limit.  If I collapsed due to heat exhaustion, dehydration or hyponatraemia, then I would never hear the end of it.  Such concerns could only be managed, however, during the din of the battle. Education aside, the rest was a matter of awareness of how my body would respond to food and fluid intake, during exercise in the jungle environment.  Such matters would be tested in the jungle, and for now all I could do was relax in my cradle as the boat rocked me to sleep.


I awoke, predictably, following the sunrise in the early morning. I tried to hide from it but as others began moving around I had found myself encouraged to do likewise. I headed off to a lower deck for a breakfast of eggs, fresh fruit and a coffee, which I then enjoyed on the upper deck in the morning sunshine. As the sun reached higher into the cloudless blue sky the temperature soared. Men that were happy to be topless for a few hours soon had their t-shirts draped across their shoulders. Hats and sunglasses were on, and the suntan lotion was out. The upper deck carried a slight breeze, as well as the pleasure of the sun, whereas the lower decks were darker, slightly cooler, yet without the breeze. There was such a hustle and bustle down there; so little space with people moving everywhere, that I capitalised on time on the top deck, only retreating below when I needed to cool off in the shade. 


Beneath a small canopy that offered marginal shade on the top deck sat a team of athletes from Guernsey. Julian had rallied the support of several of his staff at Schroders (current and former), and here they all were, doing their best to do what we were all doubtless attempting to do; to not think about what we had gotten ourselves into. The whole team were in visibly high spirits, as Julian presided over what might have been his flock, exuding a palpable confidence that spread amongst them and either filled them with motivation or dread. It was far too early for me to see anything through the smiles and laughter, but I had a feeling that if Julian was going to finish, then the rest of them were going to be finishing too. In coming here they were raising in the region of £115,000 for Headway Guernsey and the Rainbow Trust. John, Anthony, Nick, Brian, and Michael, along with their illustrious leader, had been training for about a year for this race, building up to around a hundred kilometres a week of running. Not too bad at all, considering Julian was the only one with ultra-marathon running experience. Brave, brave men; such little experience combined with the stress of all those sponsors and their boss. At least if I buggered up the race I could just skulk off and nobody but me would know.  In any case, they were maintaining a brilliantly positive perspective on their ambitions, and I found myself envious of their shared camaraderie and common ground. 


Just before midday the boat came to a stop, and some of us took immeasurable delight in hurling ourselves overboard and into the cool waters of the Rio Tapajos. The waves were calm yet a fairly strong current persisted; we had to work respectably hard simply to remain alongside the boat. Still, the bliss of cooling off in the river, even if some effort was required, was wonderful. We climbed back aboard before we had allowed ourselves to work too hard.


The boat continued to the shore of Itapuama and we disembarked onto the beach and progressed to the huts. This was the same as before; the army took the hut at the back on the left side, whilst the majority of athletes headed to the hut to the right. John and I headed left to a third hut, and tied our hammocks up there. Angus, joining us from Australia as part of the support team, tied his hammock up adjacent to ours.


I was wearing my Karrimor sandals at this time, and was less than pleased with my reintroduction to fire ants. They teemed everywhere, but appeared only to bite if the skin conditions were right, due to particular combinations of temperature, natural oils and sweat, presumably. I suggested this because neither Gus nor John was affected at first, whilst the little bastards were eating me alive. Perhaps they had just been missing me. I recalled meeting with these during my first visit, and one does become desensitised after a while to the myriad species vying for some flesh and the opportunity to cause irritation.


We had just about made ourselves at home, when the time came to untie our hammocks and take all of our food, medical and survival equipment over to the administration/dining hut for kit checks. We collected our race numbers and route books at the same time. That completed we tied our hammocks up again and John and I went off for a stroll along the beach. The afternoon temperature was dropping and grey clouds had hidden the blue sky. Further on, black clouds were looming and the sound of thunder from some miles away across the river threatened a downpour soon. It is the rainforest, I reflect; they do happen.

The Jungle Marathon is available from Amazon and Barnes and Noble

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