Michael Drozd (MSF bio here) of the Czech Republic had a lengthy professional marathon swimming career from 1993 to 2000. He competed in over 30 races, including racing at the European Championships and World Championships.
There was a one-week period of his career when Drozd was on fire, winning both the Traversée internationale du lac St-Jean and the Traversée Internationale du lac Memphrémagog, both held in the end of July 1997 – the only two professional victories of his long career.
During the 40 km Traversée internationale du lac St-Jean race, a special research project by Suzanne Leclerc, MD, Vincent Lacroix, MD, nd David Montgomery, PhD resulted in a published paper, Body temperature homeostasis during a 40 km open water swim.
The purpose of the study was to monitor body temperatures of the swimmers by a capsule (thermometer pill swallowed 2 hours prior to the race start) with a temperature sensitive quartz crystal that transmitted a signal to a remote receiver.
The results showed that while there was a mean temperature decrease of 2.0°C (both orally in the mouth and tympanically in the ear) among the swimmers from pre-swim to post-swim, the mean core temperature difference pre- and post-swim was relatively minor – from 37.5°C (99.5°F) to 37.3°C (99.1°F).
The researchers concluded that the swimmers were able to maintain their core body temperatures during the marathon swim, and very importantly, oral or tympanic (ear) temperature measurements may not accurately reflect a swimmer’s core body temperature.
While there have been many years when swimmers have been pulled from the Traversée internationale du lac St-Jean due to hypothermia, in the 1997 race, the water temperatures were on the warm side. The start of the race in Péribonka was in an inflowing river where the swimmers competed 4.11 km in 18.3°C water. The next 35.89 km of the race that ended in Roberval (see map below) was held in the lake where the mean temperature was 21.9°C while the air temperature was 23°C – a remarkably nice day on lac St-Jean despite the stiff winds that ranged between 20 and 40 kph.
1997 Traversée internationale du lac St-Jean Results
- Michael Drozd, Czech Republic 9:28:33
- Alexandre Leduc, Canada 9:41:02
- Fernando Terrilli, Argentina 9:54:03
- Jean-François Roussy, Canada 10:02:00
- Mohamed Marouf, Egypt 10:4:57
- Khaled El Saidy, Egypt 10:10:38
- Ahmed El Ghitany, Egypt 10:12:25
- Karen Burton Reeder, USA 10:17:06
- Nathalie Sauvageau, Canada 10:44:01
- Igor de Souza, Brazil 10:49:06
- Ramy Maher Abd El-Wahab, Egypt 10:50:24
- Sébastien Bolduc, Canada 10:54:24
- Kathrin Lammers, Germany 11:04:13
- Claudio Plit, Argentina 11:11:32
- Mohamed Salah El-Din Morsy, Egypt 11:13:43
- Irene van der Laan, Netherlands 11:20:27
- Maria Fernanda Moreno, Argentina 11:43:28
- Ahmed Abdalla, Egypt 11:37:18
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