Researchers at the Manchester Metropolitan University found that the metabolic cost for modern ski models is about 2.5 J/kg*m as compared to about 5 J/kg*m for ski models dated 542 AD. They also estimated maximum cross country speed for the 542 AD ski to 5 m/s, compared to about 12 m/s for modern cross country skis; for long distance skiing (several hours) results were 3 and 7 m/s respectively. This corresponds to about 5 hours for the original 1206 AD Birkebeiner flight.
The Birkebeinerrennet run has been held since 1932, and commemorates a trip made by the Birkebeiner loyalists to save the infant pretender to the Norwegian throne, Håkon Håkonsson, in 1206. All participants carry a backpack weighing at least 3.5 kg, symbolizing the weight of the then-one-year-old king.
In 2007, the race was cancelled due to extremely high winds (90 km/h or 55 mph). However, at the time of cancellation, the event had been under way for nearly an hour, with roughly a quarter of the 13,000 competitors already on course. Despite the efforts of officials to send everyone back to the start, 55 hard-nosed Norwegians eventually reached the finish in Lillehammer, and upon being interviewed, blasted the decision to cancel the event .
The race has also been cancelled in 2014 15 minutes before the start also due to "high" winds of 15 m/s . But despite of the cancellation, thousands of skiers completed the route from Rena to Lillehammer (and from Lillehammer to Rena) and blasted the decision  . Also the organizers decided not to give any refund, so the Norwegian Skiing Federation started an investigation for this case.
Special 2002 FIS World-Cup Race
In 2002, the race was included as the last event in the FIS world-cup. The world-cup class was won by Thomas Alsgaard and Anita Moen Guidon finishing in 2:24:08.7 and 2:43:39.1, respectively, faster than both Rezac's and Hilde GP's records as of 2008. The participants in the world-cup class were, however, not required to carry the 3.5 kg backpack.
Media related to Birkebeinerrennet at Wikimedia Commons
- KMZ file tracing out the route of the race Requires Google Earth software.
- 2D View in Google Maps.
- Official homepage (in Norwegian)
- English version of the official homepage
- German version of the official homepage
- Formenti, Federico et al. (2005): Human locomotion on snow: Determinants of economy and speed of skiing across the ages, Proceedings of the Royal Society B, vol. 272 no. 1572, 1561-1569 .
- FIS-Ski Results Lillehammer 2002, Men
- FIS-Ski Results Lillehammer 2002, Woman