Skisens spent this past weekend at two exciting roller ski races — Allum Hill Race on Saturday and Topprullen on Sunday. We witnessed strong performances, fast racing, and had the chance to meet many passionate roller skiers and coaches.
Power Output Analysis from Allum Hill Race
Allum Hill Race is a pure uphill roller ski race, making it ideal for performance analysis. Several athletes raced using Skisens power-measuring ski poles, allowing us to calculate the rolling resistance on the race course.
Based on our measurements, winners Linnea Johansson and Markus Johansson achieved impressive power outputs of 4.1 W/kg and 4.0 W/kg over roughly 10 and 12 minutes. Figure 1 compares these values to our empirical power profiles and previous Strava records. We also noted that Linnea improved her wattage compared to last year, while Herman Paus delivered 4.2 W/kg in last year’s race. Markus himself skied slightly faster this year as well. Conditions were similar both years, and we used the same rolling resistance assumptions. On average, returning athletes skied faster this year.
Power records with Allum Hill Race winners plotted.
Measuring Rolling Resistance on Roller Ski Wheels
At Allum Hill Race we also met Andreas and Albert from Chalmers, who have developed a measurement instrument for testing rolling resistance on roller ski wheels. Their measurements revealed the rolling resistance of Lager 157’s SKIGO loan skis used during the race.
The results showed that the wheels used in the competition were consistent down to the third decimal place. The maximum potential impact on race results was estimated to be around 10 seconds over 3.5 km — likely smaller than typical variation between skis on snow.
Wheel Differences Can Impact Roller Ski Race Results
Competitors and visitors were also able to test their own wheels. We observed that rubber “2” wheels from other brands could vary by up to ±15% in rolling resistance compared to SKIGO’s wheels. Meanwhile, Skimateria’s blue PU wheels were measured to have more than 30% lower resistance than SKIGO’s 2s — a difference with direct race implications.
Over a 3.5 km race, this resistance difference translates to roughly one minute for an average skier — demonstrating how wheel choice can dramatically influence roller ski performance.
How Temperature Affects Roller Ski Wheels
Another significant factor was temperature sensitivity. The blue PU wheels were among the most temperature-stable, providing consistent conditions for both light and heavy skiers. ELPEX red PU wheels showed high friction when cold but nearly matched the blue wheels once warmed up. The table below shows race times and calculated W/kg for athletes using SKIGO loan skis, along with equivalent times for blue PU wheels and yellow PU race wheels based on measured rolling resistance.
Race time on SKIGO 2s, W/kg, and adjusted times for other wheel types.
Historical Comparison and Performance Benchmarks
An interesting takeaway from Table 1 is that Markus Johansson’s time would correspond to 9:07 on yellow race wheels — nearly identical to the fastest recorded time from 10 years ago on similar wheels. Digging into historical results, we also found that Karl-Johan Westberg raced the course in 8:09 in freestyle. Converted to W/kg, this performance approaches 4.8 W/kg, which is exceptionally strong relative to our empirical power profiles.
Huge thanks to Topprullen, Allum, and Sävedalens AIK for fantastic roller ski races and a great weekend of performance data and insights!
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