Speed and interval training are essential parts of a skier’s training regimen, but research evidence on this topic primarily focuses on group-level differences between intervals and steady-state exercises. However, there is limited practical research on the individual suitability of intervals versus steady-state training. High-Intensity Interval Training (HIIT) versus steady-state training in the aerobic threshold (VT1) range is a well-researched topic at the group level, and according to Vesterinen, differences have been found.

“High-intensity interval training is more effective when it comes to improving maximal oxygen uptake and performance. Studies have also shown significant individual variation in the response to high-intensity training. Some individuals see little improvement, while others see significant progress. The reasons behind these differences are not well understood. We would need more information to determine whether someone improves better with steady-state training or intervals,” Vesterinen explains to Maastohiihto.com.

In his doctoral thesis, Vesterinen specifically studied individual variations in the effectiveness of endurance training. The study compared the differences between volume-based low-intensity training and high-intensity training on an individual level. In both groups, individuals who showed both significant improvement and limited improvement were found.

“High-intensity training primarily enhances maximum oxygen uptake and maximal performance capabilities. When we looked at the factors explaining development in endurance athletes, we found that age or fitness level were not linked to improvement. The strongest explanatory factor was resting heart rate variability. Those who benefited most from high-intensity interval training had higher heart rate variability. On the other hand, those who benefited from low-intensity training had lower heart rate variability. For them, low-intensity training was sufficient to provide a training stimulus, and they didn’t benefit as much from high-intensity training, which can be overly taxing,” says Vesterinen.

In high-intensity intervals, it’s possible to sustain higher intensities for longer periods due to recovery intervals. This makes it easier to improve maximal performance compared to steady-state exercises. In sports that involve interval-like activities and fast-paced efforts, improving performance is easier with intervals than with steady-state workouts.

“Steady-state training is more suitable for athletes preparing for long-duration events like marathons or long-distance mass skiing,” Vesterinen adds. “For recreational athletes, steady-state training is often a form of aerobic threshold training, while more highly conditioned individuals may require high-intensity interval workouts.”

Short Intervals for Modern Skiing

Recent Norwegian studies have compared short intervals to traditional longer intervals.

“It’s often been observed that 3-5-minute high-intensity intervals are the most effective for eliciting a training response. However, newer research has looked at short 30-second intervals. For example, 3x13x30 seconds with a 15-second recovery can produce an even better response. With these shorter intervals, you can maintain higher intensity levels, and oxygen consumption doesn’t have time to drop during the recoveries. One of the key factors for developing maximal oxygen uptake is to keep oxygen consumption close to the maximum for as long as possible during the workout,” Vesterinen notes.

This topic is closely related to recent discussions in Finnish cross-country skiing, focusing on the need for greater speed.

“Shorter intervals serve this purpose better when training at higher intensities. Skiing is a sport where shorter intervals can provide more readiness for short bursts of effort, even when you are relatively fatigued. This helps prevent the accumulation of oxygen debt during sprints,” Vesterinen explains.

In Finland, traditional endurance training programs have included mostly aerobic training (PK), followed by threshold training (VT2), and then high-intensity training (VT1). In contrast, polarized training, which focuses mainly on aerobic training (PK) and high-intensity training (VT1), is more common in Norway.

“Research also supports the idea that polarized training is slightly more effective. For high-intensity workouts, shorter intervals may become more common. They allow for even higher speeds,” Vesterinen concludes.

This article was originally published on February 6, 2020.

Training perspectives for speed and interval training in skiing may change with the development of the sport, and Maastohiihto.com regularly publishes training-related articles based on research. For more information on training, you can read articles in English on the ProXCskiing.com website.