How effective can a set of short-term sprint intervals compared to regular endurance training at a comfortable pace be? It is well known that interval training can be time-saving, but in July 2006, a fascinating study was published in The Journal of Physiology. The scientists compared the outcome of low volume sprint training three times a week (4-6 x (30sec. all-out efforts / 4 min. recovery)) with high volume endurance training three times a week (90-120min at 65% VO2 peak).
Before starting the training programs, the riders performed a 2km and 30km time trial. Then, after the 14-days training program, they did the same tests repeatedly. In addition, muscle samples were taken to show molecular and cellular adaptations.
Both groups had similar increments in oxidative muscle capacity, muscle buffering capacity, and glycogen content. These increments were significant, showing us that the initial adaptations seem to be the same, whether you go for short intervals or long rides. The exciting part is that the sprint group spent much less time on their training but got the same improvements in performance. They only spent 7-8 minutes a week on their intervals (and 60 minutes recovery time). On the other hand, the endurance group rode their bikes for more than 5 hours a week!
This report is fascinating, and I look forward to reading more results from these scientists. In the future, I will prefer a setup with trained cyclists instead of just ‘active men’ and let them stick to the training program for a more extended time. Nevertheless, this study shows how deep impact intervals can make on performance.
I’ll go for some high-intensity sprints on my Principia this afternoon.
Gibala MJ, Little JP, van Essen M, Wilkin GP, Burgomaster KA, Safdar A, Raha
S, Tarnopolsky MA. Short-term sprint interval versus traditional endurance training: Similar initial adaptations in human skeletal muscle and exercise performance. J Physiol. 2006 Jul 6;