Metabolic Adaptations to Short-term High-Intensity Interval Training: A Little Pain For a Lot of Gain?
Martin J. Gibala and Sean L. McGee
Conclusions: As little as six sessions of high-intensity intervals over 2 weeks for a total of only approximately 15 minutes of very intense exercise can increase skeletal muscle oxidative capacity and endurance performance and later metabolic control during aerobic-based exercise.
IN PLAIN ENGLISH: Working very intensely (i.e., :30 on/:30 off for 15:00) offers comparable results to traditional endurance training (i.e., 45 minutes at a steady, but slower pace). This can make training more time-efficient.