This is the title of an article by Alex Hutchinson in his column “sweat science” in Outside Magazine. He looked at recent research on how different types of training contribute to improving our aerobic output. The bottom line appears to be that longer more moderate efforts, like brisk walking or slower running, cause more “central adaptations” like improving your heart’s pumping capacity. Shorter more intense efforts, like sprint intervals, cause more “peripheral adaptations”, like improving the ability of your muscles to take up oxygen. So overall the ideal type of training is- both. Years ago I remember Clarence Bass commenting that “I walk and I sprint, I don’t do anything in between”. It seems like he was onto something.
Following Clarence’s lead, I do mostly easier efforts at what I consider a “brisk but comfortable pace”, such as biking or hiking. A couple of times a week I throw in 8×30 second intervals at what feels like sprint pace to me. At my age, I’m not sure it looks like sprinting to passersby, but I am doing my best These latest research findings make me feel good about the effectiveness of this combination. It’s also fun and allows plenty of recovery in between hard efforts.
Rosenblat, M, et al, “Effect of Interval Training on the Factors Influencing Maximal Oxygen Consumption: A Systematic Review and Meta-Analysis”, Sports Medicine, 2022. Online HereMacpherson, R, et al, “Run sprint interval training improves aerobic performance but not maximal cardiac output”, Med Sci Sports Exerc, 2011. Online HereBostad, W, et al, “Twelve weeks of sprint interval training increases peak cardiac output in previously untrained individuals”, Eur J Appl Physiol, 2021. Online Here