Can 4 Seconds of Exercise Make a difference?

In a recent article in the New York Times titled “Can 4 Seconds of Exercise Make a Difference?” by Gretchen Reynolds, discussing a study by Ed Coyle. It discussed the use of high-intensity interval training (HIIT) using 4-second intervals, repeated until they amounted to a minute of total exertion as a method of improving strength and fitness in older adults, and in fact, it stated rapid improvements in strength and fitness in middle-aged and older adults.

I am a strong proponent of HIIT and HIT training, but here I would like to mention some of the shortcomings of the article.

• The headline is misleading, asking whether only 4 seconds of exercise can make a difference. The actual exercise involved 4-second bursts of maximum activity for a total of 1 minute. So, in other words, 15 sets of 4-second intensive activity, followed by 56 seconds of rest. Therefore, the impact of 15 minutes of exercise is being measured, not 4 seconds. In other words, the subjects performed fifteen 60-second intervals.

• Over the two-month study period, the rest periods decreased to 26 seconds, increasing the total number of intervals to 30 4-second over the 15 minute period.

• No footnotes or references are provided by the NYT. There was a link to the Medicine & Science in Sports & Exercise (MSSE) journal in the original article that has been removed since, but it leads to an unknown page on their website.

• Searching the MSSE Journal's website, Pubmed, and Google Scholar did not reveal the study either. I could only find one article on the MSSE website, with Coyle as co-author. This was a pilot study about 4 seconds of exercise done hourly to break up prolonged sitting.
  
  Wolfe AS, Burton HM, Vardarli E, Coyle EF. Hourly 4-s Sprints Prevent Impairment of Postprandial Fat Metabolism from Inactivity. Med Sci Sports Exerc. 2020;52(10):2262-2269. doi:10.1249/MSS.0000000000002367
  
  This prior pilot study of a handful of college studies is interesting, but the results are notable for their lack of significance. The data trend was toward the reported results, but since it did not reach statistical significance, it was not relevant.

• The equipment used in the study to perform the intervals were the lab’s specialized bikes. There is a conflict of interest with Dr. Coyle having equity in the company that manufactures the bicycles. Dr. Coyle states that this monetary involvement does not affect research results from his lab.

As I mentioned before, I am all about HIIT and HIT, but this article, and especially the title, is misleading and not based on appropriate, peer-reviewed data.
The question in my mind: can we eventually get down to a Zero-Second exercise routine?

See NYTimes, December 30, 2020