Found this in an article, sharing here as it pertains to similar flow of 4 minute drills.
“A study in Cell Metabolism found that four 4 minute bursts of flat out exercise on a stationary bicycle just three days a week – a total of just 48 high intensity minutes a week – resulted in much greater levels of age-reversing changes at the genetic and cellular levels, along with enhanced mitochondrial activity, and improved insulin sensitivity than regular weight lifting sessions.”
Looking at high intensity, you would have to do sprints on the stationary bike, likely 10 seconds full speed with some higher resistance, then 10 seconds steady state. Would have been nice if the article specified this.
I have taught 4×4’s in my warm ups for students with great results.