Saying doing 1 set to failure on 12 Nautilus machines is better than doing body weight and running in gaining cardio vascular endurance is outrageous.
Researchers from the St. John's Hospital in Minnesota combined with Arizona State University as reported in 1985 April issue of "The Physician and Sports Medicine" did a research study. They used a Nautilus circuit of 14 exercises. They had the subjects move from one machine to another with as little rest as they could push the subjects. 8 to 12 reps for upper body and 8-20 lower body. While the men subjects (leaving the women out for typing sake) maintained an average heart rate of 139.9 BPM. Here's the thing with anaerobic exercise. The mean oxygen uptake was only 35.9%. It wasn't close to the recommended minimum of 50-75% of VO2 maximum recommended by the American College of Sports Medicine for aerobic exercise.
Calories used was also low 113 for the Nautilus session for the women and 171 for the men. A slow 2 mile run exceeds that.
The reason why a Nautilus session isn't a good aerobic trainer is that one exercise doesn't last long enough to make demands on the aerobic system. An elevated heart rate isn't proof in it self of training the aerobic system.
Another reason is while each exercise lasted 60 to 90 seconds the next exercise moved to a different body part. The aerobic mechanism in each body part wasn't worked long enough for an aerobic training effect.
I could go on but I just came back from my Yates inspired one set to failure routine followed by a hard 3 mile run in 91 degree humidity. Feeling shot. LOL.
I was a boxer too. Turns out after being 4-1 I didn't like getting hit in the face. That's why I'm still pretty.
