Dorian Yates’ way of training hasn’t changed since hoisting the Sandow trophy into the air. On Nov. 19, 2025, he broke down ‘The Colorado Experiment,’ which saw Casey Viator gain 63 pounds in just 28 days, proving that science-based high-intensity training works.
The study featured the late Arthur Jones and Casey Viator as its subjects. Jones invented the Nautilus machines and redefined how bodybuilders approached training. Though performing a fixed number of sets and reps was the norm, Jones challenged this idea.
Instead, he argued the ‘less is more’ philosophy. Jones was adamant that achieving failure was more important than time spent at the gym. This system was later adopted and then manipulated by Dorian Yates, who leveraged it to become a six-time Mr. Olympia. While science-based lifting changed how athletes work out today, Yates believes that his training system has always been supported by evidence.
“A lot of you younger guys may not have heard of Arthur Jones, in short he invented the Nautilus line of gym equipment and challenged the common belief that you need to spend hours upon hours training each day.”
Yates Shows How HIT & The Colorado Experiment Prove Max Growth With Minimal Volume
In the post, Yates explained The Colorado Experiment from 1973.
“Science based training…
Well my question is; what is this science, where is the data coming from, which studies are they, how were they conducted, who were the participants?
I do know of one experiment that was conducted and documented back in May 1973… The Colorado Experiment, by Arthur Jones.”
Jones and Viator were the subjects in the study. After three 34-minute, intense failure-based sessions in four weeks, Viator gained a staggering 63 pounds.
“The location was Colorado State University and was supervised by Dr. Elliott Plese, Director of Exercise Physiology Lab at Colorado State University. Both Arthur and Casey Viator (a bodybuilder and youngest Mr. America) were the participants. Jones put Casey through a series of brief, but super intense workouts to failure, that averaged 34 minutes roughly 3x per week.”
“It’s documented that Casey’s overall muscle mass gain in the 28 days of the experiment was 63lbs!
Now I want to mention and this is important, that this was old muscle that he had lost due to weight loss mainly from an accident and from an allergic reaction.”
To drive home the value of his HIT approach, Yates noted that it took Arnold Schwarzenegger four months to pack on 15 pounds for the 1975 Mr. Olympia.
“A comparison I want to make is that since we are comparing muscle memory; Arnold lost weight for the movie ‘Stay Hungry’ in 1975, to weigh 210lbs. He then trained for roughly 3-4 months, sometimes twice per day, to weigh I believe 225lbs at that year’s Olympia, so that’s 15lbs in a 4 month period and Casey regained 63lbs in a month.”
“Obviously the average person is not going to gain 63lbs in a month, and yes I believe both guys were using gear, but my point is that you do not need a lot of volume to stimulate growth.”
“The Shadow” urged lifters to ditch hours of volume and focus on overload, stress, intensity, and pushing yourself to failure.
“You do not need to be spending hours doing volume; it’s about overload, stress, intensity and pushing yourself to the absolute limit.
Of course with sufficient nutrition and recovery too. But HIT in my opinion is the fastest and most effective way of putting on muscle mass and I believe Viator proved this,” Dorian Yates shared.
In addition to Yates, rising IFBB Pro Sam Sulek discussed the validity of science-based lifting. He called it a “snakeoil of an idea” rather than a legitimate product. He added, “For a younger guy, it’s this clout mentality of oh, I’m on the new wave train — some of it is a little silly. I don’t think all of it is.”
While some have doubted Yates’ training principles, the studies back it up. He believes effort and reaching failure are crucial to adding muscle and size as a bodybuilder.
RELATED: Dorian Yates Not a Fan of ‘Reps in Reserve’: “It’s Called a Wanker’s Workout”
My opinion? The only true way to test or prove the validity of any training method is to test it on clean, all natural subjects. When you’re on the juice, just about anything you do works exponentially. It’s not a true, base level test, so you won’t get true base level results. Unless, of course, we’re resigned to the idea that in our modern age muscle is only built on gear. The results from “experiments” & systems like HIT don’t represent real world gains for the naturally trained athlete. The natural trainee’s body doesn’t respond to exercise the way the body on gear does because of the hormonal atmosphere and recovery limitations. It simply does not. You must train differently –
What would be the best training routine for a 61 year old man for this type of training?
Please correct this article and give Mike Mentzer due credit as Dorian Yates was one of his clients in the H.I.T. muscle building system. Please do your research. I too was Mentzer’s client. Mr. Mentzer had a perfect 300 score for Mr. Universe no one else achieved that score to my knowledge. Mr. Mentzer wrote books on thie H.I.T training system in your article. It was him and Arthur Jones who founded and created it, not Dorian Yates.
Thank you.
Isn’t this the same training method that Mike Mentzer proclaimed was the absolute best? One set of each exercise to absolute failure with seven days off for recovery.
The Colorado experiment was actually a hoax. Results were falsified, Viator was on steroids. The experiment has never been replicated. Jones later tried to do it with Boyer Coe and it fizzled, despite Coe having lost weight before the experiment in order to make the results look better.
My question is can someone not using gear gain that much weight by using the Yates method??
First of all… 63lbs of muscle is a lot!!! Casey looks 20lbs heavier!!! If that!!!!!