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My Go-To Hard Workout

It's quick, tough, and beneficial for anyone.

My Go-To Hard Workout

The big idea: IWT workouts are a time-tested way for anyone to get really, really fit.

Why it matters: The workout is designed to trick you into going harder. That increases your VO2 and avoids common high-intensity workout pitfalls, which improves your fitness and disease resistance.

When I was an editor at Men’s Health, I wrote a feature story on a Salt Lake City-based gym called Gym Jones. The place was founded by a celebrated mountaineer named Mark Twight.

As a climber, Twight noticed, “there were people who were fitter and better technical climbers than I was,” he told me. “But I did more transformative things because of what I had on board mentally.” He realized that once you’d trained enough, the factor that most determined your performance was sitting between your ears.

So he established Gym Jones in 2003 to help outdoor athletes “unf*ck their heads,” as he put it. For years the place existed on the fringes of hardcore fitness. But as word of the success of their athletes spread, the gym landed contracts to train elite Special Forces warfare units and MMA fighters.

Then in 2006, the movie 300 came out. The film became famous for how in shape its actors were. It turns out the actors had all trained through Gym Jones.

And it was a famously gritty gym. I wrote of the place:

In a state known for religious zeal, Gym Jones fits right in. Members are called disciples, and half-assed effort leads to excommunication. Many of the workouts—which range from crushing, hourlong circuits to vicious intervals on the rower or AirDyne—are insanely intense. “Each workout is designed to be a mental crucible, an exercise in the art of suffering,” Twight says. “Through suffering, you discover your true potential.”

The place had an energy and a sense of purpose I haven’t encountered in a gym since. No mirrors, no air conditioning. Just effort.

After I wrote the story, I kept coming back. I completed the Gym Jones Levels I and II certifications. I’d drop in anytime I was in Salt Lake City, which was often because I grew up there.

Each visit felt like walking into a viper pit. But, once you’d gone and trained enough, you started feeling like a viper yourself.

The place, however, was like one of its workouts: so intense that it could only happen for so long. It eventually fell apart. Leaders clashed and left, and OG trainees splintered.

I remember Fridays at the gym most. Friday’s workouts were “hard as hell. They set the tone for the weekend,” my friend Bobby Maximus, the gym’s GM said. He called the Friday workouts FYFs, which stood for “f*ck you Friday.” Our workout on Friday was inevitably a type of workout called an IWT.

Today we’re going to cover this style of workout, the IWT. The good news: Anyone, no matter their age or ability level, can do an IWT. They’re a uniquely great workout for improving fitness across the board—especially if you want to challenge yourself or are pressed for time.


In 1969, a competitive weightlifter and exercise scientist at Oregon State University named Pat O’Shea noticed that approaches to fitness at the time had a shortcoming. In the gym, people were told to do one of two things: standard strength weightlifting workouts or circuits using light weights.

“While (these methods) are effective in terms of maximizing improvement of a single variable,” O’Shea explained, “it is time consuming and inefficient when attempting to simultaneously train multiple variables.”

Studies showed that the strength workouts did increase strength and power. But they did so at the expense of cardio. For example, one study of weightlifters found that traditional strength and power training had the unintended side effect of decreasing VO2 max.

On the other hand, the fast-paced circuits that used lighter weights did improve VO2. But not by much. A group of men in one study improved their VO2 max by 3.5% after 20 weeks of this circuit training. Good. But not compared to a group who did a running program, which boosted their VO2 max by 17%. And those workouts also didn’t do much to improve strength and power.

To solve this, O’Shea began tinkering with a style of workout he called “interval weight training,” or IWT for short.

He spent two decades perfecting his idea. In the late 80s, he released a paper about it in the National Strength and Conditioning Association Journal.

O’Shea wrote that his IWT workouts were “an effective method of athletic cross-training for the physiological variables of strength, muscular endurance, power, and aerobic power.” He discovered that they helped his athletes become stronger and increase their VO2 max.

My friend Bobby Maximus, the Gym Jones GM, explained to me, “At first, the IWT paper attracted little attention. But somewhere along the lines Gym Jones got our hands on a copy of that paper. We followed the routine, started sharing it with athletes, and it quickly became our answer for anyone who needed to build strength, endurance, and power in as little time as possible.”

IWTs for all

O’Shea acknowledged that the workout style is tough. “(It) requires determination, motivation, and a positive self-image that physiologically all systems say go: the body is strong, powerful, and capable of coping with the intense training … when properly applied, IWT has the capacity to produce a more powerful athlete possessing a high degree of recovery fitness.”

But just because the method is hard doesn’t mean anyone can’t do it. Anyone ranging from a retiree to a professional athlete can see a benefit.

The workout should be hard for you. The point is to modify the workout to your ability and do it at a challenging intensity.

How to do an IWT

In an IWT, you do a strength exercise that works your entire body, followed by a fast-paced cardio exercise where you try to reach a goal distance. You do that for three rounds. That’s phase one.

In phase two, you repeat but with a different strength exercise and a different cardio exercise, again with a distance goal. You do that for another three rounds.

I’ve listed a few strength and cardio exercises below. Mix and match. They’re not the end-all-be-all IWT workouts, though. Feel free to make up your own IWTs using the format, subbing in different exercises.

IWT instructions

Pick one of the following strength exercises: Push press, goblet squat, deadlift, pushups, kettlebell swing, dips, pullups, bent-over rows, bench press, front squat, back squat, etc. Note: Select a weight you can do 10 reps of with good form.

Pick one of the following cardio exercises: Rowing, stair climber, treadmill, jump rope, exercise bike, elliptical, etc. Note: Select an “effort goal” you think you can hit in two minutes if you put in a lot of effort. For example, if I’m rowing, I try to reach 580 meters of distance in the two minutes. But your goal could be some number of stairs climbed on the stair climber, distance on the treadmill or bike, skips of a jump rope, calories on an elliptical, etc.

Now do the workout: Start by doing 10 reps of the strength exercise. Now immediately do two minutes of the cardio exercise. Rest two minutes. That’s one round. Do three rounds total.

Afterward, rest at least five minutes. Now repeat the exact same formula using different strength and cardio exercises.

Here’s a full example using goblet squats and push presses as the strength exercises and rowing and running as the cardio exercises.

Phase 1
1a. 10 reps of goblet squats
1b. 2 minutes of rowing, trying to reach a distance goal
Do three rounds of that, resting two minutes between rounds.

2. Rest five minutes (you’ll need it if you did Phase 1 right)

Phase 2
3a. 10 reps of push presses
3b. 2 minutes of running on a treadmill, trying to reach a distance goal
Do three rounds of that, resting two minutes between rounds

Remember: Anyone can do this workout. You just have to adapt the strength exercises and their weights and cardio distances to your fitness level. The point is to do something that packs in a lot of effort and feels hard for you.

For example, Bobby Maximus, who is an extremely fit and giant human, might squat 300 pounds for 10 reps and then try to reach 625 yards in his two minutes of rowing. But a retiree might do 10 goblet squats with 10 pounds and walk on the treadmill at 3.5 miles an hour. Both become harder to kill.

2% Top Two

My two favorite things this week ...

One: The Oatmeal Recipe

I had a lot of people email me about my oatmeal recipe from last week's email. Specifically about how vague my description of it was. Sorry. I should learn how to write. Here’s exactly what I do:

Step one: Pour two cups of dry oats, one serving of frozen berries, and ~14 ounces water into a large bowl.
Step two: Put the bowl in the microwave for 5 minutes 30 seconds.
Step three: (optional) let the bowl sit for 1 to 2 hours (remember, the beta-glucan fiber gives the oats a better texture as it cools).
Step four: Mix in between a half and full serving of peanut butter.
Step five: Mix in one serving of Momentous Plant Protein.
Step six: Sprinkle a bit of salt and sugar free maple syrup on top.
Step seven: Eat
Step eight: (Maybe) do an IWT

All in all, the breakfast—which you can modify to your own needs—has: -950 calories -53 grams of protein -26 grams of fat -135 carbohydrates

Two: 5/1/23

We have a big announcement landing in your inbox that day.

Thanks for reading. Have fun, don't die.


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