Obstacle Difficulty: In Search Of The Sweet Spot

When is an obstacle just difficult enough, but not too difficult?

I have been thinking about this question a lot recently. One of the great things about OCR is that it appeals to participants at all ends of the fitness spectrum: there are countless stories of people whose first foray off the couch is a Warrior Dash that they got dragged to by a co-worker, and there are athletes whose fitness levels match those of the top-ranked men and women in any sport. The courses that designers create must provide a good experience for everyone who attempts them. How do you make sure that the array of obstacles is a good match for the broadest possible market? And what happens when you don’t?

The first time I noticed this problem was when I tackled the Spartan Sprint at Tuxedo in June.  I went with some instructors from my neighborhood CrossFit box, who had never done a Spartan Race of any distance. After climbing up the mountain and down the mountain and up the mountain and down the mountain on a hot summer afternoon, they were exhausted. Again, these were people who are among the fittest around; there is also supposed to be a good match between CrossFit skills and what is needed to succeed at Spartan Races (and not just because both are sponsored by Reebok). Nevertheless, they found the Sprint distance to be daunting enough that they weren’t going to try it again. I found myself closer to the back of the pack during the race, and I spoke with plenty of people who were overwhelmed with how difficult the course was. Some were novices, and some were racers who had tried the stadium sprint at CitiField a few months prior. If a Sprint distance race, which is presumably the entry-level event for this series, left so many participants gassed and burpeeing out of obstacles, how was Spartan going to appeal to the masses it hopes to convert to its way of life?

Another Spartan Race brought this issue to mind, this time in Asheville. Followers of ORM will remember the time when Ryan Atkins, one of the most successful athletes in the sport, found himself unable to climb a rope because it was too slippery. As he later said in an interview, if it was too difficult even for him, how could anyone else be expected to succeed at that obstacle? For the record, I should point out that because Ryan is Canadian, when he said it he made it sound modest and not at all obnoxious as it might seem out of context.


Ryan Atkins has a 100% completion rate for this obstacle

Finally, I read about another race series that bragged about how difficult its obstacles are, which sounds like decent marketing. However, this race also featured mandatory obstacle completion, which is to say that you were not eligible for a spot on the podium unless you completed all the obstacles (i.e, no option for taking a penalty like burpees and continuing with the race). The result was that a number of the age-group podiums lacked anyone who made it to the finish line without failing at least one obstacle.

There must be some kind of sweet spot: a level of difficulty between there being no obstacles at all (a 5K trail run, for example) and where the obstacles are impossible to complete. Somewhere in the middle there must be a level of difficulty that challenges people new to the sport but still makes the experience competitive for those who are hoping to win, easy enough that racers can get through the obstacles but not so easy that the experience is boring. Is this something that race directors think about? How do they balance those needs?

I spoke to Garfield Griffiths, who has designed obstacles for Savage Race, BattleFrog, OCRWC and, most recently, CMC. He is a fan of mandatory completion, though he sees that it can lead to problems and empty slots on the podium. As he put it, “how many 70 year olds can complete Sawtooth?” Races need to appeal broadly, and he is more about people being able to do the obstacles. “A 70% success rate is a decent rate to shoot for.” For example, at the OCR World Championships, he thinks that 70% would be the right level for an designer to strive for, and that there is not much point in making an obstacle so difficult that even Ryan Atkins can’t complete it. He also noted that a world championship event can have the same level of difficulty as a less famous event. The Olympic marathon is just as difficult and just as long as the marathon in your home town, so the obstacles at OCRWC should be just as difficult as at a locally run competitive race. A less competitive event, such as a Rugged Maniac, might shoot for a higher rate, perhaps 80%. He also noted that there are different success rates for different types of obstacles; a showcase obstacle might be designed to have a success rate of 65 to 70 percent, whereas for a harder obstacle such as monkey bars the rate might dip to 60%. Of course, this is balanced by other obstacles where failure isn’t really an issue. “You can’t really fail at a mud crawl.” Finally, he pointed out that “you need people to come back”. If the obstacles are so daunting and discouraging, eventually you lose customers.


Garfield Griffiths, right, mugging for the camera

Saw Tooth

Sawtooth. Not easy, especially for a 70 year-old.

I also spoke to Eli Hutchison from Tough Mudder, whose official title is Senior Product Manager, but who might be better known as one of the designers of Tough Mudder’s brilliant range of obstacles. Indeed, he told me that there is a sweet spot for every obstacle, though since Tough Mudder is “a challenge, not a race”, the reasons for selecting that sweet spot are different from those of other events. He opened the (I’ll assume orange-colored) kimono as to how TMHQ selects their obstacles and adjusts their difficulty. For starters, Tough Mudder divides obstacles into four categories, depending on its goal:
1) Fun, such as Mud Mile.
2) Personal accomplishment. An obstacle such as Funky Monkey, requires upper body strength, which comes with training and developing skills.
3) Courage (“Mental Grit”). Obstacles such as Arctic Enema and Electroshock Therapy require participants to overcome fears, but they do not require any physical skills.
4) Teamwork. Generally these obstacles require that you cooperate with other people on the course, though there are some that, if you are a top athlete, you could also complete on your own, such as Everest 2.0. However, these obstacles are all totally achievable if you work together.


Eli, right, poses with fellow Tough Mudder Evil Genius, Nolan Kombol

For the personal accomplishment obstacles, the designers set a goal for how many can complete the obstacle. The rate varies from obstacle to obstacle, but most hover around 60% in dry ideal conditions. For King of the Swingers, about one out of every three participants succeedes in hitting the bell, a rate that TMHQ achieved by adjusting the distance to the bell until they got that rate. Why so low? King of the Swingers, and its level of difficulty, keeps people wanting to come back and try it again until they get it right and attain that level of personal achievement. How does TMHQ figure this out? You know those customer satisfaction surveys they send out? They actually read them and tabulate the results. This should not surprise anyone who remembers Tough Mudder’s origin story as a business school project. King of the Swingers received the highest score when the bell was set at a distance where one in three could hit the bell. Part of the experience that Tough Mudder sells is providing people with true physical challenges and giving them the opportunity to overcome them. Some of the happiest customers are those that surprised themselves.


King of the Swingers

The same number-crunching applies even for the “Mental Grit” obstacles. These are supposed to instill fear, but the fear is not supposed to be so debilitating that participants balk and cause a back-up as they hesitate to go through the electric wires or into the ice bath. TMHQ calculates the throughput, times how long people stall, and optimizes the experience. When TM introduced the Half Mudder as an entry-level event, they also made adjustments to these obstacles.

Eli also told me that these precepts are applied differently for World’s Toughest Mudder. Given the differences in the number and experience of the participants, they could adjust some obstacles to make them more difficult. When Toughest Mudder (an eight hour version of WTM) is introduced next year, they will shoot for a middle ground because the length of the event gives them more time to work with than the regular Tough Mudder.

Finally, as Tough Mudder branches out globally, they have analyzed how to apply the sweet spot to appeal to customers in different countries. For example “Australians like things to be a lot harder“, so you will find a different menu of obstacles there. Local conditions can also dictate what constitutes a tougher obstacle. As Tough Mudder moves into Asia, they have had to take into account that the percentage of people who can swim is lower than in the US. Even smaller distances can yield different results. Apparently there are 15 -20% swings in completion rates for the same obstacles in Tahoe and Vancouver.

At Spartan Races, I spoke to VP for Production Mike Morris, who told me that the relative difficulty of the obstacles was something they talk about a lot at Spartan HQ.  Their approach is different from Tough Mudder’s, because while both are concerned about safety, Spartan also prioritizes developing the sport of OCR. “The obstacles don’t have to be mind-blowingly difficult or crazy or huge. It’s not about just building the biggest monstrosity, but building and developing the sport and building a lifestyle around the sport.” They are looking to challenge the elites, but they are also looking to engage the majority of runners who are racing for fun. For the elite runners, the variety of the obstacles allows racers to leverage different strengths – a bucket carry is a good obstacle for a stronger athlete, but the monkey bars are a better obstacle for a lighter racer.
Spartan WC 2015 Byrce Stanton Bucket Carry
Bucket carry – better for some athletes than for others.
In its early years Spartan experimented with race-specific obstacles  for the races of different lengths, so you would see some obstacles only at the Sprint or only at the Super distance. For 2017 there will be more specific obstacles, ones that are unique to the Beast or unique to the Super. “People who show up for harder races are in better shape.”

Are obstacles at races too hard? Too easy? And do you seek out events depending on the level of difficulty? While no race series will be able to satisfy everyone, is there one that has the broadest appeal to you based on how tough the event is? Let us know in the comments.

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Christopher Stephens

Christopher is an attorney, a middle-of-the-pack triathlete, a marathoner, an open water swimmer, and a recovering Jeopardy contestant. A native New Yorker, he trains in the rugged wilderness of Central Park and can sometimes be found swimming in the Hudson. He also bakes pies. Delicious pies.
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