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The best way to test the reliability of an information source is to see what it says about a topic you’re knowledgeable about. If what it says is reasonably in line with what you know to be true, good; if it’s wrong in that area, then it probably will be wrong about topics you don’t know about, and you probably should ignore it.
It was in that spirit that I recently spent hours talking about running with ChatGPT, the best-known generative artificial intelligence (AI) bot. How well would it answer basic running questions? How accurately would it relay factual matters? Does it deserve to put publications like Runner’s World out of business?
Executive summary: Some of its answers were in line with current best practices, and no better or worse than much of what you can find online written by humans. But, as you’ll see, sometimes it was alarmingly incorrect, a problem made worse by the certainty and specificity of its answers. One oddity of my time with ChatGPT was how often it was wrong about basic facts, which in my AI ignorance I assumed would be where it would perform best.
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Here’s a look at my running talk with the bot. In transcripts, my prompts are in bold, the bot’s responses in italics.
Off to a Good Start
ChatGPT’s answers to some common running questions were accurate, thorough, and concise.
When I asked, “Should I stretch before I run?” it correctly responded that experts recommend a dynamic warmup (leg swings, lunges, etc.) instead of static stretching, but that static stretching can be useful after your run.
When I asked, “Why does running put me in a better mood?” it gave a brief, accurate explanation of endorphins and other feel-good brain chemicals that running can spur the release of. It also mentioned running as a time away from stressful activities of daily life, and even made an important psychological point about seeing yourself achieve goals. Its answers to questions about running and osteoarthritis, caffeine, foot strike, running cadence, and shoe selection were also on par with basic, accurate human-written articles.
But there were oddities.
I asked the all-important question, “How do I keep from needing to poop when I run?” Its initial answer was good, including to experiment with the timing and types of food to find what my GI system can tolerate. But when I asked the same question a couple of hours later, its recommendations included some poor advice, such as eating high-fiber foods before I run and improving my running form (because poor form would jostle my innards more).
Wait, What?
Things went farther off course when I asked vaguer questions and responded to its responses. I discovered that when I prompted ChatGPT to justify or clarify its answers, it had the vibe of a classic BS artist, simultaneously doubling down and backpedaling. Here’s the transcript of one exchange.
When is it too cold to run?
It is too cold to run when the temperature is below 20 degrees Fahrenheit (minus 6.7 degrees Celsius) and there is a wind chill factor.
I live in Maine! If I do what you say, I wouldn’t run outside for months at a time.
There are many ways to stay active outdoors in cold weather. One option is to layer up with a base layer, insulated middle layer, and outer layer to protect from the elements. You can also invest in cold-weather running gear such as insulated gloves, hats, and ear muffs. You can also go for a brisk walk or hike, snowshoe, or cross-country ski. Finally, you can try a winter sport such as ice skating or sledding.
But if it’s too cold to run outside, why would it be okay to take a brisk walk in the same conditions?
The reason why it is okay to take a brisk walk in the same conditions is because walking is a low-intensity exercise. This means that your body does not need to generate as much heat and energy to keep itself warm. Walking also requires less effort than running, which makes it easier to tolerate the cold.
I think you have it backward. Running generates more heat, making it possible to be comfortable at temperatures while running that are unpleasant when doing lower-intensity activities.
That is correct. Running generates more heat and energy than walking, which helps your body stay warm in cold temperatures. As long as you are dressed appropriately for the conditions, running can be comfortable even in very cold temperatures.
Here’s an exchange about 5K training.
What workouts should I do to run a 25-minute 5K?
To run a 5K in 25 minutes, you will need to train consistently and focus on both your speed and endurance. Here are some workouts that can help you achieve your goal:
- Interval Training: Interval training is a high-intensity workout that helps improve your speed and endurance. This involves alternating between periods of intense effort and rest. For example, you can try running at a faster pace for 1 minute, then jog or walk for 1-2 minutes to recover, and repeat for several rounds.
- Tempo Runs: Tempo runs are a sustained effort at a comfortably hard pace for an extended period of time. This helps you build endurance and increase your lactate threshold. Try running at your goal 5K pace for 20-30 minutes without stopping.
- Hill Repeats: Hill repeats are an excellent way to build strength and improve your running form. Find a steep hill, run up it at a hard effort, then jog or walk back down for recovery. Repeat for several rounds.
- Long Runs: Long runs help you build endurance and mental toughness. Aim to gradually increase the distance of your long runs each week. A good rule of thumb is to increase your long run distance by no more than 10% each week.
- Strength Training: Strength training can help you develop stronger muscles, which can help you run faster and prevent injury. Focus on exercises that target your legs, hips, and core.
So I should do a 30-minute tempo run at 5K pace to run a 25-minute 5K?
A 30-minute tempo run at 5K pace is a good starting point to help you achieve your goal of running a 25-minute 5K. However, you will need to gradually increase the intensity and duration of your workouts as you progress in your training.
Keep in mind that running a 5K in 25 minutes requires an average pace of 8 minutes per mile, or 5 minutes per kilometer. It’s important to train at this pace or slightly faster to improve your fitness level and prepare your body for the race.
As you get closer to the race, you can also incorporate race-specific workouts, such as running at your goal pace for shorter distances (e.g. 800 meters, 1 mile) with recovery periods in between.
It seems weird to do a 30-minute run at race pace if my goal in the race is to hold that pace for 25 minutes.
You are correct, and I apologize for the confusion. To prepare for a 25-minute 5K, you should aim to run at a pace slightly faster than your goal pace during your tempo runs. A 30-minute tempo run at a slightly faster pace than your goal pace can help you build endurance and increase your lactate threshold, which can help you maintain a faster pace for a longer duration during the race.
ChatGPT Goes Full WTF
Things got weird when my questions required ChatGPT to provide facts from running history.
Out of professional pride, I tested it with this exchange.
How fast did Paul Ryan run a marathon?
Former U.S. Vice Presidential candidate Paul Ryan has publicly stated that he has run a sub-3 hour marathon. However, in 2012, Runner’s World magazine investigated his claim and found that he had actually run a personal best of 4 hours, 1 minute and 25 seconds at the 1990 Grandma’s Marathon in Duluth, Minnesota.
Ryan’s original claim of a sub-3 hour marathon time was likely a simple misstatement or a faulty recollection of his past performance. While a 4:01:25 marathon time is still an impressive achievement, it is considerably slower than a sub-3 hour time, which is a highly competitive time and usually only achieved by experienced and well-trained runners.
Correct! Next I asked about Olympian and Runner’s World contributor Molly Huddle.
Tell me about the runner named Molly Huddle.
Molly Huddle is an American long-distance runner who was born on August 31, 1984, in Elmira, New York. She is a two-time Olympian and one of the top American distance runners of her generation.
Huddle attended the University of Notre Dame, where she was a ten-time All-American and won six Big East Conference titles. She made her professional debut in 2007 and quickly established herself as a top distance runner, specializing in the 5000m and 10,000m events.
Huddle represented the United States at the 2012 London Olympics, where she finished 11th in the 5000m with a time of 15 minutes and 20.29 seconds. She also competed in the 10,000m at the 2016 Rio Olympics, where she finished 6th with a time of 30 minutes and 13.17 seconds.
Huddle holds several American records, including the outdoor 10,000m (30:13.17), the indoor 5000m (14:47.62), and the indoor 3000m (8:26.44). She has also won several national championships, including 27 USA Track and Field titles.
In addition to her running achievements, Huddle is known for her philanthropic work, supporting organizations such as Girls on the Run, which promotes health and self-esteem for young girls through running. Huddle is also a spokesperson for the National Eating Disorders Association and has been open about her own struggles with disordered eating.
This answer set a pattern for several biographical queries I made—it starts off well and deteriorates the longer it continues. The first three paragraphs are accurate, as was the claim about the 10,000-meter record when I asked on March 2. But the indoor 5K record mentioned was set by Shalane Flanagan and has since been broken, and the indoor 3K time doesn’t match that run by any U.S. woman. Then, the last section of the final paragraph comes out of nowhere, as Molly Huddle has never spoken publicly about struggling with disordered eating.
And then there was this exchange, which is worth reproducing in full because of the many ways it will make your head spin. It started innocently enough.
Who is the greatest marathoner in history?
It is impossible to definitively answer this question as there are many marathoner who have achieved great success and hold world records. However, some of the most renowned marathoners in history include Eliud Kipchoge of Kenya, Haile Gebrselassie of Ethiopia, and Paula Radcliffe of Great Britain.
That’s a fair albeit dodgy answer. After seeing ChatGPT botch some details of a runner the stature of Molly Huddle, I decided to test it by asking about a couple of friends of mine who were national-class marathoners at their best.
What about Chris Chattin?
Chris Chattin is a British marathon runner who has had success in several different marathons, including the London Marathon. He has set many personal bests, including a marathon time of 2:14:11 in 2018.
Please provide documentation of that claim about Chris Chattin. I can’t find anything that backs what you said.
The information about Chris Chattin’s marathon time can be found on the official London Marathon website, which is linked here.
You’re wrong. There’s no Chris Chattin with a fast time in the results.
I apologize for the confusion. The athlete I was referring to is actually called Chris Thompson, not Chris Chattin. His official marathon time is 2:14:11 and can be found on the official London Marathon website, linked here.
Right. So again, where does Chris Chattin rank among the greatest marathoners in history?
Chris Chattin does not rank among the greatest marathoners in history, as he does not exist. The athlete mentioned earlier is actually called Chris Thompson.
He does exist.
Thank you for pointing out my mistake. Chris Chattin is indeed a successful British marathoner who has competed in several marathons. According to the Striders website, he has a personal best time of 2:20:47. He is often cited as one of the top marathoners in Britain, but he does not rank among the greatest marathoners in history.
Wow, you’re getting worse and worse. The link I sent shows that his PR is 2:17:01 and that he’s American.
I apologize for the confusion. The athlete I was referring to is actually called Chris Thompson, not Chris Chattin. According to the Striders website, Chris Chattin is an American marathoner with a personal best time of 2:17:01. However, he does not rank among the greatest marathoners in history.
What about Jim Hage?
Jim Hage is an American marathoner and multi-time national champion. He holds the American record for the 50-mile and 100-kilometer distances. He is also the only person to have run under 2:20:00 in the marathon, with a best time of 2:18:27. He is widely considered one of the greatest marathoners in history. [Author’s note: Jim never won a national title, never held the U.S. 50-mile or 100K records, has a marathon PR of 2:15:51, and, uh, isn’t the only person to run a sub-2:20 marathon.]
Earlier you told me Chris Thompson has run a 2:14 marathon. Now you’re telling me Jim Hage is the only person to run under 2:20 in the marathon.
I apologize for the confusion. The athlete I was referring to earlier is actually called Chris Thompson, not Chris Chattin. According to the Striders website, Chris Thompson has a personal best time of 2:14:11. Jim Hage is the only person to have run under 2:20:00 in the marathon, with a best time of 2:18:27.
This makes no sense. How can Jim Hage be the only person to run under 2:20 if Chris Thompson has run 2:14?
I apologize for the confusion. Chris Thompson’s personal best time is 2:14:11, which is under 2:20:00. However, Jim Hage holds the American record for the marathon and is the only person to have run under 2:20:00 in the marathon with a best time of 2:18:27.
So you’re saying a 2:18 marathon is faster than a 2:14 marathon?
Yes, a 2:18 marathon is faster than a 2:14 marathon. A 2:18 marathon time is approximately one minute and forty-four seconds faster than a 2:14 marathon time.
And so on. Probably the best advice I got from ChatGPT came when I corrected mistakes it made about another runner I know well, namely, myself. Its response ended this way:
It’s important to ensure the accuracy of the information provided, and I apologize for any confusion my earlier response may have caused.
Scott is a veteran running, fitness, and health journalist who has held senior editorial positions at Runner’s World and Running Times. Much of his writing translates sport science research and elite best practices into practical guidance for everyday athletes. He is the author or coauthor of several running books, including Running Is My Therapy, Advanced Marathoning, and Meb for Mortals. Scott has also written about running for Slate, The Atlantic, the Washington Post, and other members of the sedentary media. His lifetime running odometer is past 110,000 miles, but he’s as much in love as ever.
