• Mayo Clinic Minute: Human performance ⎯ will there be a 2-hour marathon?

Many people are driven to succeed. Some want to be the best, fastest or most qualified at whatever they do. In the sports world, elite athletes are working to run marathons in less than two hours. Dr. Michael Joyner, a Mayo Clinic anesthesiologist, studies human performance and discusses whether this is possible.

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Dr. Joyner has studied human performance since medical school. He says that in the 1970s and 1980s, some ideas about the limits of human performance began to emerge. Three main factors were identified.

"Something called 'maximal oxygen uptake,' which is the equivalent of how big the engine the athlete has," Dr, Joyner says.

The second thing was something called the 'lactate threshold,' which is how much of the athlete's engine capacity can be used and for how long.

"Then something called 'running efficiency' or 'running economy,'" Dr. Joyner says.

But what if one person had all three attributes?

"It turns out you could make an equation about how these interact, and I estimated somebody would break two hours for the marathon," Dr. Joyner says.

So far, the record is 2:01:39. Dr. Joyner says if, during a race, all conditions are right somebody will do it in the early 2020s or 2030s.

"But it could happen suddenly because that's how these things go," Dr. Joyner says.