Competitors in the Strongman Champions League showed their mettle in Zhengzhou, China, during the doubles airplane-pulling competition, hauling a 34.6-ton Boeing 737-300 over distance of 20 meters in one of the events. The winning pair covered the distance in 35.9 seconds in what is a true test of mental and physical strength.

“It’s a tough event for the whole system, muscles and heart, and brain, because your body is cramping and swelling up because of lactic acid. But then you look back and what you just did and it’s like ‘I just pulled that airplane,'” says one entrant.

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