18 unless accompanied by an adult
It is listed as adults and teens. I don't know if there is an official age, I haven't seen a sign. My kids are very into their sports, they started using the treadmills alone at 10 & 12 without issue. For my soccer and cross country runner, it was a must, especially as they are early risers and there is pretty much nothing to do early in the morning.
18 or 19 perhaps
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