Alyssa Konkel, from Illinois, was a the gym on May 24 when she decided to go for a run.
Viral footage shared online shows the 26-year-old – dressed in pink top and black leggings – suddenly trip on the treadmill track and desperately try to cling on to the handles.
As the machine keeps rolling, it catches her leggings and pulls them right down to her ankles, exposing her bottom before sending Alyssa flying off the back.
Alyssa said: ‘I felt so embarrassed. I had to leave immediately. I was just running at the gym and my pants got sucked off!’
Alyssa said: ‘The treadmill was on [level] ten so it was going pretty fast. ‘It was only when I watched the video back that I saw my shoelace was untied and I tripped and fell.
‘I jumped up, like up like a boss, immediately to pull my pants up because my butt was showing and that’s where I let go.
‘I hurt myself my face, lip, knees and shins are skinned.
‘Thankfully the gym was not too busy but the lady who ran back came back to me and asked if I was OK.’
Alyssa shared the video on her social media channels. The full video shows her running quickly on the treadmill for several seconds.
She appears to trip over and lose her balance for a split second.
Despite her best efforts to steady herself, arms out, she struggles to stand up straight and reaches out to grasp the handles on the machine.
The bottom of Alyssa’s legs make contact with the end of the machine, which she is unable to stop in the moment.
Her sportswear is suddenly pulled down by the rollers on the machine, leaving her helpless while her arms are still desperately clinging on to the handles.
Finally she lets go and appears to land headfirst on to the moving treadmill with her arms by her side.
Alyssa, defeated, is thrown off by the machine and collects herself on the ground.
She said: ‘This also happened when I was ten years old and skinned my chin, so now I’m really afraid of treadmills.’