uploading videos from imovie to vimeo takes hours

I record classes I teach on my iphone, edit them in iMovie and then upload them to Vimeo. The classes are at 720 dpi and about 60 minutes in length. It can take upwards of 2-3 hours to upload one video from iMovie to my Vimeo plus account. I contacted Vimeo and they said it is a iMovie problem.

"It looks like you’re using a third-party software to upload directly to Vimeo. This feature makes use of Vimeo's API, but the uploading process was built and maintained by Apple. Therefore, it’s not in our power to troubleshoot or fix any issues that may arise."

How can I troubleshoot this issue because this can't be right. I upload multiple classes a day and it takes me hours just to get a couple up there. Please advise.