If you find that you are having difficulty taking the breathing in for the amount of time that Dr Joe is instructing, it is likely that you are either trying too hard or taking too deep of a breath.
Allow yourself to relax and breath in slowly.
If you can't hold your breath for as long as instructed, you might be breathing in too fast. That's okay. Just let go, relax, and start again.
For detailed information and instruction by Dr Joe, we recommend the download Pulling the Mind Out of the Body, which is a compilation of lectures by Dr Joe on the breathing technique.
This download is available on the Unlimited website at the following link:
Pulling the Mind Out of the Body
Inspire, Volume 1 - Ten Tracks to Master the Breath by Dr Joe Dispenza