Can you jog in this without it digging in?

Yes! My 16 year old daughter wears these on both ankles for all volleyball games and practices. Her team has a very extensive conditioning program, including lots of running. She says the Ultra Zoom braces are great & don't dig in nor impede her mobility whatsoever. Highly recommended!!

Does this brace come as a single or pair?

This is Rick from Ultra Ankle. Our ankle braces are sold in single units, not pairs. Should you have any additional questions you can reach out to me directly via email at support@ultraankle.com

How do you break it in with out body heat

This is Rick from Ultra Ankle. Thanks for your question. By just wearing the Ultra Zoom you create the body heat that allows the Performathane shell to form-fit to your ankle. If need be you can use a regular hair dryer to heat up the shell, then apply the brace to the ankle over a full sock and insert in the shoe. This method can help accelerate the break-in period. However, some individuals find that there is no break-in period at all. Everyone is different. For addition information, or if you have further questions please go to the Ultra Ankle website, “Ask A Question” section. There you can email me directly.

Will these fit inside police/military style boots?

This is Rick from Ultra Ankle (not Amazon). The Ultra Ankle model that would fit the best in a police/military style boot is the Ultra Zoom model. The Ultra Zoom has a soft shell that uses body heat to custom fit to the ankle. You would need to undo your laces a bit more to get the brace in the boot but it would work. If you would like to correspond more with additional questions go to the Ultra Ankle website and click the Ask A Question link. This way we can correspond via email.Thank youRick Peters