It is good that you are a cave-person - because we are talking about running like a primitive human - the way we were designed to run before marketing took over the activity called "running".
we have to talk - lots of ideas here.
several questions and all that...
Anyway, here is some general advice: Follow the 10% rule. If you are running 3.5 miles per week now, in trainers, then add no more than 10% barefoot. So that means about a third of a mile barefoot to your total 3.5. The next week, increase total (shod+barefoot) distance 10% = 3.75 miles. The next week, add 10% more barefoot, so run about 2/3 miles barefoot. etc. Alternate between weeks - one week add 10% more barefoot miles to the previous week's total, the next week upping your total mileage 10% more.
I have no trouble switching from barefoot to flats and back. But, there are a lot of people in the barefoot community that say that is not good because it retains your bad habits from running shod. They say simply go into it 100% from the start, but forget about doing the total mileage you are used to.
It is a good idea to start on grass. Find a nice soccer field to run circles around. Run there, or warm up in shoes first. Run the field loops shod first and look for anything that you can step on that might hurt and throw it far away or remember to avoid it. Then take them off and run for 5 minutes around the soccer field. Do that a couple times per week. Begin to increase your 5 minutes barefoot by a minute or two per session. Before you know it you will be doing quite a lot of minutes of running barefoot. (BTW, that is how I measure BF running, by minutes, not miles. As a barefoot beginner, you should not try to train as fast as you are used to while barefoot, so don't court injury - don't worry about how far you are going - add up the minutes instead.
Orthotics - ween yourself off of them. Wear them a couple of times per week, don't wear them a couple times per week. Increase the latter and decrease the former. To support the transition, go barefoot at all times, except when you are absolutely forced to wear shoes! Push the limits. Carry flip flops and put them on when the store manager asks you to - but make sure you tell him it isn't illegal anywhere and that you could bring him to court for discrimination if you were not such a nice person.
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