Originally Posted by Brendan McNamar
If the thinner ban allows you to do 1-5 reps then you are building strength.
If a thicker band allows you to do 8-15 you are building stamina.
So if you are doing 3 x 5 pull-ups to get strong enough to do pull-ups without a band use thinner band.
If your doing a met-con like Fran where you will do 45 pull-ups fast use the thicker band.
Exactly. Totally depends on the workout OP is doing. If you're doing a WOD with lots of pull-ups, be sure to use a band that will allow you to do a higher volume (until you figure out whats right for you, err on the side of a bigger band). When you're doing a strength workout, find a band were you can do 1-5 reps max.