Considering they're a womens race boot, you will struggle to get enough purchase with the velcro to be safe on track. I had to put duct tape around the top to hold them shut. I don't even have big calves, they just haven't taken into account the fact that women have longer calves to men. My friend also had to do the same to hers. Even casually, I still struggled to get the cuff of my Motogirl cargos in there and also do up the boot appropriately enough to be good for the road. I make do and do use them and they are comfortable and supportive, but I feel like this is major design flaw. I haven't tested this but have heard the Dianese womens boots do account for this, so maybe have a look there.