Defending your life isnt something that you can place a schedule on. You have to be ready to do it all the time. In those instances when its awkward to bring a bag and your mobile phone and keys are the only things that you can bring you will have to use either of those things for self-defense if necessary.
Or that is exactly what my own self-defense instructor tells me. I definitely wouldnt wish to strike my very own enemy using my android phone but a set of keys is a different matter because it is a whole lot cheaper.
As a librarian I often keep late hours and every other Friday I go out for a couple of drinks along with my pals. On those Fridays I just bring my wallet mobile phone as well as house keys along with me since I do not expect to drive back home.
The idea of utilizing keys for personal protection is not new however the trick is in learning the proper method to hold them. I was thinking that the most comfortable way with the head of the key flush between my fingers was fine but it ended up being the weakest grip.
In training we were trained to hold a key with the head flat on the mounds of the palm at the base of the fingers or to grip it as if you are turning an automobile key. Seemingly it was much more stable.
After that session together with my coach I purchased this Heart Attack keychain that I can grip easily. Its black and shaped more like the spade on a deck of cards. The Heart Attack is similar to though a lot better than keys.
One time we nearly got into a fight outside the club but after seeing that we got something sharp coming out of our knuckles the other guys decided to just leave.
You cant be too choosy regarding the tools you use for defending your life. You need to be flexible enough to get by with anything handy. In my case I made certain I have just that.