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This is an ever-growing collection of exercises which have a definite grip element. Enjoy.
In the pinch grip, the fingers press an object against the thumb. Think of carrying a book, magazine or newspaper.
I first heard Jedd 'Napalm' Johnson talk about crimp grip in relation to tearing cards; and it's simply the variety of pinch grip that emphasises the tips of the fingers and thumb. Think of turning a screw-top lid on a wide jar.
Crushing grip is what most people think of as 'grip strength ', and it involves all fingers and thumb pressing an object against the palm. Think of a handshake.
Supporting grip is effectively crushing grip without the thumb. Think of holding the bar in a deadlift, or a Farmer's Walk.
These feats clearly demonstrate one or more varieties of grip strength. Superb.
This site also has several great article series on grip, including :
You might also like to look at the range of bending, tearing, kettlebell and club work we enjoy here. Great ways to train.