Increasing the thickness of the grip you use while training can help you see new gains in strength and size.
Yet most trainees never alter their grip at all. Always sticking to the standard thickness of the dumbbells and barbells they have available.
If you have the forearm development of a chopstick thick grip training is definitely something you need to start doing. Not only that it will transfer over to more strength on nearly all other upper body exercises.
The main reason most will use thick grip training is for bicep exercises like curls. No doubt they work great for training arms but if you only use them for that you're missing out. Over head Presses, rows, pullups, bench press's deadlifts, skull crushers, lateral raises, tricep extension. Its just another way to change the training stimulus and get a new adaptation.
You're only as strong as your weakest link; and grip strength so therefore the strength of the hands and forearms are often the weak link for many. Overuse of straps on pulling exercises such as rows, deadlifts, and pulldowns only add to the problem by taking the grip out of the equation. This allows you to lift more weight, but the downside is your grip misses out on valuable training stimulus.
Another bonus is using fat grips on dumbbell and barbell pressing exercises can make your joints feel better and and clear up niggling pains in your wrists, elbows and shoulders normally associated with pressing. The weight is spread over a larger area in your hands and is a more natural pushing position. For me the bar always feels more stable and comfortable using fat grips than without.
The easiest way to start doing some thick grip training is to get some "Fat Gripz". These solid rubber cylinder like attachments clip on to nearly all barbells and dumbbells as well as other handle attachments. They feel nice and solid in your hands but still are fairly easy to put on and take off.
One thing though don't get all excited and use fat grips on every exercises in your training. You can over do it and you should still use normal dumbbells and barbells some of the time. They are just another tool to have in your toolbox.
You can get Fat Gripz from www.fatgripz.com.au