I know a lot of people don't really care about forearm or hand exercise for grip strength, but I personally believe it is very important to not neglect the hands and forearm. For those that are in full contact sports such as boxing and martial arts this will be a good asset for you. Using strenuous workouts on the wrist builds strong bones and strengthens the tendons to where injuries can be rare. It is also proven that it can prevent arthritis in the hands as well as injuries
But why would anybody want to train the hands? for those that are in the strength industry working the hands can give you an edge on your lifts. You will be able to increase your lifts in a short amount of time, especially in the pulling exercise like deadlifts. Besides the lifts having great hand strength you'll be able to show off to your friends the strength you obtain by ripping phonebooks, cards and much more.
Also having a strong grip would allow you to open up jars that your mom or best friend keeps opening up for you.
Here are some different kinds of exercise that you can use to help increase your grip strength.
-The Pinch Grip is when the fingers and thumbs are stressed forcefully against an object. This workout focuses on the tiny muscles in the fingers, which increases the strength in your hands for crushing.
-The Common Squeeze Grip: You can purchase a gripper from sports store and learn to crush them in your hands. This is the basic exercise of strengthening your hands and wrist. You can take a small rag, ball it up and squeeze it.
There are so many ways of developing hand strength. Using thick handled dumbbells or barbells are a proof of enhancing hand strength. Not only does it bring increase amount of strength in your hands, but it also builds stability in the body. You may be able to curl a 30lb dumbbell with some ease with high reps, but curling the same weight with thick handles will bring difficulty in the exercise and possiblities of performing low reps. Not only will you feel it in your biceps, but your whole arm will be in shock, not to mention your abs, shoulders and legs. Fat Gripz or Grip4orce will be a great asset to use for dumbbells, barbells and such if you don't have thick steel handles for the weights. If you cannot afford it use a towel. Wrap a small towel around the handle of the dumbbell to where it will be comfortable and thick enough. Proceed by curling the dumbbell and then bring it down to your side. Your hands will be forced to squeeze as you do not want to drop the dumbbell.

Here is a study that shows the following:

“Among healthy 45- to 68-year-old men, hand grip strength was highly predictive of functional limitations and disability 25 years later. Good muscle strength in midlife may protect people from old age disability by providing a greater safety margin above the threshold of disability.”

Author's Bio: 

James Pappoe is a Certified ISSA Personal Fitness Trainer, a mix martial artist, mix martial arts coach, strength and conditioning coach and a performing strongman that performs feats of strength. He has performed in front of a live crowd of 10,000 on the island of Haiti. Not to mention those that watched him live on television thorughout the island of Dominican Republic and Haiti. James has performed at events, festivals, schools, churches and juvenile halls.