First, you have to understand that in order to train the grip, you not only do gripping style exercises, but you must also train the muscles on the opposite side of the joint. Most of the the exercises you probably do involve holding on to weights – this works the flexor (gripping) muscles. Often athletes neglect extensor training completely, so integrate 2 exercises to your grip strength program:
1) Reverse ez-bar curls 2) Rubber band finger extensions
For #2, you can use a thick elastic band (the kind that usually comes around broccoli) or buy a tool called the PowerWeb. Just stick your fingers in the band and try to straighten and spread your fingers apart.
Now to train the gripping muscles themselves, you want to hit the 3 components: strength, endurance, and power.
Strength of the grip muscles is generally not an issue if you're performing exercises like heavy Deadlifts or Chinups. If you regularly deadlift, you can probably lift at least 300 pounds – if not, get lifting!
Endurance is another component that you need, so to build endurance, you can do something I call Grip Finishers – simply do your normal exercise, let's say a set of 10 chinups, then hold on to the bar with a strong grip for as long as you can. This is best done on your last set, because you'll ruin your subsequent sets by fatiguing your grip. Deadlifts, Barbell curls, and Dumbbell lunges are also good candidates.
Now gripping power is often not trained and can really help you out in MMA or BJJ competitions. Power is force x velocity, so you need to be able to apply your full grip strength quickly to develop a powerful grip.
My favourite method of training grip power with my mixed-martial artists is to do an exercise I call Plyo chinups. Do a chinup, then when your chin is over the bar, let go of the bar and then grab on again as you straighten your arms, then pull yourself up as quickly as you can. The farther you let yourself drop, the better. But start off with a smaller drop and work your way up – these are really demanding.
You can also use this method with 1-arm dumbbell rows.
Other ideas to develop your grip are to do exercises holding onto towels instead of holding the bar. This is great for chinups, dumbell lunges, etc. If you train or compete in BJJ with the Gi then you'll definitely benefit from this exercise.
You can also use a fat bar handle instead of a regular dumbbell or barbell. Just wrap an old t-shirt around the handle to increase its diameter and it will give you a totally new challenge.
Whatever methods you do, make sure you only do 2 weeks of grip training, then take 2 weeks off. Because you're always working your gripping muscles, constant specialized grip training can lead to overtraining or worse – injury, so be sure to back off after 2 weeks.
Give those concepts a shot and you'll have a crushing grip in no time.
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