In BJJ, it’s important to be active with your grips. Your hands should always be busy, and if they aren’t, you’re not taking full advantage of your tools. When cross training, there are four main exercises I do to improve my grip, forearm, and wrist strength.
If you have a pull-up bar, throw your gi on it and pull yourself up. If you don’t have a pull-up bar, you can use a pole and lean back and pull yourself up. Explore gripping the lapels and sleeves in different ways.
You can do these with a barbell, dumbbell, water bottle–anything with some mass. Turn your palms so they’re facing down. Keep your elbows in. You don’t need as much weight as you would with a traditional bicep curl.
For this I have a small piece of PVC pipe with markings on it and a small weight (2-3 pounds) attached to the end. I grip the pipe with my thumb pointing up and bend my wrist up and down. Keep your elbows in and don’t rock your body. You can grip the pipe at different distances from the weight. The farther out you move your grips, the harder it becomes.
Grab two dumbbells, kettlebells, milk jugs (same weight on each side) and walk 50 yards. If you want more of a challenge, wrap the handles of dumbbells or kettlebells to make the grip fatter. If you have weight plates you can pinch grip and carry too.
Start out with small weights and low reps and build from there. I always include one or two grip-strengthening drills in my workout routine. You don’t need any special gym equipment; water jugs or bottles and your Gi is all. Attached are some videos to help.