What is the physical mechanism by which we grab hold of things? Can one improve upon their grip? Is the mechanism fundamentally different when you’re grabbing something to prevent yourself from falling, as opposed to preventing something from falling out of your hand? Why can I hold onto a remote control for hours at a time but can only hold onto a horizontal bar for a few seconds?
Basically, give me the Straight Dope on the concept of grip.
Friction. And depending on the orientation you’re holding something you just have whatever normal forces are acting on the object.
Yes. Squeeze harder.
No.
I don’t know what this means. What’s a horizontal bar? Probably it’s heavier than a remote control.
I mean, like, a parallel bar suspended off the floor. I assume I can only hang onto it for a few seconds because I’m supporting my own weight and not that of the bar?
I mean, can one train oneself over time to grip things longer and better? How would I go from being able to only hold onto a rope for a few seconds to being able to do it longer and learn how to climb it, for instance?
Assuming you weigh more than a remote. Also, hanging from a bar creates tension through your arms while holding a remote is probably just resting on your hand and grip wouldn’t come into it at all.
Sure. You can train anything. There are grip exercises. Rope climbing is more about legs and technique than hand grip though.
Grip strength is also predictive of mortality risk as we age. So get a grip.
There’s a whole sub-industry of grip strength training apparati and instructions out there. The reason being, having a strong grip is a boon for many if not most physical activities, and often a lacking grip strength is the very limit to one’s performance; ie. other muscles could do it, but the grip fails early. And that is definitely an improvable condition.
No particular need to go for the specialised stuff; simply gripping, lifting and holding heavy things will improve one’s grip by leaps and bounds. I know it did improve mine.
One simple trick is to increase the diameter of the weight bar; this increases the task / reward on the gripping muscles while creating no additional strain elsewhere.
So you have access to a horizontal bar.
Seriously start just trying to increase how long you can hang from it, repeat several times. At some future point you may get able to even tuck your knees up while hanging, or jump up into top of pull up position and slowly lower yourself down. Grip strength increase and more.
It’s the orientation of your fingers against the force of the object, as well as how much pressure you can apply in that orientation. Friction may be a factor (like when gripping a flat steel plate), or not really at all like when you’re holding a pencil in your fist; generally you can hold something much tighter if you can wrap your digits mostly or completely around it.
Yes, though the amount is limited a bit by the orientation you’re gripping from. If you can’t generate enough force in the first place (eg try gripping a 4" diameter pipe and hanging from it) it’s hard to get better; you can’t really improve on what you can’t do in the first place so you need to modify the movement.
No
Very little pressure required to prevent gravity acting on the remote to force your fingers open.
Rope climbing, as mentioned, involves a lot more than just grip, and you’ll have a hard time doing the standard technique if you can’t also (mostly) do chin-ups. There are techniques using your feet to create a sort of ladder to push up against and reduce reliance on upper body strength, but you’ll still need to be able to hold your bodyweight while re-positioning your feet every few seconds.
There are also different types of grip strength, depending on whether you’re dynamically squeezing vs static holding something, as well as what kind of grip you use. Opening a wide jar lid is different than hanging from a horizontal bar, but both heavily rely on grip strength.
The simplest grip strength exercises involve holding something heavy (especially with a fat grip) for as long as you can, then gradually increase the time. Another broad category are weighted or cable curls where you do reps and increase weight like other exercises. Tons of references online.
I have pretty good general strength, but my grip strength is drastically reduced because of osteoarthritis in my thumb and forefinger joints. Am I doomed to an early death?
A Grip is responsible for setting up, rigging, and striking lighting equipment on set. They are also responsible for keeping equipment organized, and sometimes equipment maintenance. A Key Grip in film is the boss of the Grips department. And there are also Dolly Grips who assist the Camera department by physically moving the dolly.
Nevermind. Just pay it no mind at all. 
The future is unclear at this time.
But do you have good life insurance?
Yeah, I thought so There’s no one foolish enough to sell me life insurance, but I don’t earn any money to speak of nowadays anyway, so there’s a silver lining.
I accidentally greatly improved my grip strength by working in a car wash when I was a teen. My job was to clean the interior of the cars, so I had a squeeze bottle and a rag. One hand/forearm gets tired, switch hands, repeat as needed for eight hours a day. After that job, my skinny ass self could crush steel and my forearms were mini-Popeye things. Then a career, much of which involved using hand tools, kept things toned. Nowadays, arthritis in the thumbs means I can’t even open a stubborn mayo jar, even though the strength is mostly still there.
Obviously I wasn’t being serious … but it does illustrate the conundrum of these markers and associations.
One presumes that grip strength is a marker that travels with overall fitness and healthy habits. The average person maintains good grip strength as a result of the things they are doing, things that have benefit to healthspan. But is it possible that poor grip itself actually contributes to poorer outcomes? Sure. I can make up lots of stories for that right off the top of my head. Grip is required for many activities of daily living and poor ability to perform those activities can have huge impacts. Grip is used to prevent falls and falls lead to huge numbers of problems and even deaths. So on.
So seriously who knows?
Yeah, I assumed it’s just one of the things to watch out for. I’m much more concerned about how hard it’s getting for me to stand from a squat nowadays, so I should go reread the weight-lifting thread!
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