4Arm Strong

[nate]

www.climbing.com/gear/sponsor-content/
www.youtube.com/watch?v=0oq22gQuabg

WTF?

"For a climber a stronger grip speaks for itself, however rock climbers should avoid strengthening their grip with resistance or weight training. Resistance, or weight training can cause the muscles in the forearm compartment to become larger, thus increasing the risk of arm pump."

Seems pretty suspect. Obviously it's sponsored content but it shows up in the gear section of climbing.com along with their supposed "actual" gear reviews. I mean those reviews are basically just sponsored content as well because they rarely have anything constructive to say but at least they aren't usually full of total bs.

[MarkAnderson]

Ya, pretty funny stuff. It's great that they came right out and made that comment about strength training--now it's firmly established that they have zero credibility.  

If you want to try it, simply press your other thumb into your forearm while you do the arm motion described in the video. I didn't notice anything different from the sensation of deep tissue massage in the same location.  Deep tissue massage is certainly helpful IME, so to that extent it probably is beneficial. But I don't see the advantage in using a whacky device for that, other than the thought of wasting your money might motivate you to do it more frequently.