The physics of tennis strings going dead

I've never cared much about the intricacies of my tennis setup, and I doubt — or hope — that even the pros don't spend this much time choosing perfect strings for their perfectly balanced racquets. Give me a million-dollar sponsorship and I'll switch from Head to Babolat without a blink.

Thankfully, not everyone is so disinterested in the science of tennis. Tennis Warehouse University hosts deep scientific experiments on tennis equipment: polymer viscoelasticity, hysteresis curves, energy return, and the real reason strings "go dead" (spoiler: it's inter-string friction, not tension loss).

The finding: tension loss matters less for power than the increasing friction between strings that inhibits lateral movement of the mains, this what players actually feel as "deadness."