Doctors have warned that excessive yacking on the mobile can result in "cubital tunnel syndrome", aka "mobile elbow", which could leave you too feeble open a jar of Marmite.
That's because if you have your phone glued to your ear for extended periods, keeping your elbow bent can overstretch and damage the arm's ulnar nerve. This vital piece of kit "extends underneath the funny bone and controls ring and little finger", the Telegraph explains, and if the blood supply is compromised, you'll be alerted by a tingling sensation.
US orthopaedic surgeon Dr Leon Benson warned of comms device-based ulnar nerve abuse, elaborating: "The more you bend it, for example when using a phone, the more it stretches. It diminishes the blood supply, and the blood is not flowing through the nerves.
"While the nerves are designed for stretching, it's not normal to be in a position to be stretched for an hour."
Severe cases of cubital tunnel syndrome may require surgery, but there's a simple solution to less drastic cases of enfeebled, tingling arms: If you're blathering away on the mobile and your ulnar nerve starts to protest, switch hands. ®