How to do the shoulder stretch
Bring one arm straight across your chest and use the other forearm to gently press it closer. Keep the shoulder of the stretched arm down and away from your ear.
How long to hold it
The most common recommendation for a static shoulder stretch is 20 seconds per side, repeated 3 times, with a short break to switch sides. That is exactly how this timer is pre-configured: press start and it counts every hold, tells you when to switch sides with a distinct sound, and gives you 20 seconds of rest after the final rep. Your eyes never leave the floor.
Common mistakes
Shrugging the shoulder up during the hold, pressing on the elbow joint itself, and rotating the torso instead of isolating the shoulder.
Why it's worth doing
Desk work stiffens the posterior shoulder capsule. Regular cross-body holds restore reach-across range and ease tension that creeps up into the neck.
About this timer
ExtendTimer is a free stretching timer with sound cues for every phase: a steady tick while you hold, a count-in when you switch sides, and an alert on your final rep. It works offline, installs to your home screen like an app, and needs no account. Routines of up to two stretches are free forever; Pro ($4.99/month or $29.99/year) unlocks unlimited routines and the full sound studio.