Post from Josi · April 4, 2026

Rear Biceps Flexing Marathon 💪🔥 (10:50 min)

I filmed this on March 16, 2026 — and pushed my right arm to its limit.

For over 10 minutes, I keep my right bicep fully flexed, showing you the muscle from the back angle while the tension builds and the burn kicks in.

You’ll see:

continuous contraction without restdetailed shoulder & bicep interactionslow adjustments while staying fully flexed

This is a full endurance test for my arm.

💬 Extra content (on request only):

2 additional clips filmed right after — including close interaction with the flexed biceps.