Muscle outlines from Body Muscles by Ivan Vulović, Apache 2.0 — regrouped and recoloured for Muscle Train.
Attach a handle to a cable machine at shoulder height. Stand sideways to the machine, feet shoulder-width apart. Grasp the handle with your working hand, palm down. Start with your upper arm parallel to the floor, elbow bent 90 degrees. Keep your non-working hand stable for balance. Fully extend your arm, straightening it. Pause briefly, contracting your triceps. Slowly return to the starting position. Switch arms after completing the desired repetitions.
Maintain a stable stance. Keep your upper arm stationary, moving only your forearm. Control the movement throughout. Avoid forceful elbow lockout. Engage your core. Start with a lighter weight. Exhale during extension, inhale during the return.
MuscleTrain is actively being built. If something looks broken, or you have a suggestion, let us know — it really helps shape the app.