You bend your arms at the elbow and forcefully press your palms into each other. Your hands do not move and the muscles of your upper arms do not shorten, but tension greatly increases in them. This muscle contraction is described as being

isometric contraction

Explanation:

Isometric contraction is a class of contraction where the muscle maintains a constant length as tension is produced, thereby the length of the muscles does not change during this process. Isometric contractions are performed without joint motion. They are appropriate for the rehabilitation of musculotendinous traumas due the muscle maintains a static position and contraction intensity can be controlled. This type of contraction is common for the muscles in the hands and arms.

emerald ash borer

the emerald ash borer is a green buprestid or jewel beetle native to north-eastern asia that feeds on ash species. females lay eggs in bark crevices on ash trees, and larvae feed underneath the bark of ash trees to emerge as adults in one to two years. hope this !