JARGON BUSTER

We explain common medical terms . . .

THIS WEEK: isotonic

THIS refers to the contractions that occur in muscles, making them shorten or lengthen in order for us to move.

The word isotonic comes from the early 19th century, a musical term based on the Greek ‘isotonos’; ‘isos’ meaning equal, and ‘tonos’ meaning tone. Our muscles shorten during exercises such as bicep curls and situps; these are called concentric contractions and are the most common isotonic movements. Eccentric contractions, on the other hand, are where your muscles lengthen.

This happens during exercises such as squats, which cause the quadricep muscles in the thigh to lengthen as you descend.