1. having the same concentration of dissolved particles as another solution, especially as body fluids
Usage: biology; chemistry
2. involving muscle contraction with movement but constant tension
Usage: exercise physiology

Examples

• The isotonic saline solution matched the salt concentration of blood.
• Doctors use isotonic fluids to prevent cell damage during IV therapy.
• Isotonic exercises like swimming help build muscle strength and endurance.
• The sports drink was formulated to be isotonic with body fluids.
• Isotonic contractions allow joints to move through their full range of motion.
• The cell remained stable in the isotonic environment.
• Weight lifting with full range of motion is an example of isotonic exercise.