Which are the primary categories of exercise described in movement therapies?

• A. Isotonic, Isometric, Isokinetic
• B. Aerobic, Anaerobic, Resistance
• C. Flexibility, Balance, Endurance
• D. Cardio, Strength, Mobility

Answer: (A)

Movement therapies typically classify therapeutic exercise by how the muscle contracts under load: isotonic, isometric, and isokinetic. Isotonic work involves a change in muscle length against a constant external resistance, which allows the joint to move through a range of motion and trains dynamic strength. Isometric work generates force without any change in muscle length, holding a position to build static stability and joint compression without movement. Isokinetic work maintains a constant movement speed with resistance that adjusts to the effort, emphasizing controlled, smooth motion through a full range.

This trio is the most practical framework for therapists because it describes the fundamental ways muscles can produce force during rehab and training, guiding how to load tissue, protect healing structures, and tailor progression. The other options describe broader energy systems (aerobic/anaerobic), functional targets (flexibility, balance, endurance), or contemporary labels (cardio, strength, mobility) that reflect outcomes or strategies rather than the core contraction modalities used to categorize movement therapies.