Which of the following is an example of flexibility?

Flexibility refers to the range of motion available at a joint or group of joints and is essential for overall physical fitness. Yoga poses are practiced specifically to enhance flexibility by stretching various muscle groups and improving the elasticity of the muscles and connective tissues. This focus on stretching and lengthening muscles is a key characteristic of flexibility training.

In contrast, bicep curls primarily target muscle strength and hypertrophy rather than increasing flexibility. Plank exercises are isometric and focus on core stability and strength, while high-intensity interval training (HIIT) prioritizes cardiovascular fitness and muscular endurance through short bursts of intense activity followed by rest. These other options do not emphasize the stretching and range of motion that is essential for flexibility, making yoga poses the best example in this context.