What physiological changes occur as a result of regular exercise?

Regular exercise leads to numerous beneficial physiological changes in the body, particularly through long-term adaptations within various body systems. These adaptations include improvements in muscle strength and endurance, increased cardiovascular fitness, enhanced flexibility, and better respiratory function.

For instance, when a person engages in consistent aerobic exercise, their heart becomes more efficient at pumping blood, which can lower resting heart rate and increase stroke volume. Similarly, strength training induces muscle hypertrophy, leading to greater muscle strength and power. These adaptations contribute to overall improved physical performance and can positively influence metabolic processes, even at rest.

On the other hand, decreased muscle strength, increased risk of injury, and reduced cardiovascular efficiency can occur due to factors such as inactivity, poor training practices, or overtraining. However, with regular exercise, individuals typically experience the opposite of these scenarios. The long-term adaptations that take place enhance the body's function and overall health, making option B the most accurate representation of the effects of regular exercise.