What intensity level should one aim for in the Target Heart Rate (THR) zone for cardiorespiratory endurance?

The Target Heart Rate (THR) zone for developing cardiorespiratory endurance is generally identified as being between 60 to 85% of a person's maximum heart rate. This intensity level is supported by exercise science, which indicates that maintaining a heart rate within this range allows for enhanced cardiovascular fitness, optimal fat burning, and improved aerobic capacity.

The lower end of this range (60%) provides enough intensity to stimulate the cardiovascular system while being an achievable effort for individuals beginning an exercise program. The upper end (85%) challenges experienced individuals, pushing their limits to improve endurance and performance. This combination ensures a well-rounded approach to cardiorespiratory conditioning, making it effective for various fitness levels.

In contrast, aiming for a lower intensity, such as 40 to 60% of THR may not provide sufficient stimulus to significantly enhance cardiorespiratory endurance, particularly for individuals who have already established a basic fitness level. Higher ranges (like 70 to 90% of THR) can be suitable for advanced athletes but may not be sustainable for longer durations and could increase the risk of injury or fatigue for those who are not conditioned for such intensity. Therefore, 60 to 85% of THR strikes the right balance for promoting