Which of the following is a disadvantage of interval training?

• A. Expensive to Implement
• B. It Offers No Cardiovascular Benefit
• C. Cannot Be Used for Team Sports
• D. Can Be Difficult to Identify How Hard Someone Is Working

Answer: (D)

Interval training relies on hitting specific high-intensity efforts and then recovering, so how hard the athlete is actually working on each interval is crucial for the benefits. The main difficulty is judging and controlling that effort in real time. Heart rate responses can lag behind actual exertion and are influenced by factors like heat, hydration, fatigue, and recent activity, so simply watching a monitor may not give an exact picture of how hard the work interval really is. Perceived effort (how hard the exercise feels) helps, but it’s subjective and can vary a lot between individuals and from day to day, making it hard to prescribe the correct intensity for everyone or for repeated sessions. Because getting the intensity right is essential for improving speed, endurance, and power without overdoing it, this measurement challenge stands out as a key disadvantage. Using tools like heart rate monitors or RPE can mitigate it, but they don’t eliminate the variability, so prescribing interval efforts remains tricky.