High-Intensity Interval Training Isn't Worth The Extra Effort, New study Finds

A new study finds that exercising the high-intensity interval training (HIIT) isn’t worth the extra effort since exercising at a moderate intensity produces almost the same results.

The researchers at the University of Alberta sought to analyze the differences in the intensity regulation during an interval training-style exercise regimen. The study included eight participants who regularly engaged in functional fitness training and were made to repeat the same circuit-based workout regimen once at a high intensity and another time at a moderate level.

Moderate intensity is defined as a six out of 10 on the rate of ‘perceived exertion scale’ (RPE), where one is considered very light and six as a higher end of strong and a full 10 is considered ‘all-out’. The findings of this study suggested that while the overall repetitions in the all-out sessions were higher and most of the exercises were done in the first couple of four-minute sessions. And by the time the all-out group got to the next two sessions, they were found to be at the same amount of reps similar to those who exercised at a lower intensity.

“The data showed exercising at an intensity level of six enabled you to still reap the positive benefits of the activity while not exhausting you so much that you are not able to sustain this level over the course of an individual session or over time with multiple sessions," said the study’s co-author Joao Falk Neto to MedicalXpress.

The researchers opine that physical injury is linked to functional fitness training risks since individuals ignore the pain signals in their attempt of going all-out for a long period of time. They also reported that intense-type exercises increase the risk of illnesses due to low immunity levels. Extreme fatigue is also said to be associated with such intense training which can negatively impact people’s emotional well-being.

The study also highlighted the lactate response which impacts acidity in muscle cells found in HIIT compared to lower-intensity levels. It was noted that such lactate concentration can lead to dizziness, nausea and reduced muscle power and can lead to conditions that affect motivation to exercise.

The authors emphasize that if the same physical benefits can be achieved from a lesser-intensity exercise which also improves your overall adherence to physical activity, there is no use in taking that extra effort to perform HIIT.

The study’s lead author Kennedy noted that it is all about working smarter and not harder. When the similar positive outcomes can be achieved by working out at a moderate intensity, he recommends switching to moderate intensity workout which also decreases the risk of high-intensity workouts and makes you feel healthier, happier and stronger.