Researchers challenge high-intensity interval training critics

The promotion of high-intensity interval training (HIIT) for public health is a lightning rod for debate, especially from its staunchest critics within the scientific community.

Now researchers at UBC Okanagan continue to advance the HIIT discussion while also calling out a lack of civility and respectful dialogue among scientists who may disagree with evidence-based findings.

“In our view, critics have unfairly questioned the validity of studies that show positive psychological responses to HIIT, including enjoyment of, and adherence to HIIT as an exercise intervention,” says Dr. Mary Jung, a Professor and exercise researcher with UBC Okanagan’s School of Health and Exercise Sciences. “They also argue that HIIT is only suitable for athletes or as part of a supervised fitness program.”

By studying psychological responses and adherence levels in different real-world settings, the UBCO researchers challenge these assumptions. In research published recently in the Applied Physiology, Nutrition, and Metabolism journal, Dr. Jung and co-author Dr. Kathleen Martin Ginis, say the debate threatens to derail the research and future advancements in health sciences.

“Evidence suggests HIIT is just as enjoyable as moderate-intensity continuous training,” says Dr. Jung. “In supervised situations, adherence is similarly high for both methodologies and in unsupervised situations is similarly lower for both.”

According to researchers, HIIT offers positive health outcomes for a wide range of populations, including people living with chronic conditions, of varying ages, and those with limited exercise experience. They say that despite the prevailing evidence, online discourse and opinion pieces attempt to silence healthy debate and discredit HIIT scientists.

“What began as an open debate on the value of HIIT as a public health strategy has now devolved into attacks on researchers,” says Dr. Martin Ginis, Director for UBCO’s Centre for Chronic Disease Prevention and Management.

Dr. Martin Ginis questions if these attacks are intended to intimidate scientists to abandon HIIT research altogether. She notes that the academic discourse has already slowed advancements in exercise science, as researchers—especially graduate students—feel intimidated. Some have decided not to conduct, publish or present research on HIIT for fear of coming under personal attack.

“If the scientific community continues to accept the false narrative that HIIT is a debatable, two-sided issue, the losses to time, effort and ultimately scientific advancement are significant,” she adds.

For many scientists working in the field of exercise psychology, the ultimate goal is to improve physical activity levels which would then lead to an improvement in people’s lives and well-being.

“Since 2015, the debate has moved beyond the practical question of whether HIIT is viable for population-level physical activity promotion, to the philosophical question of whether HIIT research should be abandoned altogether,” adds Dr. Martin Ginis. “By positioning the HIIT discourse as a binary, right or wrong ‘debate,’ discussants have created an adversarial paradigm for conversations and a breeding ground for incivility.”

Drs. Jung and Martin Ginis will continue to champion the approach of respectful dialogue and encourage thoughtful, scientific discussions.

“We recommend that attention be directed toward improving behavior change and maintenance for all types of exercise,” adds Dr. Martin Ginis. “Resources are better spent addressing fundamental questions about exercise initiation and adherence than perpetuating a vitriolic and uncivil debate over the value of high-intensity versus moderate-intensity training.”