San Diego CA— High-intensity interval training (HIIT), intense interval exercise with short rest periods, has taken the fitness world by storm with its purported ability to produce significant results with much shorter workouts. Could a minutes-long HIIT workout help time-strapped, sedentary Americans improve their health? The American Council on Exercise (ACE) commissioned an independent study from researchers at University of Wisconsin–La Crosse to compare the physiologic responses of two HIIT workouts (Tabata and a less intense interval training workout) with steady-state cardio exercise in previously inactive young adults.
“In the study, the HIIT workouts didn’t produce significantly greater improvements in markers of aerobic and anaerobic exercise performance compared to steady-state cardio for sedentary young adults,” said ACE Chief Science Officer Cedric X. Bryant, Ph.D. “Arguably, one of the more interesting findings of this study was the significantly lower level of enjoyments reported by individuals in the Tabata training group compared to the other two training groups.” This lower level of enjoyment associated with Tabata workouts could potentially result in poor long-term adherence, according to American Council on Exercise.
In a study led by Carl Foster, Ph.D., researchers recruited 65 relatively sedentary young adults between 18 and 28 years old who hadn’t exercised more than twice per week at a low-to-moderate intensity in the prior three months. Prior to randomly assigning each participant to one of three eight-week, three-sessions-per-week stationary cycling programs, researchers measured the study participants’ exercise capacity. The first group performed 20 minutes of steady-state, moderate-to-vigorous intensity exercise. The second performed four minutes of Tabata training in sets of 20 seconds of highly intense exercise followed by 10 seconds of unloaded, recovery pedaling. The third group performed 20 minutes of interval training consisting of sets of 30 seconds of intense exercise followed by 60 seconds of recovery pedaling. Each week, participants rated their enjoyment level of the exercise program.
Indicators of fitness and cardiorespiratory health, such as VO2max and body-weight normalized power output, improved for all the groups over the course of the study at very similar rates despite the vast differences in the exercise programs. The Tabata group indicated the lowest amount of enjoyment, and their enjoyment declined the most over time. All groups’ enjoyment levels decreased steadily over the eight-week period.
“While very important, the effectiveness of a fitness program matters relatively little if participants find it unpleasant and something they would unlikely adhere to for the long haul,” Bryant added. “The results of this study appear to suggest that the high-intensity nature of the Tabata workouts served as a turnoff for previously inactive participants. These findings help to reinforce the principle that it is critically important that health and fitness professionals design exercises programs that are individualized and appropriate for the needs, interests and abilities of their clients or activity participants.”
To view the study, visit: https://www.acefitness.org/certifiednews/images/article/pdfs/ACE_HIITStudy.pdf

About ACE

The nonprofit organization American Council on Exercise (ACE) educates, certifies and represents more than 58,000 currently certified fitness professionals, health coaches and other allied health professionals. ACE advocates for a new intersection of fitness and healthcare, bringing the highly qualified professionals ACE represents into the healthcare continuum so they can contribute to the national solution to physical inactivity and obesity. ACE is the largest certifier in its space and all four of its primary certification programs are accredited by the National Commission for Certifying Agencies (NCCA), the gold standard in the United States for accreditation of certifications that assess professional competence. ACE also plays an important public-service role, conducting and providing science-based research and resources on safe and effective physical activity and sustainable behavior change. For more information, call 800-825-3636 or visit ACEfitness.org. AMERICAN COUNCIL ON EXERCISE, ACE and ACE logos are Registered Trademarks of the American Council on Exercise.