High intensity interval training, also referred to as HIIT, is believed to be the holy grail of exercise modalities for fat loss. HIIT is indeed a viable method to promote fat loss, but how does it stack up against steady state cardio (prolonged maintenance of the same running pace)? Let’s see what form of cardio exercise is more efficient at burning fat: HIIT vs. steady state!
HIIT vs. Steady State
Luckily, in 2017, the nerds conducted two meta-analyses on that exact question (1,2).
Side note: meta-analyses are thought to be the highest levels of evidence. So listen up.
Here’s what the research team did in one of the analyses: they examined 6,074 studies and excluded any study with a duration of less than 4 weeks. To further validate their findings, they investigated the heterogeneity of the available evidence. This plucked out the studies where the populations/samples were different and eventually chiseled the 6000+ number to 31. These 31 studies are what they used to draw a conclusion and give us the most accurate answer.
The findings may surprise you (or maybe they won’t). I surely was surprised. Researchers concluded that there was no difference in body fat outcomes when workload and/or energy expenditure were matched, between HIIT vs. steady state cardio.
Which One Should I Choose?
My biases have a higher affinity for the findings of the other meta-analysis, which suggests HIIT is superior for fat loss (2). Although this evidence exists suggesting HIIT is better than steady state, this evidence cannot quite stack up as high as the first meta-analysis, due to less studies being taken into account (31 vs 18) and other limitations within this meta-analysis.
“The overall quality of the included studies was low . . . Details about the randomization process and allocation concealment were lacking in almost all studies, so the risk of bias was unclear . . . Also in 4 studies [~22%], the number of participants was low, ranging from 12-18, with the risk of overestimation or underestimation of the effect on outcome parameters.”
So what does this mean for you? This means that you are allowed to have a preference and still experience benefits. HIIT may not be for you and that’s okay. But if you are someone who is always on a crunch for time, HIIT will most likely be better suited for your lifestyle than steady state, due to its efficiency. In contrast, if you are someone with time to spare and high intensities are not your thing, steady state cardio is perfectly fine.
Cardio Exercise Fun Facts
The American College of Sports Medicine (ACSM) currently recommends the following (3):
- At least 30 minutes of moderate intensity cardio 5 days a week or an accumulation of 150 minutes per week
OR
- At least 20 minutes of vigorous intensity cardio 3 days a week or an accumulation of 75 minutes per week
The National Strength and Conditioning Association (NSCA) recommends work:rest ratios for HIIT to be within the range of 1:3 to 1:5 (4).
Ex: 10 seconds of intense work followed by 30-50 seconds of recovery
The NSCA also recommends prolonged aerobic activity be performed at intensities of 60-70% maximum heart rate (HRmax).
How to estimate HRmax: 220 – your age = your estimated HRmax in beats per minute (bpm)
How to determine your optimal heart rate during exercise in bpm: (220 – your age) x intensity
Ex: I am 25 years old. My heart rate range for prolonged aerobic exercise should be within 117-137 bpm ((220 – 25) x 60% and (220 – 25) x 70%).
The Importance of Eating Right
That said, if your caloric intake still exceeds your caloric expenditures, you will not experience any weight loss with either activity. Exercise is a powerful tool that can accelerate changes in body weight, but what you do in the kitchen will always reign superior over what you do in the gym, when the topic is weight management. For more info on how to implement either form of aerobic activity or nutritional strategies to enhance fat loss, get in touch with Elite’s trainers and Nutrition staff!
Set up a Free Fitness ConsultationReferences:
1) Keating, S., Johnson, N., Mielke, G., and Coombes, J. A systematic review and meta-analysis of interval training versus moderate-intensity continuous training on body adiposity.Obes Rev. 18(8): 943-964, 2017.
2), , , , , , , and High intensity training in obesity: a Meta-analysis. Obesity Science & Practice. 3: 258–271, 2017.
3) Garber, C., Blissmer, B., Deschenes, M., Franklin, B., Lamonte, M., Lee, I-M., Nieman, D., and Swain., D. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: Guidance for prescribing exercise. Medicine & Science in Sports & Exercise. 43(7): 1334-1359, 2011.
4) Haff, G. and Triplett, T. Essentials of strength training and conditioning. 4thed., Human Kinetics, 2016.