Mixed
Interval training (IT) and moderate intensity continuous training (MICT) produce equivalent changes in whole-body fat mass and fat-free mass over time.
If your goal is to change your body composition (lose fat or gain muscle), it does not matter whether you choose high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT). Both approaches yield similar results. Focus on choosing the type of exercise you enjoy and can stick with consistently, as adherence is likely more important than the specific intensity profile for long-term body composition changes.
Our findings provide compelling evidence that the pattern of intensity of effort and volume during endurance exercise (i.e., IT vs MICT) has minimal influence on longitudinal changes in fat mass and FFM, which are likely to minimal anyway.
Why this rating
The study is a systematic review and meta-analysis of 54 randomized controlled trials, rated as 'high certainty' by the GRADE framework.
Source
Slow and Steady, or Hard and Fast? A Systematic Review and Meta-Analysis of Studies Comparing Body Composition Changes between Interval Training and Moderate Intensity Continuous Training
James Steele et al. · Sports · 2021
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