Adherence
High-intensity interval training (HIIT) and sprint interval training (SIT) enhance mitochondrial respiration and function, whereas long slow-distance (LSD) training with higher volume is required to increase mitochondrial mass.
To improve your aerobic capacity, you don't always need to spend hours exercising. Incorporate high-intensity interval training (HIIT) or sprint interval training (SIT) to boost mitochondrial function efficiently. If your goal is to increase the total amount of mitochondria (mass), focus on longer, lower-intensity sessions with higher volume.
Overall, these studies suggest that high-intensity training is important for increasing mitochondrial activity, whereas a greater training volume is needed to increase mitochondrial mass (MacInnis et al. 2016).
Why this rating
The paper cites multiple human studies (Granata, Jacobs, MacInnis) showing consistent trends, though it notes discrepancies due to subject status and methodology.
Source
Adaptations to Endurance and Strength Training
David C. Hughes et al. · Cold Spring Harbor Perspectives in Medicine · 2017
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