Mini cuts are short periods, usually only a few weeks, in which you aim for fat loss while maintaining muscle mass. They are often used to prevent the fat percentage from rising too high during a bulk. It is evident that you can cut calories more deeply in a mini cut than in a regular cut. But how deep exactly? Is even a crash diet responsible?
RESEARCH
To answer that question, we look at a study by Oxfeldt et al. (2023) among female, experienced strength athletes. This compared a daily energy intake of 50 kcal/kg fat-free mass (2403 kcal) with 25 kcal/kg fat-free mass (1349 kcal) during an intensive training block of ten days. Protein intake was the same in both groups: 2.2 g/kg lean mass.
Thanks to a calculation by coach Menno Henselmans, we see that their actual energy deficit amounts to a deficit of 16% (443 kcal/day) for the higher energy intake and 52% (1443 kcal/day) for the lower energy intake.
RESULTS
Extensive laboratory testing combined with the aggressive program allowed researchers to observe significant effects despite the short study period.
It will not surprise you that the group with a low energy intake did worse on almost all points, except fat loss. They lost 0.4 kg of lean mass, probably mainly muscle mass. The group with a relatively high energy intake recorded an increase of 0.4 kg of fat-free mass.
Metabolism in the crash dieters slowed down due to a reduction in thyroid hormone levels and resting metabolism. The free testosterone level also decreased. On the plus side, they lost 1.3kg of fat, compared to 0.5kg in the higher energy intake group.
BODY RECOMPOSITION
The group with a higher energy intake therefore experienced a significant positive body change: simultaneous muscle growth and fat loss, or body recomposition. This shows once again that even trained strength athletes without much excess weight can achieve body recomposition, the holy grail of natural bodybuilding.
CONCLUSION
The crash diet group lost more fat, but this was almost certainly not worth it, given the difference in lean body mass and the negative protein balance and metabolic slowdown.
Conclusion based on this research: trained strength athletes with healthy body fat levels keep their energy deficit much closer to 16% than to 52%, even with mini cuts.
We generally recommend an energy deficit of 20-25% when cutting. With mini cuts you can possibly go a little higher, up to 30%. But definitely don’t make it a crash diet.