What's the Best Way to Maintain Muscle During a Cut?

The most effective way to maintain muscle during a cutting phase is to minimize caloric restriction while maintaining training intensity, as demonstrated by elite bodybuilder research showing that even with a 44% calorie reduction, muscle thickness decreased only 5-28% across different muscle groups. The key is understanding that some muscle loss is inevitable, but strategic approaches can minimize it significantly.

Key Finding

A detailed case study of a 38-year-old Mr. Olympia competitor revealed that during his contest preparation, despite reducing calories from 5,620 to 3,140 per day (a 44% decrease), he lost only 6.4kg of total body weight while maintaining most of his muscle mass. The study used ultrasound imaging to track muscle thickness changes across nine different muscle groups, providing unprecedented insight into how elite bodybuilders preserve hypertrophy during extreme dieting phases.

Study Details

Researchers from the University of Bologna followed a professional bodybuilder (128.7kg, 176cm) through both his bulking and cutting phases leading up to competition. They used B-mode ultrasound to measure muscle thickness and echo intensity in nine muscles: elbow flexors, triceps brachii, pectoralis major, upper trapezius, vastus medialis, vastus lateralis, biceps femoris, and medial and lateral gastrocnemius.

The team also analyzed detailed training and nutrition logs, tracking changes in body composition through skinfold measurements. This comprehensive approach provided a complete picture of how an elite athlete's physique responds to the extreme demands of contest preparation.

Results

The findings challenge common assumptions about muscle loss during cutting phases:

Caloric Changes:

Body Composition:

Muscle Thickness Changes:

Echo Intensity Changes:

The data suggests that when tracking your training and nutrition precisely like this athlete did, significant muscle preservation is possible even under extreme conditions.

Limitations

This study has several important limitations to consider. First, it's a single case study of an elite athlete with exceptional genetics, training experience, and likely pharmaceutical support—results may not apply to recreational lifters. Second, the study period was relatively short, focusing only on the final preparation phase rather than a complete annual cycle.

Third, ultrasound measurements, while precise, can be influenced by hydration status and glycogen levels, potentially confounding the interpretation of muscle thickness changes. The researchers acknowledged this limitation, noting that echo intensity changes likely reflected glycogen depletion rather than true muscle quality changes.

What This Means for Your Training

For most lifters pursuing hypertrophy, this research offers several practical insights. The most important finding is that muscle loss during a cutting phase is not as dramatic as many fear, especially when training intensity is maintained. The athlete preserved most muscle mass despite an extreme 44% caloric reduction, suggesting that moderate deficits (20-25%) should allow even better preservation.

The study reinforces the importance of maintaining your resistance training program during a cut. The bodybuilder kept his training largely unchanged, prioritizing consistency over dramatic modifications. This aligns with current hypertrophy research showing that training volume and intensity are crucial for muscle preservation.

Different muscle groups responded differently to the cutting phase, with the upper trapezius showing the greatest loss. This suggests that some muscles may be more vulnerable during caloric restriction, potentially requiring targeted attention in your program.

The echo intensity changes highlight an often-overlooked aspect of cutting: much of what appears to be muscle loss may actually be glycogen and water depletion. When using tools like Kenso to track your progress, understanding this distinction can help you make better decisions about when to adjust your approach.

For practical application, focus on maintaining training intensity, tracking your progress consistently, and accepting that some temporary changes in muscle fullness are normal and reversible. The key is distinguishing between true muscle loss and the temporary effects of reduced carbohydrate intake and glycogen depletion.

How much muscle mass can you expect to lose during a cutting phase?

Based on this elite bodybuilder case study, muscle thickness decreased by 5-28% across different muscle groups during an extreme 44% caloric reduction. Most recreational lifters using moderate deficits should expect significantly less muscle loss.

Which muscle groups are most vulnerable during a cut?

The upper trapezius showed the greatest muscle thickness reduction (-28.4%) in this study, followed by the gastrocnemius medialis (-12.8%). However, individual responses may vary based on training focus and genetics.

Should you change your training program when cutting?

No, this research supports maintaining your existing resistance training program during a cut. The bodybuilder kept his training largely unchanged, which likely contributed to his impressive muscle preservation.

How can you tell the difference between muscle loss and glycogen depletion?

Echo intensity measurements in this study increased significantly, indicating changes in muscle composition likely related to reduced glycogen stores rather than true muscle loss. Visual changes in muscle fullness often reflect hydration and glycogen status more than actual hypertrophy changes.

What's the most important factor for maintaining muscle during a cut?

Maintaining training intensity and volume appears most critical, as demonstrated by this athlete's approach. Consistent resistance training, combined with adequate protein intake and moderate caloric deficits, provides the best foundation for muscle preservation.

Citation: Rosaci, G, Biban, S, and Bartolomei, S. Beyond the Limits of Human Muscle Hypertrophy: A Case Study of a Mr. Olympia Competitor Bodybuilder. Journal of Strength and Conditioning Research, 2026. DOI: 10.1519/JSC.0000000000005519

Ready to track your own cutting phase with the precision of an elite athlete? Download Kenso and monitor your training consistency, volume, and progression throughout your entire preparation. Train with intention, not just intensity.