Cómo mantener la testosterona en definición si eres natural por Roberto Castellano

How to maintain testosterone while cutting if you’re natural, by Roberto Castellano

February 25, 2026

SUPPLEMENTS FOR MAINTAINING TESTOSTERONE DURING CUTTING

Cutting is the phase in which almost all natural bodybuilders fall apart emotionally and physically, and even hormonally if they try to take it to the extreme—which is hardly surprising, since they tend to train more with the intention of preserving muscle mass, do cardio, and eat less: a perfect combination for messing things up.

They start well, motivated, losing fat, maintaining strength… and then suddenly, without really knowing why, constant fatigue, lower libido, a lack of energy during training, an increasingly irritable mood, and the feeling that the body is no longer responding in the same way begin to appear.

And there is something you need to accept in order to act accordingly: cutting and keeping testosterone high are competing goals. They are not mutually exclusive, but they do get in each other’s way. Testosterone responds very poorly to energy stress, prolonged deficits, excessive training volume, and insufficient rest. And a poorly planned cut brings all of these factors together at once.

That said, the fact that it is difficult does not mean it is impossible to keep it within a functional range. You will not have the testosterone levels of a bulking phase, but you can prevent them from plummeting prematurely. And that makes the difference between a controlled cut, with muscle preserved, and a cut where you lose fat… and also a large part of what you had built.

Let’s look at how to do this through three pillars: nutrition, supplementation, and training, always from the perspective of a natural athlete who cannot afford to make mistakes for too long.

UNDERSTANDING THE PROBLEM: WHY TESTOSTERONE DROPS DURING CUTTING

Before discussing solutions, we need to understand the context. During a cut, several factors come together that directly suppress testosterone:

Sustained calorie deficit.

– Reduction in body fat (especially when you drop below a certain threshold).

– Increase in cortisol.

– Greater training volume or frequency.

– Lower energy availability for the hormonal axis.

When the body senses that energy is limited, it prioritizes survival over reproduction. And testosterone, whether we like it or not, belongs to the second group. That is why the more aggressive and prolonged the cut, the harder it is to maintain optimal hormone levels.

Maintaining testosterone during cutting Moremuscle

NUTRITION: THE FIRST FILTER FOR PROTECTING TESTOSTERONE

Calorie deficit: be careful with it.

The most common mistake among natural bodybuilders is setting deficits that are too aggressive. A large deficit does accelerate fat loss, but it also spikes cortisol and shuts down the hormonal axis prematurely. In the short term it may seem effective; in the medium term it is a disaster, and in the long term it means leaving the sport.

To preserve testosterone, the deficit should be moderate and sustained, not extreme, with occasional slight surplus days to stimulate glycogen storage. This allows the body to adapt without entering “alarm mode” too soon. In practice, this means accepting that natural cutting is slower than Instagram promises.

Dietary fat: do not cut it as if it were the enemy

Testosterone is synthesized from cholesterol. This does not mean that eating fat will cause a dramatic surge in testosterone, but cutting fats too drastically does suppress it. During a cutting phase, many people reduce fat intake so much that the body runs out of hormonal substrate.

Maintaining a sufficient intake of healthy fats (extra-virgin olive oil, eggs, nuts, and fatty fish) is key to keeping the hormonal axis functioning. In fact, according to some studies, diets high in saturated fat may slightly increase testosterone.

Strategic carbohydrates to control cortisol

Carbohydrates are not only useful for performance; they also modulate cortisol. During a cutting phase, eliminating them or reducing them excessively increases physiological stress and promotes a decline in testosterone.

A smart strategy is to concentrate carbohydrates around training, where they serve several functions:

– They improve performance,

– They reduce the post-workout cortisol response,

– They facilitate recovery,

– And they make the diet more mentally sustainable.

It is not about eating lots of carbohydrates, but about eating them where they best protect the system, since they directly curb cortisol release, at least to some extent.

Protein: enough, but without absurd obsession

Increasing protein during a cutting phase makes sense for preserving muscle mass, but taking it to excessive levels can displace other macronutrients that are important for hormonal function. More protein is not always better if it compromises fats and carbohydrates.

Testosterone does not respond well to unbalanced diets. Balance matters more than rigidity.

SUPPLEMENTATION: WHAT REALLY HELPS

There is no supplement that will “keep testosterone high” during a cutting phase as if nothing were happening. What does exist are supplements that prevent it from dropping more than necessary.

Vitamin D3

Vitamin D is one of the basic pillars. Low levels are associated with low testosterone, poorer recovery, and a worse mood. During a cutting phase, when stress is greater, keeping vitamin D within the normal range is essential, not optional. It does not raise testosterone on its own, but it prevents it from declining further when the body is under pressure.

Zinc

Zinc is essential for testosterone production and the proper functioning of the hypothalamic–pituitary–testicular axis. During a cutting phase, with lower calorie intake and increased sweating, it is easy to develop a marginal deficiency without realizing it.

Its supplementation is not a “booster,” but it corrects a very common bottleneck during cutting phases.

Magnesium

Magnesium helps improve free testosterone by reducing its binding to SHBG and improves sleep quality. While cutting, sleeping poorly is common, and that has a direct impact on the hormonal axis.

Magnesium will not make you more masculine, but it will allow you to make better use of the testosterone you still have.

Omega-3 (EPA and DHA)

Chronic inflammation and metabolic stress suppress testosterone. Omega 3 helps reduce this inflammation, improves insulin sensitivity, and promotes a less hostile hormonal environment.

They do not act directly on testosterone, but they protect the context in which it is produced.

Ashwagandha

In natural bodybuilders while cutting, the problem is often not a lack of hormonal stimulus, but excess cortisol. Ashwagandha may help modulate this stress response, especially during long and demanding phases. It is not a miracle cure, but it can make a difference when the nervous system begins to become overloaded.

TRAINING: THE MOST COMMON MISTAKE THAT TANKS TESTOSTERONE

This is where most people go wrong.

Excessive volume

While cutting, many people train more “to burn more.” This is a classic mistake. Excessive volume raises cortisol, worsens recovery, and accelerates hormonal decline.

To maintain testosterone, training must be efficient, not endless. Fewer junk sets and more quality stimulus.

Maintaining intensity

Testosterone responds better to strength and intensity stimuli than to endless pump sessions. Maintaining relatively heavy loads (within what cutting allows) sends the body a clear signal: “this muscle is still necessary.”

Losing intensity too soon is an invitation to catabolism.

Cardio: the minimum necessary

Cardio is useful for creating a deficit, but overdoing it is one of the fastest ways to tank testosterone in a natural athlete. Especially long-duration, high-frequency cardio.

Using it as an occasional tool, not as a daily punishment, is key to avoiding hormonal-axis dysregulation. In these cases, staying below 65% of maximum heart rate is a good option.

Rest between sessions

Reducing rest days too much or always training with accumulated fatigue increases systemic stress. While cutting, recovery is just as important as training.

Maintaining testosterone while cutting Roberto Castellano Moremuscle

REALISTIC EXPECTATIONS: THE KEY TO PRESERVING YOUR DEFINITION

Here is the article’s most important message: you cannot get extremely lean and maintain high testosterone indefinitely as a natural athlete. That does not exist. What you can do is:

– Delay the decline

– Avoid sudden crashes

– Maintaining functional levels for longer

– And planning strategic breaks or diet breaks when necessary.

CONCLUSION: CUTTING SHOULD BE A STRATEGY, NOT A COINCIDENCE

Maintaining testosterone while cutting naturally does not depend on a magic supplement or a perfect diet. It depends on not pushing harder than your physiology can tolerate, respecting the timing, and understanding that the goal is not to suffer more, but to lose fat while preserving muscle and hormonal function.

Balanced nutrition, a moderate deficit, sufficient fats, strategic carbohydrates, thoughtfully selected basic supplementation, and smart training. That is what separates a professional cut from a self-destructive one.

References

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