Fit and vital from 30: Dr. René Blanka in an expert interview about training, nutrition and testosterone levels

Testosterone and growth hormones play a key role in maintaining vitality well into old age. Rather than relying on testosterone supplements, natural measures—particularly a healthy lifestyle that includes strength training, an optimal balance of macro- and micronutrients, and relaxation—can promote performance during the second half of life.

serotalin®: Dr. Blanka, you have extensively studied the body’s self-healing powers and the effects of training on hormones and metabolism. Can you explain how testosterone levels change in men over 30, and what effects this has on their health?

For many men, testosterone levels gradually decrease with age; however, there are also men who do not experience a significant decline in this hormone even in old age. Since it is the most important male sex hormone with numerous anabolic functions in the body, its decline has various effects on physique, health, and performance.

A testosterone deficiency can manifest in sexual problems, fatigue, or depression, as well as increased body fat and reduced muscle mass. It may also lead to disorders in fat metabolism, the immune system, blood formation, or lower bone density. Over the past decades, the proportion of men with testosterone deficiency in Western industrialized nations has significantly increased, as evidenced by both German and American studies.

serotalin®: You oppose the use of medication and instead advocate targeted training and proper nutrition. What specific training methods and nutritional strategies do you recommend to boost testosterone levels in men over 30?

When someone is prescribed testosterone supplements by a doctor, their body reduces its own production of the hormone in the testicles. This exacerbates the root cause of the deficiency, while the medication only addresses the symptoms. In my opinion, this is harmful in the long term.

The European Urology Societies also recommend first using natural approaches, such as specific diets and exercise, and only resorting to testosterone therapy if these methods fail. However, there are situations where medication is necessary—for example, if the hormone deficiency is caused by a tumor.

serotalin®: Your research focuses on optimizing metabolism and hormones. What role does testosterone play in this context, and how can improving its levels affect overall health and vitality in men?

Testosterone is an anabolic (building) hormone, which is why testosterone preparations are often used as doping agents. It promotes protein synthesis and muscle growth while aiding fat loss. Mentally, it enhances sexual drive, energy, and ambition.

Testosterone is a steroid hormone that is mostly bound to transport proteins in the blood. However, only the unbound, free testosterone is biologically active. It binds to receptors on target cells, triggering synthesis processes in the cell nucleus. For these biological processes to function effectively, there must be sufficient receptors for the hormone. Thus, the total level of testosterone in the blood alone does not determine a man’s health and performance.
The ratio of testosterone to the stress hormone cortisol, which acts as an antagonist, is also crucial.

The ratio of testosterone to the stress hormone cortisol – which is an important antagonist – should also be taken into account.

serotalin®: You’ve written extensively about the effects of training on hormones and metabolism. What insights from your work are especially relevant for men over 40?

Testosterone prepares us for short, intense exertion. It stimulates muscle growth, sharpens alertness, and mobilizes energy in stressful or dangerous situations. Understanding these functions provides clues about the types of training that increase its production.

Intense exercise, such as strength training and interval training, is key to stimulating testosterone production. On the other hand, excessive endurance training reduces testosterone levels. For example, in competitive athletes such as marathon runners or triathletes, it can even lead to testicular shrinkage.

Men need intense physical activity to boost testosterone levels, but this effort can only be sustained for short periods. In the mental sphere, the ability to relax is equally essential for maintaining optimal testosterone levels. Effective stress management also helps keep cortisol levels low.

For this reason, in my opinion, men should not worry too much about their testosterone levels and should not fall into the habit of optimizing them.

serotalin®: As a longtime strength athlete, you’ve experimented with various training methods. Are there specific exercises or programs you recommend for men over 30 to optimize testosterone levels?

Strength training is my top recommendation because testosterone is actively involved whenever muscles grow. A full-body workout is best for increasing this hormone. Multi-joint exercises that target multiple muscle groups simultaneously are more effective than single-joint isolation exercises. Training with free weights is preferable to machines, as it requires more coordination.

High-intensity interval training (HIIT) also benefits hormone production, though it should only be performed by healthy individuals, as it places significant stress on the heart. Sprints can also boost testosterone levels.

When planning workouts, it’s important to include adequate recovery time between sessions, as overtraining can lower testosterone levels. Similarly, endurance training should be kept within limits to avoid suppressing hormone production. For men over 40, intensive training is particularly effective for increasing testosterone levels, in contrast to the often-recommended "moderate" exercise.

serotalin®: You have served over 5,000 clients. Can you share some success stories where men over 30 have experienced a change in their testosterone levels and overall health through your program?

Testosterone levels fluctuate depending on many factors. It depends on the time of day, but stress or a cold can also cause it to drop. In addition, different laboratories use different methods to determine testosterone levels, which can also lead to different values. It is basically only relevant if there are also clinical symptoms (signs of illness). Therefore, we should not concentrate on a single value such as total testosterone, but rather see the hormonal situation in a larger context.

You can build muscle at any age with targeted training. During this process of muscle growth, it is assumed that more testosterone is produced. And this increased amount of testosterone is not only available to the muscles, but has an effect throughout the body. I have trained many men over the age of 50 who demonstrably built muscle, reduced body fat and became more vital, optimistic and healthier thanks to the increased hormone production.

serotalin®: How important is the role of nutrition in regulating testosterone levels, and are there certain foods or nutrients that you particularly recommend for men over 40?

I would first like to point out a seemingly paradoxical connection on this topic. Nutrition is the intake of nutrients; however, avoiding certain foods is usually the key to increasing testosterone production. Fat cells (especially those in the abdominal cavity) can absorb testosterone, inactivate it and convert it into a female hormone. If more energy is consumed through food than is used, body fat will increase and testosterone levels can fall as a result.

Increased blood sugar also reduces the production of this sex hormone, which is why it is better to avoid foods with a high sugar content. In contrast, the reduced food intake during fasting often increases testosterone production. There is also evidence that an excessive intake of protein causes levels to drop.

For good testosterone production, the diet must contain enough fat, because this steroid hormone is produced through the conversion of cholesterol. Too little fat in the diet can lower testosterone levels. It is also important to consume enough omega-3 fatty acids; the best sources are fish oil, algae oil, fatty sea fish (herring, mackerel, salmon, etc.) and linseed oil. Studies have shown that testosterone levels benefit from supplements containing high-quality fish oil.

Vitamin D is also important for hormone production – in the autumn and winter months when there is little sun, testosterone levels often drop because less of this vitamin is produced.

Foods such as oatmeal, broccoli, onions, garlic or grapefruit can increase testosterone in the short term through various mechanisms. Preparations containing Korean ginseng are also said to have hormone-boosting properties. In comparison to the previously mentioned information on increasing hormones through food, both effects are, in my opinion, overestimated.

serotalin®: You also have experience as a hospital manager and in managing healthcare facilities. What challenges do you see in the current healthcare system in terms of preventing and treating hormonal changes in men, and how could your approach help to address these?

Medicine can be divided into preventive and curative medicine. The majority of the resources available in the health system are used in curative medicine, i.e. in the diagnosis and treatment of diseases. Unfortunately, the preventive sector leads a shadowy existence. In my opinion, targeted training in combination with a healthy diet (both elements are part of preventive medicine) can make a decisive contribution to preventing diseases and reducing biological age.

Strong muscles are the key to remaining mobile and independent as we age. As we get older, more and more of the original muscle mass is lost - a process with serious consequences for health and performance. The loss of muscle leads to an increasing loss of strength, which ultimately makes us immobile, which creates a corresponding need for care.

Loss of muscle mass also reduces our energy consumption, which is why body fat increases as a result. A lack of muscle mass leads to an increased risk of type 2 diabetes mellitus. Men who suffer from type 2 diabetes often also show a lack of testosterone. In recent decades, research has shown that muscles produce hormone-like signaling substances (myokines) that can have a positive effect on internal organs and promote our health. With appropriate training, the production of these health messengers can be increased.

Muscles grow even in very old people if they are trained specifically; increases in strength can also be achieved at any age. Testosterone plays a key role in these processes - this can be seen in the fact that women do not achieve muscle growth comparable to men and also in the fact that muscles only start to grow in young men during puberty when testosterone production increases .

Good testosterone levels are a prerequisite for muscle growth in men, but also for sufficient bone density. I assume that the spread and promotion of targeted strength training through our health system - supported by a healthy diet - could significantly reduce the costs incurred by the need for care for older people. Furthermore, in my opinion, this would largely prevent widespread diseases such as obesity, type 2 diabetes and osteoporosis.

About the author:

Dr. med. René Blanka is a training expert, specialist in the field of cell biology and author of numerous books. Blanka has also participated in various studies. His "Dr. med. Blanka Method" aims to support healthy aging with the help of special training, nutritional strategies and individual stress management.

Book tip: Hormones that inspire men by Dr. med. René Blanka