By Dr. José Antonio R. Piedrabuena
Physical exercise is probably the most comprehensive and cross-cutting intervention for improving human health. Its impact ranges from cancer prevention to reducing cognitive decline. Today we know that movement not only strengthens muscles: it transforms the entire body into a more efficient, resilient and youthful metabolic and immune system.
Exercise: a “medicine” with solid evidence
In adults, regular physical activity is associated with a 10 to 20 per cent lower risk of developing several types of cancer, including breast, colon, endometrial, bladder, and stomach cancer. In the cardiovascular sphere, the benefits are even more striking, with a 30 to 50 per cent reduction in the risk of cardiovascular disease and a 30 to 40 per cent decrease in mortality associated with these pathologies.
In addition, exercise improves cognitive functions such as memory and learning, and acts as a powerful natural antidepressant and anxiolytic. It is also crucial in the prevention and treatment of metabolic diseases such as obesity, type 2 diabetes and other related conditions.
Muscle: an endocrine organ that communicates with the entire body
Skeletal muscle is now recognised as a true endocrine organ. When it contracts, it releases a variety of molecules called myokines, which act on multiple tissues in the body. These include BDNF, nucleic acids, lipids and lactate, many of which are transported in exosomes, small vesicles that allow these “chemical messages” to reach distant cells. Among these substances, KLOTHO stands out, a protein that has been shown in animal models to rejuvenate and prolong life.
Interleukins: the messengers of the immune system activated with each contraction
When muscles work, they release interleukins that regulate essential processes in the immune system, from activation to cell proliferation. During exercise, these substances generate a generalised anti-inflammatory effect, increasing anti-inflammatory cytokines such as IL-1RA and IL-10, and decreasing levels of tumour necrosis factor (TNF).
Just 20 minutes of exercise is enough to induce a temporary but significant increase in lymphocytes, especially NK cells, CD8+ T cells and neutrophils, which are the most effective at eliminating tumour cells.
Lack of exercise: accelerated ageing
Muscle loss, weakness and impaired mobility, associated with a sedentary lifestyle and ageing, lead to higher levels of inflammatory and oxidative stress, an increased risk of vascular problems and premature ageing.
Exercise and the brain: more neurons, more connections, more protection
Regular exercise increases neurogenesis in the hippocampus, a region essential for memory, improves synaptic plasticity, intercellular communication, and multiple cognitive functions. This makes exercise a key tool in preventing neurodegenerative diseases.
Myokines: the molecular explanation for the overall benefits of exercise
After 30 minutes of physical activity, muscles produce myokines that optimise the metabolism of muscle, fat, liver, pancreatic, bone, heart, immune and brain cells. Some of the main myokines and their effects are:
- IL-6: improves glucose management, increases insulin sensitivity, reduces abdominal adiposity and has a marked anti-inflammatory effect after exercise.
- IL-8 and VEGF: promote angiogenesis, improve blood flow and oxygen transport to muscles and the brain.
- IL-15: promotes the creation of T lymphocytes and NK cells, enhances the oxidation of fatty acids to produce energy, and strengthens the immune response.
- BDNF (brain-derived neurotrophic factor): stimulates neural development, improves learning and memory, and protects against neurodegenerative processes.
- Irisin, BAIBA, apelina and meteorina: They promote the use of fat as energy and protect against metabolic diseases. Irisin transforms white fat into brown fat, which is more metabolically active, facilitating weight loss.
- IL-10, IL-1Rα and sTNFR: They reduce chronic inflammation and are useful in degenerative diseases such as osteoarthritis and Alzheimer's.
- SPARC and OSM: have anti-tumourigenic effects, suppressing colon tumours and inhibiting the growth of breast cancer cells.
In addition, exercise improves lung function, increases cardiac contraction strength, activates cilia (after about 30 minutes of swimming, improving the elimination of inhaled particles) and optimises kidney function.
Muscles need raw materials: the importance of nutrition
For exercise to be beneficial, it is essential to provide the muscles with the nutrients they need. Insufficient calorie or protein intake can lead to muscle catabolism, with consequences such as muscle loss, skin ageing (wrinkles) and hair loss.
A daily intake of 1.6 to 2.2 grams of protein per kilogram of body weight is recommended, distributed evenly across all meals. High-quality sources include eggs, lean meats, fish, dairy products, legumes, nuts, and seeds.
Other key nutrients include vitamin D, calcium, vitamin B12, iron, magnesium, leucine and HMB (which inhibits protein breakdown and improves cell integrity), and creatine, which is useful for strength and cognitive function.
An adequate intake of fruit and vegetables helps replenish glycogen and reduce muscle breakdown, while healthy fats, such as around 30 grams of olive oil per day, are vital for hormone production.
Conclusion: exercise as the cornerstone of holistic health
Physical exercise is not just a general recommendation: it is a molecular-based intervention capable of modifying the immune system, improving brain function, reducing inflammation, preventing cancer and cardiovascular disease, and delaying ageing.
When accompanied by proper nutrition, it becomes a powerful tool for ensuring health, longevity, and emotional well-being. Moving means living longer and living better.