During ageing, anabolic status is essential to prevent the decrease in quantity and quality of skeletal muscle mass (SMM). Exercise modulates endocrine markers of muscle status. We studied the differences of endocrine markers for muscle status in 62 non-sarcopenic Mexican swimmer adults aged 30–70 y/o, allocated into two groups: the systematic training (ST) group including master athletes with a physical activity level (PAL) >1.6, and the non-systematic training group (NST) composed by subjects with a PAL <1.5. Body composition, diet, biochemical and endocrine markers were analyzed. The ST group showed lower myostatin (MSTN) and irisin (IRI) levels, two strong regulators of SMM. The insulin growth factor-1 (IGF-1) was higher in the ST. This is consistent with most of the evidence in young athletes and resistance training programs, where IGF-1 and IRI seem to play a crucial role in maintaining anabolic status in master athletes.

Background: Obesity is a worldwide health problem. Genetic studies have shown the association between rs1805086 localized in myostatin (MSTN) gene with body fat; however, there is little evidence of its relation with metabolic disturbances. Aim: To determine whether rs1805086 is associated with obesity and metabolic disturbances in a Mexican adult population. Subjects and methods: We genotyped rs1805086 in 1,024 men and women aged 18-58 years. Anthropometric and body fat data were used to estimate obesity. Biochemical parameters were measured and DNA was used to determine the rs1805086 genotype. Results: rs1805086 heterozygous AG frequency was 5.4%, and the homozygous for the risk allele GG was absent. Heterozygous had higher levels of body mass index (BMI) and waist/height ratio (WHtR). Heterozygous subjects showed a greater total and central obesity compared to the homozygous for ancestral allele AA (OR BMI >30 kg/m²₌ 2.35, 95% CI 1.29-4.29; OR WHtR >0.5 = 2.03, 95% CI 1.19-3.45; OR elevated fat mass (EFM) %= 1.72, 95% CI 1.01-2.92; OR fat mass index (FMI)>p85 = 1.96, 95% CI 1.05-3.68). rs1805086 was not associated with metabolic alterations. Conclusion: Heterozygosity for rs1805086 showed a predisposition to having elevated overall and central obesity parameters. This association with adiposity seems to be independent of metabolic risk.

Background: In Mexico, research on somatotypes in athletes has primarily focused on team sports, taekwondo, climbing, and triathlon. However, the available evidence remains limited. Therefore, the purpose of this study was to determine the somatotype of Mexican athletes by sex, and to compare somatotype and body composition across sport macro-categories in 43 disciplines. Methods: Anthropometric measurements were conducted according to the International Society for the Advancement of Kinanthropometry (ISAK) protocol. Athletes who participated in regional, national, or international competitions between 2008 and 2024 were included. Results: A total of 889 Mexican athletes (477 males and 412 females) across 43 disciplines were evaluated. Among male athletes, the predominant somatotype was endomorphic mesomorph (52.4%), followed by balanced mesomorph (17.6%) and ectomorphic mesomorph (13.6%). Among female athletes, the most reported somatotypes were endomorphic mesomorph (24.5%), mesomorphic endomorph (24.0%), and mesomorph-endomorph (21.4%). Athletes in endurance sports showed significant differences for both sexes compared to those in power and skill-based sports for both sexes (p < 0.05). Among males, team sports showed the highest values for body mass, height, and body fat percentage (%BF), while mesomorphy was greatest in track and field and ectomorphy in sprint events. Among females, track and field athletes presented the highest values for body mass, height, %BF, mesomorphy, and endomorphy, whereas endurance athletes exhibited the highest ectomorphy values. Conclusions: The findings suggest that, compared to international athletes, Mexican athletes exhibited a higher endomorphic component. It is recommended that somatotype assessments should be incorporated into regular monitoring protocols at national sports centers and considered in physical training programs to optimize performance and reduce the risk of injury.

Resistance training (RT) influences endocrine pathways that control skeletal muscle (SM) growth. This review summarizes 25 years of evidence (January 2000–December 2025) from PubMed, Medline, and ScienceDirect, focusing on three aspects: (1) exercise types such as RT, speed, power, high-intensity interval training, and aerobic training at various intensities; (2) dietary factors, including caloric restriction, total protein, protein sources, amino acids, and carbohydrates; and (3) aging-related physiological factors that may impair the insulin/IGF-1 axis in SM, such as insulin resistance, fat infiltration, physical inactivity, mitochondrial dysfunction, and inflammation. The data from Grade A evidence in systematic reviews and RCTs are prioritized to develop practical recommendations and future research directions for young, middle-aged, older, and very old individuals. Evidence regarding the effects of anabolic amino acids in women, middle-aged, and very old individuals, as well as locally mediated IGF-1 effects of any type of exercise, is limited.

Revista oficial de la Sociedad Española de Nutrición Parenteral y de la Sociedad Española de Nutrición. Está dedicada al estudio y divulgación de temas relacionados con la nutrición.

Apply It!: By reading this article, the exercise professionals will learn: • The significance of protein quality and content of protein sources in selecting dietary choices. • A general recommendation for plant-based and animal-based protein intake based on the client profile. • The significance of considering the impact on health and disease risk of healthy/unhealthy choices of both protein sources.