Diabetes is a common chronic disease in clinic, which often occurs in middle-aged and older adults people. Diabetes mellitus is a chronic metabolic disorder resulting from the interaction of environmental, genetic and other factors, characterized primarily by hyperglycemia. The disease is clinically classified into type 1 diabetes and type 2 diabetes mellitus (T2DM), with distinct pathophysiological mechanisms. Type 2 diabetes mellitus accounts for ~90–95% of all diabetes cases worldwide, making it the predominant form of the disease (1). China has gradually entered an aging society, and the prevalence rate of diabetes in the older adults exceeds 20%, which is one of the main factors endangering the health of the older adults (2).

Sarcopenia is one of the common complications in older adults patients with T2DM. Epidemiological studies show that the prevalence of sarcopenia in older adults with T2DM ranges from ~15 to 40%, significantly higher than in age-matched individuals without diabetes (3). Sarcopenia is characterized by progressive loss of skeletal muscle mass and function, leading to reduced physical performance and increased risk of falls and fractures in patients (4). Previous clinical studies have considered (5) that sarcopenia is closely related to human metabolism, especially with diabetic patients. The two promote each other and form a vicious circle, which not only significantly increases the risk of falls and fractures, but also is closely related to cardiovascular events, decreased quality of life and increased mortality. In addition, some studies have shown (6) that sarcopenia is an important complication of diabetic patients and one of the signs of systemic function decline. The prevention and diagnosis of sarcopenia in older adults diabetic patients is helpful to delay the progression of weakness in older adults patients.

The development and maintenance of the musculoskeletal system is significantly influenced by lifestyle factors, particularly physical activity patterns (7). Regular exercise, especially resistance training, stimulates muscle protein synthesis, enhances muscle strength, and may counteract age-related muscle loss, by up-regulating the mTOR–p70S6K pathway, stimulates muscle protein synthesis, and attenuates ubiquitin–proteasome-mediated proteolysis (8, 9). Adequate dietary protein (≥ 0.8 g · kg⁻¹ · day⁻¹) evenly distributed across meals maximizes muscle protein anabolism and provides essential amino acids for reconditioning (10). Beyond exercise and diet, sleep duration and quality influence muscle recovery through nocturnal growth-hormone and testosterone secretion; short or fragmented sleep elevates cortisol, impairs glucose tolerance, and accelerates muscle catabolism (11). Sleep disturbances can induce insulin resistance, elevate inflammatory cytokines (IL-6, TNF-α et al.), and impair muscle recovery (12). Despite established knowledge on individual lifestyle factors (13), the specific interplay between the composite construct of “living habits” [explicitly defined here as the combination of exercise habits, dietary patterns, and sleep behaviors (14)] and physical activity levels with sarcopenia risk in older Chinese adults with T2DM remains incompletely characterized.

In view of this, the present study aims to analyse the relationship between living habits and physical activity and sarcopenia in older adults patients with T2DM. We hypothesize that: (1) Regular exercise habits, a balanced diet, and consistent sleep patterns will be inversely associated with sarcopenia risk; (2) Higher overall physical activity levels [particularly high metabolic equivalent of task (MET) values] will be protective against sarcopenia; and (3) Patients exhibiting a combination of positive lifestyle habits will demonstrate the lowest prevalence of sarcopenia. The findings aim to provide a more comprehensive evidence base for targeted, multifaceted lifestyle interventions in clinical sarcopenia prevention strategies for this vulnerable population.

This cross-sectional study aimed to investigate the association between integrated lifestyle habits—encompassing exercise, dietary patterns, and sleep behaviors—and physical activity levels with sarcopenia risk in Chinese older adults with T2DM. Our key findings demonstrate that regular exercise habits, balanced nutrition, consistent sleep patterns, and higher physical activity levels are significantly associated with reduced sarcopenia prevalence. Multivariate analysis revealed these factors conferred substantial protection, with regular exercise exhibiting the strongest effect (OR = 0.42). These results indicate that older adults T2DM patients with sarcopenia have worse exercise, sleep, diet, and physical activity levels than patients with T2DM alone. This conclusion is basically consistent with previous studies. Lin et al. (29) showed that regular exercise can reduce the risk of sarcopenia in patients with T2DM. Pana et al. (30) found that good sleep quality was negatively correlated with the risk of sarcopenia.

From the mechanism analysis, firstly, the mass, strength and function of human skeletal muscle change constantly during human growth and development, and the state of skeletal muscle remains unchanged or decreases slightly in middle age, and then the muscle mass gradually decreases with age (31). Studies have shown (32) that the pathogenesis of sarcopenia is related to endocrine and metabolic disorders, chronic inflammation and other factors. Exercise has certain anti-inflammatory function, which can affect the level of a series of inflammatory factors, such as inhibiting the expression of tumor necrosis factor α in skeletal muscle, and then exert the effect of promoting protein synthesis, resisting muscle decomposition and enhancing muscle strength (33).

Secondly, patients with less exercise have a relatively higher proportion of connective tissue such as fat in their muscles, and their muscle contractility is significantly reduced (34); In addition, exercise can also stimulate the secretion of irisin, which is involved in the synthesis of brain-derived neurotrophic factor, which can promote skeletal muscle hypertrophy and repair muscle atrophy caused by denervation through autocrine, and achieve a protective effect on skeletal muscle (35). Thirdly, lack of sleep or sleep disorders can cause stress reaction in patients, activate the hypothalamus-pituitary-adrenaline axis, and then excite sympathetic nerves, cause insulin resistance and reduce insulin sensitivity, and then reduce insulin levels, ultimately leading to decreased muscle protein synthesis, leading to the risk of sarcopenia (36).

Finally, food intake is also associated with sarcopenia, and whether too much or too little food intake can affect the skeletal muscle of patients; Less intake of protein, unsaturated fatty acids and vitamin D deficiency not only affect the sleep quality of patients, but also lead to the decrease of muscle synthesis, resulting in the risk of sarcopenia (37–39).

Our findings align with recent systematic reviews and meta-analyses that consistently demonstrate the protective effects of regular physical activity against sarcopenia in older adults with T2DM. A Bayesian network meta-analysis showing that combinations of resistance training prescription could improve muscle strength and hypertrophy (40). Similarly, Izquierdo et al. emphasized that the protective effects of exercise on muscle health operate through multiple pathways, including improved insulin sensitivity, reduced inflammation, and enhanced myokine production (41). While our cross-sectional study cannot establish causality, the observed associations are consistent with these proposed mechanisms and highlight the potential for lifestyle interventions in clinical practice. The clinical implications of our findings are significant for the development of sarcopenia prevention strategies in older adults with T2DM. Clinicians should routinely assess lifestyle habits and physical activity levels during regular diabetes follow-up visits. This could involve implementing standardized screening tools for sarcopenia risk that incorporate lifestyle factors as predictors. Furthermore, individualized exercise prescriptions that consider the patient's physical capabilities and preferences would likely yield better adherence. The relationship between sleep quality and sarcopenia revealed in our study suggests that sleep health education should be integrated into diabetes management programs. Additionally, nutritional counseling focusing on adequate protein intake (0.8–1.2 g/kg/day) and optimal distribution throughout the day may help counteract the accelerated muscle loss in this population. A multidisciplinary approach involving endocrinologists, physical therapists, exercise physiologists, nutritionists, and sleep specialists would be ideal for comprehensive intervention.

Based on the results and mechanism of action of this study, the following preventive measures should be taken: (1) Encourage patients to engage in regular exercise, with an emphasis on progressive resistance training combined with moderate-intensity aerobic exercises. While low-intensity activities such as walking and Tai Chi may be appropriate starting points for deconditioned individuals, progression to resistance training is important for optimal muscle health as recommended by recent consensus guidelines (41); (2) Maintain regular work and rest and ensure 7–9 h of quality sleep every night; (3) Pay attention to a balanced diet and appropriately increase the intake of high-quality protein and vitamin D; (4) Make an appropriate physical activity plan according to individual circumstances. This study still has the following limitations: (1) The sample size is too small, which may affect the stability of statistical results; (2) It is a single-center study, and the extrapolation of the results needs to be verified; (3) Without long-term follow-up of patients, the effect of intervention measures cannot be evaluated. Though our sample size met the minimum statistical requirements based on power analysis, we acknowledge that the relatively small sample size (n = 65) may limit the generalizability of our findings. Future studies with larger samples are needed to validate our results. Therefore, it is suggested that a large sample and multi-center prospective cohort study should be carried out in the future to further verify the conclusion of this study.

This study found that lifestyle habits and physical activity levels are significantly associated with sarcopenia in older adults with T2DM. Regular exercise, regular sleep patterns, balanced diet, and high physical activity levels were associated with lower risk of sarcopenia in this population. These findings suggest that assessing lifestyle habits and physical activity levels may help identify patients at risk of sarcopenia, and promoting healthy lifestyle behaviors could potentially reduce sarcopenia risk in older adults with T2DM. Future larger-scale, prospective studies are needed to further validate these findings and explore the effectiveness of targeted interventions. Therefore, the risk of sarcopenia can be identified clinically by assessing these lifestyle habits and physical activity levels of patients, and then appropriate preventive measures, such as encouraging moderate exercise, maintaining regular routines, and eating a balanced diet, can be taken to reduce the risk of sarcopenia.