In modern sports, competitions where weight categories determine eligibility (e.g., wrestling, judo, boxing, taekwondo, etc.), characterized by frequent physical contact, and where athletes strive to exceed their maximum physical capabilities, especially female athletes, changes in body composition can significantly impact athletic performance and competitiveness (Chaabene et al., 2017). Body composition includes body weight, height, muscle mass, lean body mass, and body fat percentage. The most critical factor for overweight athletes is body fat percentage, as it changes with age and sex, having a significant relationship with athletic performance and competitiveness. These relationships are particularly evident in female athletes with high body fat percentages. As body fat percentage increases, there is a relatively higher accumulation of fat, which can adversely affect the respiratory, circulatory, and muscular systems, thereby impairing athletic performance. An increase in body fat percentage can elevate the activity of inflammatory cells within the bloodstream, thereby increasing the response of inflammatory factors. Such an increase in body fat percentage increases the likelihood of being overweight and elevates inflammatory marker levels and metabolic risk factors within the body, consequently decreasing athletic performance (Ellulu et al., 2017). Moreover, with increasing research on exercise-related topics, studies investigating the expression of inflammatory markers have gained momentum, with particular attention being paid to C-reactive protein (CRP) and tumor necrosis factor-alpha (TNF-α).

CRP is produced in the body when inflammation occurs as a marker of systemic inflammatory response (Zhao et al., 2023). It is an acute-phase reactive protein generated in response to inflammatory cytokines, such as interleukin-6 (IL-6), produced by macrophages and adipocytes, and is subsequently released into the bloodstream (Ellulu et al., 2017). Increased CRP levels in the blood increase cholesterol levels and reduce high-density lipoprotein cholesterol levels, thus declining vascular endothelial cell function and affecting muscle endurance and strength. Additionally, CRP has been suggested as a contributing factor to cardiovascular issues and has been reported to be closely associated with metabolic processes and athletic performance among athletes (Romero-Elías et al., 2022). TNF-α, classified as an inflammatory factor, regulates CRP synthesis in the liver and inhibits insulin action in skeletal muscles (Zhao et al., 2023). Adipocytes secrete TNF-α and IL-6, a primary inducer of CRP in the liver. Approximately 30% of secreted IL-6 is produced in adipose tissue, with visceral adipose tissue secreting more IL-6 than subcutaneous adipose tissue, and visceral adipose tissue having a strong correlation with CRP levels (Chait and den Hartigh, 2020). Increased serum TNF-α levels can impair glycemic control, insulin resistance (IR), and metabolic function of blood lipids, as well as inhibit the activity of lipoprotein lipase enzymes and stimulate lipid synthesis in the liver (Zhao et al., 2023). High-intensity exercise can promote anti-inflammatory effects in skeletal muscles and adipose tissue, increase athletic performance, and decrease inflammatory marker levels (Li et al., 2022).

However, previous literature has reported contradictory and inconsistent results regarding the effects of exercise intensity training and type on inflammatory markers (Baygutalp et al., 2021). Circulating triglycerides and high glucose concentrations in the bloodstream can result in sustained storage of triglycerides and glucose. Consequently, the mobilization capacity of muscle cells decreases, leading to IR (Li et al., 2022). In athletes, IR, overweight, and hyperglycemia can damage muscle cells, decreasing muscle strength, endurance, and athletic performance (Merz and Thurmond, 2020). Research on exercise modalities and training methods for improving IR is abundant. The effects of reducing body fat percentage and the benefits of prolonged aerobic training (AT) and resistance training (RT) have been reported (DiMenna and Arad, 2020). However, effective exercise strategies have not been investigated in detail. Aerobic and resistance exercises have been reported to be effective in reducing body fat and maintaining exercise capacity in athletic wrestlers (Francino et al., 2022). Adipose tissue is recognized as an endocrine organ, regulating fat cell metabolism through complex interactions between various endocrine mediators and the sympathetic nervous system (Poulos et al., 2010).

Exercise in the postprandial state promotes the uptake of glucose and fatty acids, suppresses triglyceride lipolysis, and creates an imbalance of energy expenditure (Harris and Kuo, 2021; Winnick et al., 2008). Appropriate exercise interventions should stimulate lipid catabolism and appropriate aerobic and resistance exercises have been reported to lead to maximal lipid oxidation during endurance training (Ribeiro et al., 2015; Zhao et al., 2023). However, evidence supporting these findings remains unclear. Increased insulin sensitivity is often accompanied by improved insulin signaling due to increased aerobic exercise (Li et al., 2022). However, previous research has reported that insulin receptor activation is not expressed in short-term, high-intensity exercises in skeletal muscles (Merz and Thurmond, 2020). Nevertheless, Winnick et al. (2008) reported that short-term exercise alone enhanced insulin responsiveness, with observed differences based on type of exercise. While findings regarding the impact of exercise type remain controversial across various studies, reduction in adipose tissue triacylglycerol level subsequent to exercise has gained attention among researchers due to mechanisms suggested to accelerate fat breakdown. To the best of our knowledge, no studies to date have directly compared the efficacy of individual exercise modalities versus combined aerobic and resistance exercises. Despite recent endeavors to scientifically explore the effects of each exercise type, fundamental research remains inadequate.

Therefore, this study aimed to scientifically identify internal physiological changes caused by aerobic and resistance exercise alone or in combination and to confirm the effects on inflammatory markers in female wrestlers. Our findings may provide preliminary evidence for designing appropriate training programs and protocols to support athletic performance.

Being overweight is common among female wrestlers. Reduction in body fat mass and increase in lean body mass have been associated with enhanced metabolic function and athletic performance, significantly impacting overall performance (Jagim et al., 2024). Consequently, attention is often directed toward IR and inflammatory markers in female wrestlers. High-intensity exercise can reduce body fat percentage and cause rapid decrease in blood sugar levels (Cassidy et al., 2017). This decrease promotes the development of muscle and intramuscular adipose tissue, resulting in improved hemodynamic function and enhanced basal metabolic rate, thus positively affecting the body’s internal milieu (Ashcroft et al., 2024).

In this study, following 12 weeks of high-intensity exercises, including aerobic exercise, resistance exercise, and combined exercise programs, all groups exhibited a decreasing trend in body fat percentage. However, statistically significant differences were observed, with a notably greater reduction in body fat percentage in the AEG compared to the REG and the CEG. In a study by Ho et al. (2012), conducted over 12 weeks, all groups, including AT, RT, and CEG, experienced reductions in waist circumference and fat mass, alongside increased maximal oxygen consumption. In the RT and CEG groups, an increase in muscle thickness was reported. Conversely, Khodadadi et al. (2023) reported positive effects on strength and fat mass reduction solely in the high-intensity resistance group following high-intensity exercise. Contrasting results were reported by Yu et al. (2022), who conducted an 8-week study on high-intensity RT, revealing reductions in body fat percentage, improvements in metabolic blood parameters, and enhancements in body composition. These findings underscore variations in exercise intensity assessment due to differing program durations, protocols, and participant profiles. The mechanism underlying the observed reduction in body fat percentage, consistent with findings of previous studies, may be attributed to improved blood flow and reduced vascular resistance induced by 12 weeks of high-intensity aerobic exercise among overweight female wrestlers. This enhancement in cardiovascular function may activate metabolic processes, leading to increased basal metabolic rate, thus highlighting the beneficial effects of training (Cassidy et al., 2017). These mechanisms reinforce our study’s findings and previous findings, suggesting that high-intensity aerobic exercise for 12 weeks or longer should be regarded as a crucial factor in improving athletic performance and metabolic function among overweight female wrestlers striving to enhance their performance through exercise.

IR is a persistent condition characterized by storage of triglycerides and glucose, influenced by circulating triglycerides and elevated glucose levels (Li et al., 2022). Among athletes, the primary concern associated with IR is the diminished functionality of muscle cells. Increasing exercise intensity improves insulin sensitivity and insulin signaling (Merz and Thurmond, 2020; Swift et al., 2018). However, during sudden escalations in exercise intensity, activation of insulin receptors in skeletal muscles may not be adequately expressed. Nevertheless, regular exercise enhances insulin sensitivity (DiMenna and Arad, 2020). Conversely, Winnick et al. (2008) reported heightened insulin responsiveness following short-term exercise alone. Furthermore, while there is debate regarding exercise intensity across various research studies, the reduction in triacylglycerol content in adipose tissue following high-intensity exercise is attributed to mechanisms that expedite fat breakdown (Harris and Kuo, 2021). This study showed significant differences in timing, groups, and interactions within the REG. High-intensity resistance exercise demonstrated improvements in insulin sensitivity and enhanced blood glucose response. Similar glucose processing mechanisms were observed in previous studies involving athletes. For instance, Hansen et al. (2012) study on bodybuilders employing resistance exercise reported higher glucose tolerance and improved insulin action compared to the control group. Moreover, high-intensity resistance exercise improved insulin sensitivity and glucose tolerance in obese and overweight women. Some studies have indicated reduction in IR solely attributable to the effects of resistance exercise, independent of changes in aerobic capacity, body weight, or body composition (Lee et al., 2019). These findings support the significant decrease observed in our study’s high-intensity REG. Swift et al. (2018) study reported a decrease in IR in the high-intensity REG compared with that in the high-intensity AEG, without initial weight loss. Over time, the high-intensity REG exhibited a consistent trend of decreasing IR compared with that in the high-intensity AEG. Changes in muscle mass size occur due to increased muscle mass, leading to modifications in glucose disposal rate, which is associated with metabolic activation, elevated protein content of GLUT-4, and enzyme activation, consequently reducing IR (Merz and Thurmond, 2020). However, a significant decrease in the high-intensity AEG, observed in previous studies, was not evident in this study. This discrepancy may be attributed to sequential changes in mechanisms following moderate to low-intensity exercise, which did not yield significant differences in glucose tolerance after high-intensity aerobic exercise. Therefore, it is recommended to incorporate high-intensity RT for overweight female wrestlers to improve athletic performance, promote recovery, and improve metabolic function through effective alterations in IR.

In athletes, inflammatory markers instigate a continuous increase in reactive species (reactive oxygen species and reactive nitrogen species) as the intracellular antioxidant defense system weakens (Clemente-Suárez et al., 2023). This escalation in reactive species prompts hyper-activation of macrophages and immune system functions during the inflammatory process. These activated inflammatory factors perpetuate chronic inflammation and disrupt normal bodily functions, resulting in reduced postexercise recovery and musculoskeletal-related diseases (Kunz and Lanza, 2023). CRP, TNF-α, and IL-6 are adipocytokines associated with inflammatory responses. Elevated levels of these markers are known to correlate with increased body fat, particularly abdominal fat, and decreased lean body mass. They serve as indicators of inflammatory conditions such as hypertension, atherosclerosis, and IR (Al-Mansoori et al., 2022). CRP, an acute-phase reactant, is synthesized by the liver and adipose tissue in response to inflammation in the body (Romero-Elías et al., 2022). Elevated CRP levels in the bloodstream correlate with IR and skeletal muscle activation, contributing to diminished athletic performance and an increased risk of musculoskeletal injuries in athletes (Ribeiro et al., 2015). Previous studies investigating changes in blood CRP concentration based on exercise type have demonstrated that both aerobic and resistance exercises significantly reduce CRP levels (Al-Mansoori et al., 2022; Ribeiro et al., 2015). Flynn et al. (2007) study suggested that regular exercise exerts a structural anti-inflammatory effect, lowering CRP levels and impacting cardiovascular health by reducing risk factors. However, some studies have also reported that moderate- to low-intensity exercise may compromise vascular elasticity and heighten the likelihood of inflammation-related complications (Zhang et al., 2021). Conversely, high-intensity exercise or above has a positive impact on reducing blood CRP levels and anti-inflammatory effects, leading to a significant decrease in CRP concentration. This effect is further enhanced with long-term exercise. Cerqueira et al. (2020) study reported a decrease in blood CRP levels after high-intensity exercise, while Taylor et al. (2022) study yielded controversial results, indicating an increase in blood inflammatory substances such as CRP, TNF-α, and IL-6 after high-intensity exercise. Discrepancies in these studies may stem from variations in exercise duration and exercise type. Our study revealed a statistically significant difference in the CEG group after 12 weeks of exercise, aligning with findings of previous research on the reduction in CRP levels postexercise, depending on the duration and type of exercise.

Long-term high-intensity combined exercise enhances cardiac output, leading to increased tissue blood flow and shear stress on the blood vessel wall (Taylor et al., 2022). Reduced platelet activity due to planar friction inhibits clot formation and platelet adhesion while promoting blood vessel dilation. This process improves inflammatory indicators by further activating blood vessel function, thereby reducing inflammatory responses and blood clot formation around vessels (Periayah et al., 2017; Taylor et al., 2022). IL-6, a multifunctional cytokine crucial in regulating immunity and inflammation, exhibits dynamic fluctuations during and after exercise, influenced by factors such as exercise intensity, duration, and muscle mass. IL-6 concentrations increase rapidly after moderate-intensity dynamic exercise (Cerqueira et al., 2020). In our study, the CEG group showed a significant decrease in IL-6 levels after 12 weeks of exercise. These findings suggest that changes in IL-6 levels post-high-intensity exercise are influenced by baseline values, exercise duration, and exercise frequency. Elevated IL-6 levels are commonly observed in individuals with exercise experience, those with underlying health issues, and non-athletes (Jouffroy et al., 2022). Thus, the findings of this study corroborate the decrease in IL-6 levels observed following high-intensity compound exercises in athletes. TNF-α, a cytokine produced during inflammatory responses, directly contributes to impaired insulin signaling and diminished muscle glucose uptake. Elevated TNF-α levels are closely linked to IR (Zhao et al., 2023). Significant differences were observed in the CEG group after 12 weeks of exercise. It was noted that the increase in muscle mass resulting from high-intensity exercise contributed to the reduction in TNF-α levels, whereas no significant change was observed with short-term or low-to-moderate-intensity exercise. Previous studies have reported a lack of TNF-α decrease in combined endurance, balance, and flexibility exercises, which are influenced by exercise intensity, level, and duration (Baygutalp et al., 2021). The decrease observed after high-intensity compound exercises in this study could provide physiological evidence for shortened recovery time and reduced injury exposure in athletes postexercise. Therefore, considering each variable, the type and duration of high-intensity exercise play a crucial role in significantly reducing CRP, IL-6, and TNF-α levels (Cassidy et al., 2017; Cerqueira et al., 2020). These factors should be considered essential in effective exercise interventions for altering inflammatory markers in overweight female wrestlers.

This exploratory study provided clinical evidence that a 12-week, high-intensity exercise regimen (50 min per day) improves various physiological parameters in overweight female wrestlers. According to the study results, all exercise groups demonstrated positive changes, with specific advantages observed in different parameters depending on the exercise type. After 12 weeks, significant reductions in body weight and body fat were observed across all groups, with the AEG showing the most substantial decreases. IR improved significantly in all groups, with the REG demonstrating the most notable improvements. Inflammatory markers (TNF-α, IL-6, and CRP) decreased in all groups, with the CEG exhibiting significantly lower levels compared to the other groups. These findings suggest that each type of exercise offers specific benefits: aerobic exercise for body composition management, resistance exercise for improving insulin sensitivity, and combined exercise for reducing inflammatory markers. The exercise programs implemented in this study may contribute to enhancing athletic performance, recovery, and metabolic health in overweight female wrestlers. Coaches and athletic trainers should consider these differential effects when designing training programs tailored to specific physiological goals for wrestlers.