Journal of Exercise & Organ Cross Talk

Abstract This study examined the acute hormonal and myokine responses to traditional and circuit resistance training in young males with distinct BMI-based groups. Twenty sedentary men aged 20–30 years were classified as high-BMI (BMI >29.9) or low-BMI (BMI <18.5). Each participant completed both traditional resistance training (TRT) and circuit resistance training (CRT) protocols in a crossover design, with a one-week washout period. Sessions included multi-joint upper and lower body exercises at comparable intensities. Blood samples were taken immediately before and after each session. Serum levels of testosterone, cortisol, myostatin, and follistatin were assessed using ELISA kits. A repeated-measures ANOVA was used to compare within- and between-group changes across time and training modality. Baseline cortisol levels were significantly higher in low-BMI individuals (P=0.037), while testosterone levels showed no initial difference between groups (P>0.05). Post-TRT, testosterone levels increased significantly in high-BMI individuals compared to low-BMI individuals (P=0.017), with both training types elevating testosterone and cortisol across all participants (P<0.05). CRT led to a significant reduction in myostatin and increase in follistatin in high-BMI individuals (P<0.05), while only follistatin increased significantly in low-BMI individuals after TRT (P<0.05). These results suggest that CRT promotes superior anabolic signaling in high-BMI individuals, while TRT is more effective at enhancing testosterone response. Myokine and hormonal responses appear to be body-type-dependent and training-modality-specific. Practitioners designing hypertrophy-focused programs should tailor training protocols to the athlete’s BMI-based group to optimize muscle adaptation and endocrine outcomes. And also, trainers should individualize hypertrophy programs based on body composition to optimize both hormonal responses and muscle adaptation.

Abstract The study aimed to compare the acute effects of low resistance exercises with partial and complete blood flow restriction (BFR) and heavy resistance exercise on growth hormone (GH), myostatin, testosterone, and cortisol in competitive wrestlers. Forty elite wrestlers were randomly divided into four groups (n=10); low resistance training with complete BFR (LRT+CBFR), low resistance training with partial BFR (LRT+PBFR), low resistance training (LRT), and heavy resistance training (HRT). Blood samples were collected before and after the intervention, and a specific ELISA kit measured variables. Analysis of covariance and paired t-test was performed to analyze the data. There were no significant differences in the variables between the four interventions. Intra-group results showed a significant decrease in myostatin levels in the HRT group (p=0.02), and a significant increase in GH in the LRT+CBFR (p=0.02) and LRT+PBFR (p=0.03), testosterone in the HRT group (p=0.04) and cortisol in the three groups LRT+CBFR (p=0.02), LRT+PBFR (p=0.01) and HRT (p=0.04). Despite the similarity of the changes in the four interventions, due to the percentage of changes, it seems that low resistance training with BFR could produce similar anabolic effects to high-intensity resistance training.

Abstract The current study aimed to compare the effect of hypertrophy-, strength-, and power-type resistance exercise in resistance-trained women with considering cortisol and androgen cross talk. After one-repetition maximum (1-RM) estimation, ten resistance-trained women (age: 26.30 ± 4.95 years; body mass index: 22.07 ± 2.02 kg/m2; body fat: 24.64 ± 4.98%) conducted hypertrophy- (70% of 1-RM), strength- (90% of 1-RM), and power-type (45% of 1-RM) resistance exercise for three consecutive weeks. The movements included lever leg extension, reverse-grip lat pull-down, horizontal leg press, standing biceps cable curl, lying leg curl, machines bench press, standing cable triceps extension, and seated calf raises. Fasting blood was taken before and immediately after each trial. Statistical analyses were performed at a significance level of P

Abstract Puberty with interactive growth in tissues is a sensitive period in life that can be more affected by obesity. Also the increase of leptin and insulin resistant independent of obesity have been seen in puberty. The aim of our study was to investigate the role of puberty on changes in leptin, testosterone, and insulin resistance in sedentary obese boy with considering possible crosstalk between leptin and insulin resistance. 58 sedentary obese boys (14.10 + 1.37 years) participated in this study. Tanner stage scales were used to measure puberty by self-reporting. Initially anthropometric characteristics and then, fasting serum’s glucose, insulin, leptin and testosterone, were measured. With increasing mature from TS2 to TS5, the increasing of testosterone, body mass and lean body mass and the reduction of body fat percentage were significantly (p≤0.05). but the changes in leptin and HOMA-IR were not significant. However, the decreased leptin after adjusting for BMI between TS3 and TS4 were significant (p≤0.05). During puberty, rapid growth in muscle tissue were associated with decreased body fat percent, serum leptin and insulin resistance. Among the possible reasons is a 15-fold increase in serum testosterone from TS2 to TS5. These changes reflect the cross talk between muscle and adipose tissue by hormonal mediators.