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Introduction: This study examined the responses of physiological and subjective stress to moderateand low-intensity resistance exercise (RE) with total training volumes and inter-set rest equalized, and investigated the repeated measures correlation between physiological stress markers and subjective stress responses. Methods: Eleven young males completed 3 trials in a randomized crossover order, namely-moderate-intensity RE (MOD; 4 sets of 8 repetitions at 85% 8RM), lowintensity RE (LOW; 4 sets of 8 repetitions 15 repetitions at 45% 8RM), and control (CON; resting). Physiological and subjective stress assessments were measured at pre-exercise, immediately postexercise, 30 min post-exercise, and 60 min post-exercise time points. Changes in variables were compared using a linear mixed-effects model. A repeated measures correlation was used to assess the relationships between physiological and subjective stress responses. Results: A higher rating of perceived exertion was observed in the MOD trial (p < .05 vs. LOW). No significant differences were observed in the peak and mean heart rate (p > .05). Higher levels of mental fatigue, physical fatigue, and tension and a lower level of relaxation were only observed immediately after the MOD and LOW trials (p < .05 vs. CON). Cortisol levels during the recovery period were significantly higher in the MOD trial (p < .05 vs. CON), and inhibition of the parasympathetic nervous system (PNS) and activation of the sympathetic nervous system (SNS) during the recovery period were observed in the MOD and LOW trials (p < .05 vs. CON). Increases in lymphocyte counts were observed immediately after exercise in both MOD and LOW trials (p < .05 vs. CON). Subjective feelings were highly associated with change in lymphocyte counts, SNS, and PNS (rrm = .561 to .659, -.519 to -.558; p < .05). Conclusion: These results demonstrate that low-intensity RE under an equal training volume and rest intervals can induce similar physiological stress and subjective feelings when compared to moderate-intensity RE. [ABSTRACT FROM AUTHOR]

Introduction: Adipose tissue and adipose-related inflammatory cytokines are increased with aging, thereby increasing the risk of chronic diseases, such as cardiovascular disease and type 2 diabetes. The effects of resistance training on body fat and adipose-related inflammatory cytokines remain controversial, especially in older adults. The present study investigated the effects of 12 weeks of resistance training on body fat percentage and cytokines in healthy elderly adults. Methods: Nineteen healthy older adults (age: 67.9 ± 3.2 years) without previous experience in resistance training were recruited. The exercise group (EX) performed progressive resistance training (3 times/week), and the control group (CON) maintained their normal lifestyles. The body weight (BW), body mass index (BMI), body fat percentage (BFP), and levels of TNF-α, IL-6, and leptin for the two groups were analyzed by two-way ANOVA. Results: There were no differences in BW or BMI between the EX and CON groups. After resistance training, the BFP and skinfold thickness were significantly decreased in the EX group compared with their own pre-training levels and those of the CON group (p < .05). The serum level of TNF-α in the EX group was also significantly decreased compared with their pre-training level. There were no differences in the serum levels of IL-6 and leptin between the EX and CON groups. Conclusion: Resistance training lowered BFP without changing BW in the EX group, suggesting that age-related increases in BFP were attenuated by the resistance training. Furthermore, the levels of certain serum cytokines tend to decrease with resistance training. Therefore, resistance training could attenuate age-associated chronic inflammation in older adults. [ABSTRACT FROM AUTHOR]