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Introduction. The time of exercise (morning and afternoon) can lead to changes in hormonal responses and exercise performance. Aim of Study. The current study aimed to investigate the effects of morning vs afternoon high-intensity interval training (HIIT) on testosterone (T), cortisol (C) and the testosterone/cortisol (T/C) ratio in active men. Material and Methods. Eleven active male students (aged: 19.0 ± 1.0 yrs., height: 177.5 ± 9.0 cm, weight: 70.6 ± 8.3 kg and BMI: 22.19 ± 1.88 kg/m2) completed two trials of the 40-m maximal shuttle run test (which incorporates 5 × 40 m shuttle sprints with 30 s between the start of each sprint), with seven days between the trials. All the trials were conducted indoors. Blood samples were taken before and immediately after each exercise session from the antecubital vein by repetitive venous puncture in a sitting position. Results. Data evidenced that the T concentration increased after HIIT in the afternoon (pre: 9.86 ± 0.42 vs post: 10.3. ± 0.61, P = 0.02). The significant difference was observed between pre-tests (T: 10.4 ± ± 0.67 vs 9.86 ± 0.42, P = 0.009; C: 898.38 ± 199.51 vs 355.53 ± 92.95, P = 0.001; T/C ratio: 0.012 ± 0.002 vs 0.03 ± 0.012, P = 0.001) and also post-test (T: 10.68 ± 0.53 vs 10.3. ± 0.61, P = 0.01; C: 990.64 ± ± 293.07 vs 452.73 ± 307.34, P = 0.001; T/C ratio: 0.011 ± 0.003 vs 0.056 ± 0.065, P = 0.04). Conclusions. It seems that performing high-intensity interval training (HIIT) in the afternoon may be more suitable in terms of the level of anabolic processes. [ABSTRACT FROM AUTHOR]

Background Acute beetroot juice (BJ) intake has shown to enhance aerobic and anaerobic performance. However, no studies have evaluated the effects of BJ intake on CrossFit (CF) performance by linking hormonal, metabolic, and mechanical responses. The purpose of this study was to determine the causal physiological association between hormonal, metabolic and mechanical responses, and CF workouts performance after acute BJ intake. Methods Twelve well-trained male practitioners undertook a CF workout after drinking 140 mL of BJ (~ 12.8 mmol NO3 −) or placebo. The two experimental conditions (BJ or placebo) were administered using a randomized, double-blind, crossover design. The CF workout consisted of repeating the same exercise routine twice: Wall ball (WB) shots plus full back squat (FBS) with 3-min rest (1st routine) or without rest (2nd routine) between the two exercises. A 3-min rest was established between the two exercise routines. Results An interaction effect was observed in the number of repetitions performed (p = 0.04). The Bonferroni test determined a higher number of repetitions after BJ than placebo intake when a 3-min rest between WB and FBS (1st routine) was established (p = 0.007). An interaction effect was detected in cortisol response (p = 0.04). Cortisol showed a higher increase after BJ compared to placebo intake (76% vs. 36%, respectively). No interaction effect was observed in the testosterone and testosterone/cortisol ratio (p > 0.05). A significant interaction effect was found in oxygen saturation (p = 0.01). A greater oxygen saturation drop was observed in BJ compared to placebo (p

Background: Acute beetroot juice (BJ) intake has shown to enhance aerobic and anaerobic performance. However, no studies have evaluated the effects of BJ intake on CrossFit (CF) performance by linking hormonal, metabolic, and mechanical responses. The purpose of this study was to determine the causal physiological association between hormonal, metabolic and mechanical responses, and CF workouts performance after acute BJ intake. Methods: Twelve well-trained male practitioners undertook a CF workout after drinking 140 mL of BJ (~ 12.8 mmol NO3−) or placebo. The two experimental conditions (BJ or placebo) were administered using a randomized, double-blind, crossover design. The CF workout consisted of repeating the same exercise routine twice: Wall ball (WB) shots plus full back squat (FBS) with 3-min rest (1st routine) or without rest (2nd routine) between the two exercises. A 3-min rest was established between the two exercise routines. Results: An interaction effect was observed in the number of repetitions performed (p = 0.04). The Bonferroni test determined a higher number of repetitions after BJ than placebo intake when a 3-min rest between WB and FBS (1st routine) was established (p = 0.007). An interaction effect was detected in cortisol response (p = 0.04). Cortisol showed a higher increase after BJ compared to placebo intake (76% vs. 36%, respectively). No interaction effect was observed in the testosterone and testosterone/cortisol ratio (p > 0.05). A significant interaction effect was found in oxygen saturation (p = 0.01). A greater oxygen saturation drop was observed in BJ compared to placebo (p < 0.05). An interaction effect was verified in muscular fatigue (p = 0.03) with a higher muscular fatigue being observed with BJ than placebo (p = 0.02). Conclusions: BJ intake improved anaerobic performance only after the recovery time between exercises. This increase in performance in the first routine probably generated greater hypoxia in the muscle mass involved, possibly conditioning post-exercise performance. This was observed with a fall in oxygen saturation and in muscle fatigue measured at the end of the CF workout. The greatest perceived changes in cortisol levels after BJ intake could be attributed to the nitrate-nitrite-nitric oxide pathway. [ABSTRACT FROM AUTHOR]

Endogenous hormones are essential for physiological reactions and influence the adaptation to weightlifting training by modulating anabolic and catabolic processes. It seems that testosterone and cortisol are playing a key role in anabolic and catabolic processes in resistance training. Eight elite Czech and Slovak weightlifters volunteered in present study. The testosterone and cortisol were measured in 4 testing sessions over 18 weeks during preparation and competition period. The training protocol consisted of three specific weightlifting exercises. The saliva samples were collected in 4 testing sessions, pre and 5 min, 15 min and 30 min after protocol, respectively. The basal level of salivary testosterone and cortisol remains unchanged during preparation and competition period. Also, acute testosterone response was not observed over the monitored period. However, acute decrease of cortisol were found between pre intervention and post 5 (p ≤ 0.01), 15 (p ≤ 0.01), and 30 min (p ≤ 0.05) during preparation periods. While in competition period was found significant decrease (p ≤ 0.05) only 5 min after testing protocol. The testosterone/cortisol ratio significantly increased during preparation periods (p ≤ 0.01), but not in competition period. Results indicated that the routine assessment of testosterone and cortisol may provide an effective way to monitor acute and chronic adaptive response to weightlifting training. Our results suggest that cortisol, not the testosterone is an important component of adaptation during elite weightlifting training. [ABSTRACT FROM AUTHOR]

Recently, cortisol has been suggested to moderate the positive relationship between testosterone and antisocial behavior. More precisely, high testosterone levels have been found to be related to aggressive or dominant behavior especially when cortisol levels were low. In the present study, we aimed to extend these findings to pro-environmental behavior as an indicator of prosocial behavior. In a first step, 147 male participants provided information on their everyday pro-environmental behavior by completing an online questionnaire on various energy-saving behaviors. In a second step, subjects provided two saliva samples for the assessment of testosterone and cortisol on two subsequent mornings after awakening. We found that testosterone was negatively related to pro-environmental behavior, but only in men with low cortisol. In conclusion, our findings provide first evidence for the joint association of testosterone and cortisol with everyday pro-environmental behavior. These results further reinforce the importance of considering interdependent hormone systems simultaneously rather than focusing on a single hormone. [ABSTRACT FROM AUTHOR]

Summary: Objectives: To investigate the effects of a 12-week training program on the hormonal concentrations and physiological performances of soccer players. Equipment and methods: Eighteen subjects were evaluated at the beginning (T1), in the middle (T2) and at the end (T3) of the season. They had their blood collected for the analysis of cortisol, testosterone, testosterone/cortisol ratio, epinephrine and norepinephrine. The lactic and alactic anaerobic parameters and the anaerobic threshold were used as measures of physiological performance. Results: While cortisol levels were higher in T2 and T3 compared to T1 (P ≤0.05), the testosterone values and the testosterone/cortisol ratios were significantly lower in T2 and T3 compared to T1 (P ≤0.05). Norepinephrine concentrations increased from T1 to T2 and T3 (P ≤0.05). In addition, while the alactic anaerobic performance parameters decreased significantly in T2 and T3 compared to T1 (P ≤0.05), the anaerobic threshold increased in T2 and T3 in comparison with T1 (P ≤0.05). In summary, we verified that NE levels might be used as sensitive markers for variations of volume and intensity of training. In addition, the changes in the levels of the selected hormones measured in the current study were not associated to negative responses of the physiological performances. [ABSTRACT FROM AUTHOR]