Hormonal response after masturbation in young healthy men – a randomized controlled cross-over pilot study

Background Hormones like testosterone play a crucial role in performance enhancement and muscle growth. Therefore, various attempts to increase testosterone release and testosterone concentration have been made, especially in the context of resistance training. Among practitioners, sexual activity (coitus and masturbation) a few hours before training is often discussed to result in increases of testosterone concentration and thus promote muscle growth. However, there is no evidence to support this assumption and the kinetics of the testosterone and cortisol response after sexual activity have not been adequately investigated. Therefore, the aim of this pilot-study was to examine the kinetics of hormone concentrations of total testosterone, free testosterone and cortisol and their ratios after masturbation. In a three-arm single blinded cross-over study, the effects of masturbation with visual stimulus were compared to a visual stimulus without masturbation and the natural kinetics in healthy young men. Results The results showed a significant between-condition difference in free testosterone concentrations. Masturbation (p < 0.01) and a visual stimulus (p < 0.05) may seem to counteract the circadian drop of free testosterone concentrations over the day. However, no statistical change was observed in the ratios between total testosterone, free testosterone and cortisol. Conclusions It can be assumed that masturbation may have a potential effect on free testosterone concentrations but not on hormonal ratios. However, additional studies with larger sample sizes are needed to validate these findings.

Characteristics of Libido and Testosterone Concentration of Polled and Horned Bali Bulls after GnRH Injection

Bali cattle are one of the original Indonesian germplasm, which in its development were found to be hornless or polled. Polled are Balinese cattle whose horns do not grow naturally, but have the same characteristics as those with horns. However, there are indications that polled have a lower libido. The purpose of this study was to determine the characteristics of libido and testosterone concentration after gonadotrophin releasing hormone (GnRH) injection. In this study each of 7 male polled and horned Bali cattle aged 3.5-6 years were used. Libido characteristics were observed by recording the first time the male fondled the teaser until ejaculation, while the testosterone concentration was measured using blood plasma taken on day 0 or before injection, day 7^th, and day 14^th after GnRH injection. Testosterone analysis used enzyme linked immunosorbent assay (ELISA) method. The results showed that the libido of polled was not different (P&gt;0.05) compared to that of the horned on the 0, 7^th and 14^th days after GnRH injection. However, in polled on the 7^th day after GnRH injection, it was significantly lower than on day 0 and 14, but on day 0 it was not different with day 14. Testosterone concentration on day 7 after injection of GnRH was not different (P&gt;0.05) compared to day 0 both in polled and horned bulls, but on day 14 after injection was significantly higher (P&lt;0.05) in horned than polled. In conclusion, polled and horned Bali bulls had high libido with a score of +1, but on the 7^th day after GnRH injection, polled had lower libido than horns. The testosterone concentrations of polled and horned on day 7 after GnRH injection were not different compared to day 0, while the 14^th day was higher in horned bull.

Systematic review and meta-analyses on associations of endogenous testosterone concentration with health outcomes in community-dwelling men

ObjectivesThe overall study aim is to clarify the relation of endogenous sex hormones with major health outcomes in men. This paper reports a systematic review focusing on published estimates for testosterone associations.SettingCommunity-dwelling men.Participants20 180 adult men participated in the final set of studies identified and selected from a systematic review. Eligible studies included prospective cohort studies with plasma or serum testosterone concentrations measured for adult men using mass spectrometry with at least 5 years of follow-up data and one of the specified outcome measures recorded. Only published or grey literature items written in English were considered.Primary and secondary outcome measuresPlanned prospective outcome measures: cardiovascular disease (CVD) events, CVD deaths, all-cause mortality, cancer deaths, cancer diagnoses, cognitive decline, dementia. Meta-analyses were of the most frequently reported outcomes in selected studies: CVD deaths and all-cause mortality. Succinct characterisations of testosterone associations with other outcomes are also presented.ResultsScreening of 1994 deduplicated items identified 9 suitable studies, with an additional 2 identified by colleagues (11 in total). Summary estimates of mean testosterone concentration and age at recruitment for 20 180 adult men were 15.4±0.7 nmol/L and 64.9±3.3 year. Despite considerable variation in mean testosterone, a metaregression estimated no significant dependence on mean age at recruitment among studies (slope=−0.03, 95% CI −0.11 to 0.06). Meta-analyses demonstrated negligible heterogeneity and no significant effect of a 5 nmol/L increase in testosterone on the risk of all-cause mortality (HR=0.96, 95% CI 0.89 to 1.03) or death from CVD (HR=0.95, 95% CI 0.83 to 1.08).ConclusionsAnalyses of published estimates did not demonstrate associations of endogenous testosterone with CVD deaths or with all-cause mortality. Suggested further research includes the planned individual participant data meta-analyses for selected studies, enabling the investigation of non-linear summary effects.PROSPERO registration numberPROSPERO: CRD42019139668.

Double-Blind, Placebo-Controlled Trial of Cyproterone Acetate to Prevent Flare-Up Effect on Dogs Implanted With Deslorelin

Deslorelin slow-released implants are registered in Europe for the reversible suppression of fertility in male dogs. After administration, a time-limited increase in sex hormones concentration and related behavioral problems may be observed. The aim of this work was to assess whether cyproterone acetate, a synthetic progestogen, can prevent this flare-up effect. Eighteen privately-owned entire male dogs were enrolled in this double-blind, placebo-controlled, randomized clinical trial. All subjects received a 4.7 mg deslorelin implant by SC route and 1–3 capsules containing either cyproterone acetate 2 mg/kg (N = 9) or a placebo (N = 9), by oral route BID for 14 days, depending on the dog's weight. The dogs were followed for 28 days. An increase in the blood testosterone concentration was observed in respectively 9/9 and 7/9 dogs of the control and cyproterone groups (p = 0.47). However, a worsening of the sex hormone related problems (i.e., urinary marking, mounting, aggressiveness toward other dogs and/or escape) was only observed in the placebo group, in 56 or 66% of the dogs as measured by respectively the veterinarian and the owners. Our study suggests that cyproterone acetate is effective and safe to supress the deslorelin induced behavioral flare-up effect, but not the rise in testosterone.

Correlation between age, testosterone and adiponectin concentrations, and sperm abnormalities in Simmental bulls

Background and Aim: Capacity for sperm production is affected by age, which is related to the morphology of sperm abnormalities and can affect fertility. The aim of this study was to evaluate the relationship between age and concentrations of testosterone and adiponectin with sperm abnormalities in Simmental bulls. Materials and Methods: The study used 11 bulls, separated into three groups. The first group consisted of five bulls aged 4-5 years, and the second and third groups each consisted of three bulls, aged 6-7 and 8-10 years, respectively. The average sperm motility of the animals ranged from 57.66±2.60% to 70.17±0.22%. Blood samples were obtained from the coccygeal region of the animals. Testosterone and adiponectin analysis was performed using the enzyme-linked immunosorbent assay method. Sperm morphology was evaluated using carbol fuchsin-eosin staining according to the Williams method. Finally, correlations between testosterone and adiponectin concentrations, age, and sperm abnormalities were analyzed using Pearson's correlation analysis. Results: The findings revealed a significant correlation (p<0.01) between the concentrations of testosterone and adiponectin (–0.538), age (–0.588), and abnormal sperm morphology (–0.912). Moreover, they revealed that the concentration of testosterone in the bulls aged 8-10 years was lower, at 21.89±4.56 ng/mL, compared to that in the bulls aged 4-5 years, at 36.15±1.29 ng/mL, and 6-7 years, at 35.16±5.39 ng/mL. The findings also revealed a positive correlation between adiponectin concentration and age (0.529) and sperm abnormalities (0.506). The increase in testosterone concentration was inversely related to the adiponectin concentration (–0.538). Moreover, the mean amount of abnormal sperm increased with increasing age: 3.82±0.33% in the group aged 4-5 years, and 4.40±0.72% and 10.20±1.97% in the groups aged 6-7 years and 8-10 years, respectively. Conclusion: The study data indicate that there is a decrease in testosterone concentration, a high adiponectin concentration, and an increase in abnormal sperm with increasing age in bulls.

Effects of Different Types of Exercise Training on Fine Motor Skills and Testosterone Concentration in Adolescents: A Cluster Randomized Controlled Trial

We sought to compare the effect of two types of exercise training on fine motor skills and to establish their association with the salivary testosterone. Research participants, 135 adolescents (68 adolescent females; mean age = 12.76, SD = 0.85) were assigned into three groups: coordinative exercise (CE), cardiovascular exercise (CVE), and the control group (CON). Fine motor skills were assessed with a drawing trail test and salivary testosterone concentration was measured before and after 10 weeks of intervention. There were no significant changes in fine motor skills and testosterone concentration after either CE or CVE training. However, a significant positive correlation between post-test fine motor skills and post-test testosterone concentration was found after the CVE training. One type of exercise training cannot be singled out as more effective for fine motor skills and testosterone activity. Nevertheless, our results showed a relationship between fine motor skills and testosterone concentration after the CVE training. Thus, the type of exercise training is important in the exercise-induced testosterone effect on fine motor skills.

Maternal Age and Maternal Environment Affect Egg Composition, Yolk Testosterone, Offspring Growth and Behaviour in Laying Hens

Maternal effects have been reported to alter offspring phenotype in laying hens. In this study, we investigated the effects of maternal environment and maternal age on egg traits and offspring development and behaviour. For this, we ran two experiments. First (E1), commercial hybrid hens were reared either in aviary or barren brooding cages, then housed in aviary, conventional cages or furnished (enriched) cages, thus forming different maternal housing treatments. Hens from each treatment were inseminated at three ages, and measures of egg composition, yolk testosterone concentration and offspring’s development, anxiety and fearfulness were assessed. In experiment 2 (E2), maternal age effects on offspring's growth and behaviour were further investigated using fertile eggs from commercial breeder flocks at three ages. Results from E1 showed that maternal age affected the majority of measures including egg composition, yolk testosterone, offspring growth, anxiety and fearfulness. Maternal rearing and housing affected fewer measures but included egg characteristics, offspring weight and behaviour. Effects of maternal age were not replicated in E2, possibly due to higher tolerance to maternal effects in commercial breeders. Overall, our research confirms that maternal environment and maternal age affect the offspring of laying hens in a variety of ways. These effects may be mediated by the natural decrease in egg yolk testosterone concentration over time.

Effect of Folic Acid by injection and supplementary on growth and puberty of Karadi male lambs

The present study is carried out to study the effect of Folic Acid (FA) by injection and supplementary on animal body weight gain, Testes volume before slaughtering, Testes volume after slaughtering, Testosterone concentration in blood, and FA concentration in blood. Twenty-five (25) Karadi male lambs five months aged and the average weight was 24.54 ±1.92 kg were used in this experiment. The animals weighed after three months of treatment to get animal increased live weight, The testes measured after one, two, and three months of treatment to calculate testes volume, testosterone, and FA concentration level in the blood were taken after one, two, and three months of treatment. The present study demonstrated that animal body weight, animal body weight gain, and total body weight gain significantly not increased (p>0.05). Testicular length, and testicular circumference not increased (p>0.05) after 1st, 2nd, and 3rd months after treatment, and after slaughtering. However, testicular high increased (p<0.05) after each month of treatment and slaughtering. Testosterone concentration in the blood significantly not different (p>0.05) reported between treatments after the 1st, 2nd, and 3rd months of treatment. FA concentration in the blood significantly increased (p<0.05) when used 3 and 6 mg FA by injection compared to control after 1st and 2nd months of treatment. However, blood FA concentration increased (p<0.05) when used FA 6mg/ml as an injection after the 2nd month of treatment compared to control. While using FA by supplementation and injection significantly (p>0.05) on the diameter and circumference of seminiferous tubules, germ cells thickness, and lumen diameters.

EFECT OF INTENSIVE PHYSICAL LOADS ON TESTOSTERONE, CORTISOL AND INSULIN BLOOD CONCENTRATIONS IN ELITE ATHLETES

The aim of the work was to investigate the effect of intense physical activity on testosterone, cortisol and insulin blood concentration in elite athletes. The study was conducted with the participation of 26 elite athletes of endurance events. This study assessed the resting hormones concentration before exercise and acute response of hormones concentration after intensive physical loads. The influence of intensive physical loads with different direction (strength and speed vs incremental load to VO2 max achievement) was investigated. The average values of total testosterone in blood serum, measured at rest state before exercise were 28,2 nmol·l-1, 40 minutes after exercise – 19,2 nmol·l-1. The mean concentration of cortisol was 506,2 nmol·l-1, after physical activity – 518,1 nmol·l-1. The average value morning insulin concentration was 6,6 μIU·l-1, after loading 5,6 μIU·l-1. It was established a significant (p = 0.001) decrease of the total testosterone concentration after intensive physical loads; the registered changes in the blood cortisol and insulin concentrations were not statistically significant. A significant correlation was established (p ≤ 0.05) between the maximum oxygen consumption (VO2max, ml·min·kg-1) and testosterone concentration (r = 0.76 resting morning concentration, r = 0.87 after intensive physical loads), cortisol (r = 0.69) and insulin (r = 0.51) after exercising. It was established the differences in testosterone concentration due intensive physical loads with various direction (strength and speed vs incremental load to VO2 max achievement). The significant difference of cortisol and insulin concentration depending the physical test was not found in this study.