Acute amino acids supplementation enhances pituitary responsiveness in athletes

Clinical Concerns on Sex Steroids Variability in Cisgender and Transgender Women Athletes

In the female athletic community, there are several endogenous and exogenous variables that influence the status of the hypothalamus-pituitary-ovarian axis and serum sex steroid hormones concentrations (e. g., 17β-estradiol, progesterone, androgens) and their effects. Moreover, female athletes with different sex chromosome abnormalities exist (e. g., 46XX, 46XY, and mosaicism). Due to the high variability of sex steroid hormones serum concentrations and responsiveness, female athletes may have different intra- and inter-individual biological and functional characteristics, health conditions, and sports-related health risks that can influence sports performance and eligibility. Consequently, biological, functional, and/or sex steroid differences may exist in the same and in between 46XX female athletes (e. g., ovarian rhythms, treated or untreated hypogonadism and hyperandrogenism), between 46XX and 46XY female athletes (e. g., treated or untreated hyperandrogenism/disorders of sexual differentiation), and between transgender women and eugonadal cisgender athletes. From a healthcare perspective, dedicated physicians need awareness, knowledge, and an understanding of sex steroid hormones' variability and related health concerns in female athletes to support physiologically healthy, safe, fair, and inclusive sports participation. In this narrative overview, we focus on the main clinical relationships between hypothalamus-pituitary-ovarian axis function, endogenous sex steroids and health status, health risks, and sports performance in the heterogeneous female athletic community.

Vitamin D, sport and health: a still unresolved clinical issue

Vitamin D metabolites have a pleiotropic role in human physiology, both in static and dynamic conditions, and a lot of vitamin D-related biological effects could influence physical and sport performances in athletes. Probably due to different factors (e.g., drugs, doping, nutrition, ultraviolet B radiation exposure), in athletes a very high prevalence of vitamin D inadequacy (i.e., deficiency or insufficiency) has been observed. Vitamin D inadequacy in athletes could be associated with specific health risks and to alterations of functional capacities, potentially influencing the fine adjustment of physical performances during training and sport competitions. When risk factors for vitamin D inadequacy exist, a preventive vitamin D supplementation is indicated, and if a vitamin D inadequacy is diagnosed, its supplementation is recommended. Unfortunately, on these issues many concerns remain unresolved. Indeed, it is not clear if athletes should be classified as a special population at increased risk for vitamin D inadequacy; moreover, in comparison to the non-athletic population, it is still not clear if athletes should have different reference ranges and different optimal target levels for serum vitamin D, if they have additional health risks, and if they need different type of supplementations (doses) for prevention and/or replacement therapy. Moreover, in athletes also the abuse of vitamin D supplements for ergogenic purposes raise different ethical and safety concerns. In this review, the main physio-pathological, functional and clinical issues that relate vitamin D to the world of athletes are described.

The use of prohibited substances for therapeutic reasons in athletes affected by endocrine diseases and disorders: the therapeutic use exemption (TUE) in clinical endocrinology

To protect sporting ethics and athletes' health, the World Anti-Doping Agency (WADA) produced the World Anti-Doping Code and The Prohibited List of substances and methods forbidden in sports. In accordance with the International Standards for Therapeutic Use Exemption (ISTUE), to avoid rule violations and sanctions, athletes affected by different endocrine diseases and disorders (e.g., adrenal insufficiency, diabetes, male hypogonadisms, pituitary deficit, thyroid diseases, etc.) who need to use a prohibited substance for therapeutic reasons (e.g., medical treatments, surgical procedures, clinical diagnostic investigations) must apply to their respective Anti-Doping Organizations (ADOs) to obtain a Therapeutic Use Exemption (TUE), if specific criteria are respected. The physicians who treat these athletes (i.e., endocrinologists, andrologists and diabetologists) are highly involved in these procedures and should be aware of their specific role and responsibility in applying for a TUE, and in adequately monitoring unhealthy athletes treated with prohibited substances. In this paper, the prohibited substances commonly used for therapeutic reasons in endocrine diseases and disorders (e.g., corticotropins, beta-blockers, glucocorticoids, hCG, insulin, GnRH, rhGH, testosterone, etc.), the role of physicians in the TUE application process and the general criteria used by ADO-Therapeutic Use Exemption Committees (TUECs) for granting a TUE are described.

Sport, doping and male fertility

It is universally accepted that lifestyle interventions are the first step towards a good overall, reproductive and sexual health. Cessation of unhealthy habits, such as tobacco, alcohol and drug use, poor nutrition and sedentary behavior, is suggested in order to preserve/improve fertility in humans. However, the possible risks of physical exercise per se or sports on male fertility are less known. Being "fit" does not only improve the sense of well-being, but also has beneficial effects on general health: in fact physical exercise is by all means a low-cost, high-efficacy method for preventing or treating several conditions, ranging from purely physical (diabetes and obesity) to psychological (depression and anxiety), highly influencing male reproduction. If male sexual and reproductive health could be positively affected by a proper physical activity, inadequate bouts of strength - both excessive intensity and duration of exercise training - are more likely to have detrimental effects. In addition, the illicit use of prohibited drugs (i.e. doping) has reached pandemic proportions, and their actions, unfortunately very often underestimated by both amateur and professional athletes, are known to disrupt at different levels and throughout various mechanisms the male hypothalamic-pituitary-gonadal axis, resulting in hypogonadism and infertility.

Sport and male sexuality

The relationships between sport and sexuality in males are of great social and clinical interest, because of sports and motor activities that highly promote social and sexual relationships. Even if few literature exist, two main questions should be taken into account: whether and how physical exercise and sport positively or negatively influence sexual health and behavior and/or whether and how sexual behavior may affect a sub-sequent sport performance. Physical exercise and sport per se can influence, positively or negatively, the hypothalamic-pituitary-testicular axis function and, consequently, the individual's reproductive and/or sexual health. This depends on individual factors such as genetic and epigenetic ones and on different variables involved in the practice of sport activities (type of sport, intensity and duration of training, doping and drug use and abuse, nutrition, supplements, psychological stress, allostatic load, etc.). If well conducted, motor and sport activities could have beneficial effects on sexual health in males. Among different lifestyle changes, influencing sexual health, regular physical activity is fundamental to antagonize the onset of erectile dysfunction (ED). However, competitive sport can lead both reproductive and/or sexual tract damages and dysfunctions, transient (genital pain, hypoesthesia of the genitalia, hypogonadism, DE, altered sexual drive, etc.) or permanent (hypogonadism, DE, etc.), by acting directly (traumas of the external genitalia, saddle-related disorders in cyclists, etc.) or indirectly (exercise-related hypogonadism, drug abuse, doping, stress, etc.). Sexual activities shortly performed before a sport competition could differently influence sport performance. Due to the few existing data, it is advisable to avoid an absolute pre-competition sexual abstinence.

Effect of taking dietary supplement on hematological and biochemical parameters in male bodybuilders an equation model

Background:

The improved physical action following administration of supplements to bodybuilders was supported by changes in laboratory parameters. Despite the fact that these supplements are sometimes associated both advantage and side effects, this study were conducted for the purpose of evaluating the possible effects of some commonly used supplements in bodybuilders on the hematological and biochemical parameters.

Materials and Methods:

In this study, we included 40 male bodybuilders as cases and 40 controls in the age group of 20-40 years. They used different kinds of supplements for 1 year. In general, all the supplements used were classified into two groups: hormonal and non-hormonal. Laboratory tests were requested for evaluation of hematological and biochemical parameters.

Results:

In an equation model, we found that weight (P = 0.024), duration of bodybuilding (P < 0.001), and duration of hormone supplement consumption (P < 0.001) were loaded significantly on the latent variables, demographic and dietary supplement, respectively. The relationship between dietary supplement and biochemical and hematological parameters was significant (P = 0.01) and some of these parameters including creatinine (P = 0.023), blood aspartate aminotransferase (AST) (P < 0.001), alanine aminotransferase (ALT) (P < 0.001), and red blood cell distribution (RDW) (P = 0.046) had a significant role than others. In a multivariate regression model, we found that WBC (P < 0.001), platelets (P < 0.001), blood urea nitrogen (BUN; P < 0.001), creatinine (P < 0.001), AST (P = 0.005), and ALT (P = 0.001) were higher in athletes than in controls.

Conclusions:

It is strongly advised that there should be some concerns about possible supplement-induced changes in the laboratory exams for bodybuilders. The available supplements are unchecked and not approved by the US Food and Drug Administration (FDA). More studies should be designed for a better and precise administration of each supplement in athletes.

Testosterone responses to standardized short-term sub-maximal and maximal endurance exercises: issues on the dynamic adaptive role of the hypothalamic-pituitary-testicular axis

BACKGROUND

Few and conflicting data on the acute adaptive role of the hypothalamic-pituitary-testicular (HPT) axis to sub-maximal endurance exercise exist.

AIMS

To investigate the acute HPT axis responses to standardized endurance exercises in a laboratory setting and the correlations between testosterone and classic adaptive hormones variations.

SUBJECTS AND METHODS

12 healthy male volunteers were recruited for this experimental study. Serum PRL, GH, ACTH, LH, cortisol, DHEAS, testosterone [total (TT), calculated free (cFT) and bioavailable (cBioT)], SHBG, and respective ratios, were evaluated before and after a 30-min sub-maximal exercise on cycle ergometer at individual anaerobic threshold (IAT) and a maximal exercise until exhaustion. Blood samples were collected before exercise (30, 15 min and immediately before), immediately after and at different time points during recovery (+15, +30 and +60 min) for hormones assays. Oxygen consumption and lactate concentration were evaluated.

RESULTS

Testosterone (TT, cFT and cBioT) acutely increased in all volunteers after both exercises. Testosterone increased in parallel to GH after both exercises and to cortisol only after maximal exercise. Differently from other increased hormones, testosterone increases were not correlated to exercise-intensity-related variables. The anabolic/catabolic steroids ratios were higher after sub-maximal exercise, compared to maximal.

CONCLUSIONS

A 30-min sub-maximal endurance exercise acutely increased serum testosterone similarly to maximal exercise, but without cortisol increases. Exercise-related testosterone peaks should be considered adaptive phenomena, but few data on their short- and long-term effects exist. Investigations on the mechanisms of adaptation to exercise in active individuals with physiological or pathological hypo-testosteronemia are warranted.

Toxic hepatitis in a group of 20 male body-builders taking dietary supplements

Dietary supplements have been used for decades for enhancing muscle growth. The harm caused by some of these products is well documented. We investigated and reported toxic hepatitis in 20 male athletes following self-prescribing of a number of dietary supplements which are lesser known. The patients' ages ranged from 24 to 32 with a mean of 28 years. They had taken three kinds of supplements for 1 year including testosterone optimizer agent T Bomb II, a creatine supplement Phosphagen and an amino acid based supplement Cell-Tech. Based on the history, clinical examination, and laboratory findings the cases were diagnosed as toxic hepatitis. After discontinuation of taking the supplements, clinical recovery and improvement of liver function tests were achieved within 30 days. Causality assessment with the CIOMS (Council for International Organization Medical Sciences) scale showed a "possible" grade of causality (+5 points) for these supplements. It can be concluded that these newer anabolic supplements may induce toxic hepatitis. Since the health risks of them may be severe, the use of these kinds of dietary supplements should be discouraged.

Concerns about serum androgens monitoring during testosterone replacement treatments in hypogonadal male athletes: a pilot study

INTRODUCTION

A well-tailored testosterone replacement treatment (TRT) in male hypogonadal athletes plays a pivotal role to restore physiological performances, to reduce health risks, and to guarantee the ethic of competition. Few studies evaluated individual androgens profiles during TRT in trained individuals.

AIM

The aim of this article was to verify the efficacy in restoring eugonadal serum and urinary androgens profiles after testosterone enanthate (TE) and gel (TG) administration.

METHODS

Ten male Caucasian-trained volunteers affected by severe hypotestosteronemia (<8 nmol/L) were included. Serum androgens and urinary testosterone metabolites were evaluated, in the same subjects, before and weekly for 5 weeks after both a single intramuscular TE injection (250 mg) and during a daily administration of TG (50 mg/die of testosterone), respectively.

MAIN OUTCOME MEASURES

The main outcome measures of this article were serum total testosterone (TT), dihydrotestosterone (DHT), calculated free and bioavailable testosterone (cFT, cBioT), 17-β-estradiol, and urinary glucuronide testosterone metabolites.

RESULTS

Supraphysiological TT concentrations were observed in 50% of our volunteers until 7 days after TE and in the 4% of total samples after TG. Serum DHT was high both after TE (all volunteers on day 7 and 50% on day 14) and during TG (32% of total samples). A relatively low number of samples showed normal cFT and cBioT both after TE and TG (20-44%, respectively). Urinary metabolites were related to the type of treatment and to serum androgens profile and resulted in the normal ranges from 15% to 60% of total samples.

CONCLUSION

Besides well-known variations of mean serum TT, we showed a high percentage of serum and urinary samples with abnormal androgens, being TG safer than TE. We conclude that monitoring TRT with TT only may be inaccurate because of abnormal fluctuations of other circulating androgens. Further studies to identify the appropriate markers of eugonadism during TRT are highly warranted both in athletes and in non-athletes.

A blend of chlorophytum borivilianum and velvet bean increases serum growth hormone in exercise-trained men

Background:

Several isolated ingredients have been proposed to increase growth hormone (GH) release, including Chlorophytum borivilianum and Velvet bean. A combination of these two ingredients has been packaged within an investigational dietary supplement. It was the purpose of the present investigation to determine the impact of acute ingestion of this supplement on circulating GH in healthy, exercise-trained men.

Methods:

Fifteen men ingested the dietary supplement on two different days, separated by one week. Blood was collected from subjects before ingestion of the supplement and at 20, 40, 60, 80, 100, and 120 minutes post ingestion. GH was analyzed in serum samples using an ELISA method. Values for GH for each subject, at each collection time, were averaged over both test days and used in the main analysis.

Results:

Serum GH increased over time, with higher values at 60 minutes (1.56 ± 0.65 ng · mL⁻¹; P = 0.04; +767%), 80 minutes (1.76 ± 0.69 ng · mL⁻¹; P = 0.02; +878%), and 100 minutes (1.48 ± 0.62 ng · mL⁻¹; P = 0.05; +722%) compared to pre ingestion (0.18 ± 0.04 ng · mL⁻¹). A great deal of subject variability existed in the area under the curve (AUC) for GH, with pooled values ranging from 0.49 to 61.2 ng · mL⁻¹ · 2 hr⁻¹

Conclusion:

Acute ingestion of an investigational dietary supplement containing the active ingredients Chlorophytum borivilianum and Velvet bean results in an increase in circulating GH in exercise-trained men. Additional placebo controlled investigations are needed to extend these findings. Moreover, studies are needed to determine if chronic use of such supplementation leads to favorable changes in health-related parameters associated with increased circulating GH.

Urinary and serum hormones profiles after testosterone enanthate administration in male hypogonadism: concerns on the detection of doping with testosterone in treated hypogonadal athletes

OBJECTIVE

To describe serum and urinary hormones, androgens metabolites and testosterone/epitestosterone ratio profiles after testosterone administration in male hypogonadal volunteers, and to evaluate their possible usefulness in detecting doping with testosterone in treated hypogonadal athletes.

DESIGN

Controlled open label design vs placebo; pharmacokinetic study.

PARTICIPANTS

Ten male volunteers affected by severe hypogonadism (serum testosterone <2.31 ng/ml).

INTERVENTIONS AND MAIN OUTCOME MEASURES

Serum and urinary parameters were evaluated, by radioimmunoassay and gas chromatography-mass spectrometry, before and at different time points for 7/3 weeks after a single administration of testosterone enanthate (250 mg) or placebo, respectively.

RESULTS

As partially known, testosterone administration increased, with great individual variability, urinary concentrations of glucuronide testosterone, androsterone, etiocholanolone, 5alpha-androstane- 3alpha,17beta-diol, 5beta-androstane-3alpha,17beta-diol, testosterone/ epitestosterone and testosterone/LH ratios; and decreased epitestosterone and 5alpha-androstane-3beta,17beta-diol/5beta-androstane- 3alpha,17beta-diol ratio. Serum testosterone and dihydrotestosterone increased in all volunteers, and concentrations higher than the upper reference limits were observed in many volunteers until 2 weeks after testosterone administration.

CONCLUSION

Whereas the observed prolonged hyperandrogenism partially limited data interpretation, the report ed characteristics of variation of urinary parameters might be used to suspect testosterone misuse in hypogonadal athletes treated with testosterone enanthate. In this sense, while the actual threshold for tes tos terone/epites tos ter one ratio was confirmed to be of reduced usefulness, we suggest a contemporary evaluation of whole urinary androgen metabolites profile and serum androgens, at specific time points after testosterone enanthate administration. Moreover, an adequate tailoring of treatment, to avoid transitory hyperandrogenism, is highly advisable. Further studies on strategies for detecting doping with testosterone in hypogonadal athletes are warranted.

Supplements and the endocrine system in athletes

In the world of athletes' nutrition, there are many ethical concerns, because there is the suspicion that in practice, large doses of supplements in athletes are not taken for nutritional purposes. It is beyond the scope of this article to highlight the possible roles of supplements or methods of supplementation in the improvement of athletic performance in elite athletes. Instead, the author briefly reviews some of the substances taken by athletes, with particular attention to their mechanisms of action and the pathways involved. Very often, the effects of many supplements are hormone-related, or supplements influence hormone secretion. Examples of possible links between "supplements or ergogenic compounds" and the endocrine/metabolic system are addressed.

Cortisol, dehydroepiandrosterone sulphate and dehydroepiandrosterone sulphate/cortisol ratio responses to physical stress in males are influenced by pubertal development

To evaluate the influence of chronological age and pubertal development on the hypothalamus-pituitary-adrenal (HPA) axis response to stress, we studied the possible correlations between male pubertal characteristics and salivary cortisol (C), DHEAS and the DHEAS/C ratio before (pre-stress) and after acute exercise-stress in young male volunteers (no. 87; 13.3+/-2.1 yr). In our overall study population, the mean pre-stress salivary C and DHEAS concentrations, significantly increased after exercise-related stress, whereas the DHEAS/C ratio significantly decreased. Pre-stress salivary C was positively correlated with chronological age, and after-stress salivary C concentration variations were negatively correlated with pubertal stage, mean testis volume and pre-stress salivary DHEAS. Furthermore, salivary DHEAS concentrations and the DHEAS/C ratio, before and after exercise stress, were positively correlated with chronological age, pubertal stage, pre-stress salivary testosterone (T), testis volume and body mass index (BMI). In contrast with late pubertal stages (P4, P5), young individuals at early stages of puberty (P1 to P3) showed higher C increase and lower DHEAS/C ratio after exercise-related stress. In conclusion, since C is also a mediator of stress-related negative effects on health and the DHEAS/C ratio has been hypothesized as an index for the degree to which an individual is buffered against the negative effects of stress, these data might suggest potentially increased stress-related risks at early stages of male puberty.

Research of stimulants and anabolic steroids in dietary supplements

The purpose of this study was to analyze the composition of 103 dietary supplements bought on the internet. The supplements were dispatched in four different categories according to their announced contents [creatine, prohormones, "mental enhancers" and branched chain amino acids (BCAA)]. All the supplements were screened for the presence of stimulants and main anabolic steroids parent compounds. At the same time, the research was focused on the precursors and metabolites of testosterone and nandrolone. The study pointed out three products containing an anabolic steroid, metandienone, in a very high amount. The ingestion of such products induced a high quantity of metandienone metabolites in urines that would be considered as a positive antidoping test. The results have also shown that one creatine product and three "mental enhancers" contained traces of hormones or prohormones not claimed on the labels and 14 prohormone products contained substances other than those indicated by the manufacturer. The oral intake of the creatine product revealed the presence of the two main nandrolone metabolites (19-norandrosterone and 19-noretiocholanolone) in urine.

Anti-stress and Adaptogenic Activity of l-Arginine Supplementation

In the present study, oral supplementation of l-arginine in rats was evaluated for its anti-stress and adaptogenic activity using the cold (5 degrees C)-hypoxia (428 mmHg)-restraint (C-H-R) animal model. A dose-dependent study of l-arginine was carried out at doses of 12.5, 25.0, 50.0, 100.0, 200.0 and 500.0 mg/kg body weight, administered orally 30 min prior to C-H-R exposure. The time taken by the rat to attain a rectal temperature of 23 degrees C (T(rec) 23 degrees C) during C-H-R exposure and its recovery to T(rec) 37 degrees C at normal atmospheric pressure and 32 +/- 1 degrees C were used as biomarkers of anti-stress and adaptogenic activity. Biochemical parameters related to lipid peroxidation, anti-oxidants, cell membrane permeability, nitric oxide and stress, with and without administration of the least effective l-arginine dose, were measured in rats on attaining T(rec) 23 degrees C and T(rec) 37 degrees C. The least effective adaptogenic dose of l-arginine was 100.0 mg/kg body weight. The C-H-R exposure of control rats, on attaining T(rec) 23 degrees C, resulted in a significant increase in plasma malondialdehyde (MDA), blood lactate dehydrogenase (LDH) and a decrease in blood catalase (CAT) and plasma testosterone levels. On recovery (T(rec) 37 degrees C) of control rats, there was a further decrease in CAT and plasma testosterone, and an increase in LDH. l-Arginine supplementation resulted in a significant decrease in plasma MDA, an increase in blood superoxide dismutase (SOD), CAT levels maintained at control values and a lower increase in LDH compared with controls (45.3 versus 58.5% and 21.5 versus 105.2%) on attaining T(rec) 23 degrees C during C-H-R exposure and on recovery to T(rec) 37 degrees C. The results suggested that l-arginine possesses potent anti-stress activity during C-H-R exposure and recovery from C-H-R-induced hypothermia.

Nutritional supplements in Norwegian elite athletes--impact of international ranking and advisors

The aims of this study were to investigate (a) the use of nutritional supplements (NS) (vitamins, minerals, Omega 3, antioxidants, ginseng, amino acids, Creatine and energy supplements) in elite athletes of different international ranking (b) why athletes are using NS, and (c) who recommends the elite athletes to use NS. The total population of elite athletes in Norwegian National Teams (n = 1620, 960 males and 660 females aged 15-39 years) and randomly selected (n = 1681) (916 males and 765 females) controls from the general population, were given a questionnaire including questions about use of nutritional supplements (NS), and from whom athletes had received information about nutrition and recommendations to use NS. The response rate was 76% for male and 92% for female athletes and 75% and 81% for male and female controls, respectively. A similar percentage of female athletes (54%) and controls (52%) reported use of one or more NS, but more male athletes (51%) than male controls (32%) used NS (P < 0.001). However, independent of gender, more athletes as compared to controls used minerals (males 26% vs. 8%; females 42% vs. 20%), amino acids (males 12% vs. 4%; females 3% vs. 0), and Creatine (males 12% vs. 2%; females 3% vs. 0). A lower percentage of NS users were observed in the best female athletes (52%) as compared to female athletes with less experience of international competition (73%) (P < 0.01). In male athletes, NS use was independent of international ranking (49%-53%). The coach was the main advisor for use of NS for both male (58%) and female athletes (52%). For male and female athletes, the main reason for using NS was that they felt it was needed in addition to their daily intake (56% and 67%, respectively). Forty one percent of the male and 37% of the female athletes using NS felt they were well informed about nutrition in general and NS. However, 8% of the NS users did not know whether the NS they used was doping classified or not.

IN CONCLUSION

we found that a similar percentage of female elite athletes and controls, but a higher percentage of male elite athletes than controls, reported the use of NS. There was a lower percentage of NS use among the top female athletes, but not the top male athletes as compared to the less successful elite athletes. The coach was the main advisor for NS use both for male and female elite athletes.

IGF-I, IGFBP-2, and -3: do they have a role in detecting rhGH abuse in trained men?

PURPOSE

Although the illegal use of recombinant human growth hormone (rhGH) to enhance performance is increasing among athletes, no official test for its detection has yet been implemented. The aim of this work was to study how prolonged rhGH administration in trained subjects influences the insulin-like growth factor (IGF) system, in order to evaluate new methods in antidoping tests.

METHODS

Morning serum growth hormone (GH), IGF-I, IGF binding protein (BP)-2, IGFBP-3, IGF-I/IGFBP-2, and IGFBP-3/IGFBP-2 ratios were evaluated before, during (8th and 15th days), and at the end and after cessation (+3, +6, +9, +12, and +15 d) of a 3-wk treatment with different doses of rhGH (0.09 IU.kg BW(-1).d(-1) for 6 or 3 d a week, i.e., the A and B trials, respectively) in seven well-trained subjects not involved in competitive sports. The blood collections pre- and during treatment were performed immediately before the daily rhGH dose.

RESULTS

In both trials, significant increases of IGF-I (higher in the A trial) and IGFBP-3 serum concentrations during rhGH administration were observed. Serum IGFBP-3 remained significantly increased in the A trial 3 d after treatment cessation. In the A trial only, two subjects had IFG-I concentrations exceeding the upper limit of the reference range. No modifications of serum GH, IGFBP-2 and IGF-I/IGFBP-2, and IGFBP-3/IGFBP-2 ratios were observed. The z-score evaluation for IGFBP-3 detected GH exposure in 100% of subjects only at end treatment in A trial.

CONCLUSION

Although IGF-I and IGFBP-3 seem potentially the most specific markers of rhGH assumption, our data suggest that for antidoping purposes a single evaluation of their absolute serum concentration is not a sufficiently secure method to detect rhGH abuse in all subjects, especially in the case of low rhGH doses.

Acetylsalicylic acid inhibits the pituitary response to exercise-related stress in humans

PURPOSE

Prostaglandins (PGs) modulate the activity of the hypothalamus-pituitary axis, and pituitary hormones are largely involved in the physiological responses to exercise. The purpose of this study was to analyze the effects of acetylsalicylic acid (ASA), an inhibitor of PGs synthesis, in the pituitary responses to physical stress in humans.

METHODS

Adrenocorticotropin (ACTH), beta-endorphin, cortisol, growth hormone (GH), and prolactin (PRL) responses to exercise were evaluated after administration of either placebo or ASA. Blood samples for hormone evaluations before (-30, -15, and 0 pre) and after (0 post, +15, +30, +45, +60, and +90 min) a 30-min treadmill exercise (75% of .VO(2max)) were taken from 12 male athletes during two exercise trials. One tablet of ASA (800 mg), or placebo, was administered two times daily for 3 d before and on the morning of each exercise-test.

RESULTS

The results clearly show that, compared with placebo, ASA ingestion significantly blunted the increased serum ACTH, beta-endorphin, cortisol, and GH levels before exercise (anticipatory response) and was associated with reduced cortisol concentrations after exercise. Furthermore, although no differences in the GH response to exercise were shown, a significantly reduced total PRL response to stress condition was observed after ASA.

CONCLUSION

ASA influences ACTH, beta-endorphin, cortisol, GH, and PRL responses to exercise-related stress in humans (preexercise activation/exercise-linked response). Even though it is not possible to exclude direct action for ASA, our data indirectly confirm a role of PGs in these responses. We have to further evaluate the nature of the preexercise endocrine activation and, because of the large use of anti-inflammatory drugs in athletes, whether the interaction between ASA and hormones might positively or negatively influence health status, performance, and/or recovery.

Lysine: Is it worth more?

Lysine, an essential cationic amino acid, has a positively charged R group. The structure of lysine is given as (H(3)N(+)-)CH(-COO(-))-CH(2)-CH(2)-CH(2)-CH(2)-N(+)H(3).While the anabolic role(s) of the molecule has been in focus for quite a few decades now, its biological properties, e.g. role in cellular proliferation in vitro (both anchorage dependent and anchorage independent) and in vivo, its ability to induce strong inflammatory and immune responses - both humoral and cell mediated, its role in augmented healing of all types of wounds in animal models as well as in human subjects (both acute and chronic), as well as its role in inducing extensive angiogenic responses, have never received reasonable attention so far. In the current brief and indicative review (rather than exhaustive reviews of each area), we intend to bring these biological properties of the molecule to focus while discussing a few other interesting aspects - lysine as a food preservative as well as its possible role(s) in immune therapy. While the areas look extremely divergent, we propose a common denominator in the form of a possible molecular mechanism of action of the molecule in all these diverse situations.

High-intensity dynamic human muscle performance enhanced by a metabolic intervention

PURPOSE

The purpose of this study was to quantify the effects of a metabolic treatment on human muscle dynamic performance (strength, work, and fatigue) measured under conditions of acute, exhaustive high-intensity anaerobic isokinetic exercise.

METHODS

Unilateral prefatigue and postfatigue peak torque and work values were measured in the quadriceps femoris of 13 subjects using a computer-controlled isokinetic dynamometer, over a 23-d interval. The two experimental treatments were: 1) a glycine and L-arginine salt of alpha-ketoisocaproic acid calcium ("GAKIC"); and 2) isocaloric sucrose (control). Based on a randomized double-blind cross-over repeated measures design, measurements were made before and during an exhaustive anaerobic fatigue protocol to calculate a Fatigue Resistance Index (FRI = [peri-exhaustion torque]\[baseline peak torque]), as well as total work.

RESULTS

The FRI and total work for each of the exhaustion sets measured at 0, 5, and 15 min after oral GAKIC treatment were greater than values obtained for isocaloric control treatment (P < 0.02). GAKIC treatment increased the mean resistance to fatigue (FRI) up to 28% over isocaloric control. Overall gain in total muscle work attributable to GAKIC was 10.5 +/- 0.8% greater than control, sustained for at least 15 min. After 24 h, both GAKIC and control concentric forces returned to the same absolute values (P > 0.05): mean FRI = 0.42 +/- 0.05 and mean total work = 4600 +/- 280 J. There were no significant differences attributable to random order of testing.

CONCLUSIONS

Compared with isocaloric carbohydrate, oral GAKIC treatment increased muscle torque and work sustained during intense acute anaerobic dynamic exercise; additionally, it increased overall muscle performance by delaying muscle fatigue during the early phases of anaerobic dynamic exercise.