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The efficacy of ergogenic agents in athletic competition. Part I: Androgenic-anabolic steroids.

OBJECTIVE: To summarize the literature describing the epidemiology, pharmacology, efficacy, and adverse effects associated with androgenic-anabolic steroid (AAS) use among athletes. DATA SOURCES: Relevant articles were identified from a MEDLINE search using the search terms "Doping in Sports," "Anabolic Steroids (exploded)," and "Androgens (exploded)." Additional references were found in the bibliographies of these articles. STUDY SELECTION/DATA EXTRACTION: We reviewed studies of AAS use among professional athletes. Interpretation of these studies is difficult because of poor research design. The efficacy studies lacked adequate placebo control. Much of the literature describing adverse effects consists of anecdotal reports. All of this literature was considered for review. DATA SYNTHESIS: Of all ergogenic drugs, AASs are the most widely abused. Abuse of AASs among high school students is estimated at five to ten percent. AASs are hypothesized to produce ergogenic effects during periods of concomitant positive nitrogen balance via antagonism of the catabolic effect of glucocorticoids released during intense exercise. Despite years of study, the extent of the ergogenic effects associated with AASs remains unclear. This may be because most studies have failed to approximate athletes' AAS usage patterns. The primary toxic effects of AASs are divided into four areas: hepatic, reproductive, cardiovascular, and psychiatric. Athletes do not consider these effects severe enough to refrain from using these drugs. CONCLUSIONS: Athletes view AASs as an essential component for success. Without adequate intervention measures, AAS abuse is likely to continue unchecked.

Anabolic Agents↗

Incidence of reported cerebral concussion in adult taekwondo athletes.

The purpose of the present study was to assess the exact conditions under which cerebral concussions occur in full-contact taekwondo competition. Injury data were collected by project staff and tournament medical personnel with simple check-off forms that describe the athlete and nature, site, circumstances and severity of the injury. The Mann-Whitney U test was used to determine the difference in injury rate between men and women. The men (7.04/1,000 athlete-exposures) sustained more cerebral concussions than the women (2.42/1,000 athlete-exposures) (p < 0.001). The dominant injury mechanism in both the males and females was receiving a blow (6.46/1,000 athlete-exposures and 2.42/1,000 athlete-exposures for the men and women, respectively).

Adult↗

Assessment of QT interval duration and dispersion in athlete's heart.

An athlete's heart is characterized by morphological and functional changes occurring as a consequence of regular physical exercise. We sought to determine if these physiological changes lead to ventricular repolarization abnormalities in trained athletes. Forty-four trained athletes and 35 sex- and age-matched healthy sedentary controls were included in the study. A 12-lead surface electrocardiogram (ECG) was obtained from all participants. Maximum QT (QTmax) and minimum QT (QTmin) interval durations, QT dispersion (QTd) and corrected QT dispersion (QTcd) were calculated for each ECG record. Heart rate, systolic and diastolic blood pressure values were found to be identical in both groups. QTmax and QTmin interval durations were not statistically different between the athletic and control groups. Similarly, QTd and QTcd did not differ significantly between the two groups. No association was observed between an athlete's heart and ventricular heterogeneity compared with healthy sedentary controls, despite physiological and structural changes.

Adult↗

Comparison of platelet function between sedentary individuals and competitive athletes at rest.

BACKGROUND: There are controversial evidences on the effect of different types and workloads of physical exercise on primary hemostasis. In particular, little is known on the chronic influence of a strenuous and regular aerobic training regimen on platelet function. METHODS: The aim of this investigation was to compare platelet function between sedentary controls and trained athletes at rest and to evaluate whether a greater amount of exercise performed in professional cyclists may contribute to increased platelet chronic responsiveness compared to both elite cyclists and sedentary individuals. Platelet's ability to adhere and aggregate was assayed following a 12-24 h resting period in 49 active professional male road cyclists, 40 elite male cyclists and 43 matched sedentary healthy male volunteers, by the platelet function analyzer 100 (PFA-100). RESULTS AND DISCUSSION: Mean values of the collagen-epinephrine test did not differ between controls and athletes (sedentary controls: 111 +/- 33 s; elite athletes: 113 +/- 26 s, p = 0.93; professional athletes: 120 +/- 33 s; p = 0.33), whereas mean values of the collagen-ADP test displayed a slightly but significant trend towards decreased values when comparing sedentary controls (83 +/- 21 s) with either elite (77 +/- 11 s, p < 0.01) or professional (75 +/- 16 s, p < 0.01) athletes. CONCLUSION: The trend towards slightly lower collagen-ADP values are suggestive for a modest but significant chronic activation of primary hemostasis, highlighting the need to set appropriate reference ranges for the PFA-100 when evaluating primary hemostasis in physically active subjects.

Journal Article↗

Blood doping by cobalt. Should we measure cobalt in athletes?

BACKGROUND: Blood doping is commonplace in competitive athletes who seek to enhance their aerobic performances through illicit techniques. PRESENTATION OF THE HYPOTHESIS: Cobalt, a naturally-occurring element with properties similar to those of iron and nickel, induces a marked and stable polycythemic response through a more efficient transcription of the erythropoietin gene. TESTING THE HYPOTHESIS: Although little information is available so far on cobalt metabolism, reference value ranges or supplementation in athletes, there is emerging evidence that cobalt is used as a supplement and increased serum concentrations are occasionally observed in athletes. Therefore, given the athlete's connatural inclination to experiment with innovative, unfair and potentially unhealthy doping techniques, cobalt administration might soon become the most suited complement or surrogate for erythropoiesis-stimulating substances. Nevertheless, cobalt administration is not free from unsafe consequences, which involve toxic effects on heart, liver, kidney, thyroid and cancer promotion. IMPLICATIONS OF THE HYPOTHESIS: Cobalt is easily purchasable, inexpensive and not currently comprehended within the World Anti-Doping Agency prohibited list. Moreover, available techniques for measuring whole blood, serum, plasma or urinary cobalt involve analytic approaches which are currently not practical for antidoping laboratories. Thus more research on cobalt metabolism in athletes is compelling, along with implementation of effective strategies to unmask this potentially deleterious doping practice.

Journal Article↗

The importance of early arthroscopy in athletes with painful cartilage lesions of the ankle: a prospective study of 61 consecutive cases.

BACKGROUND: Ankle sprains are common in sports and can sometimes result in a persistent pain condition. PURPOSE: Primarily to evaluate clinical symptoms, signs, diagnostics and outcomes of surgery for symptomatic chondral injuries of the talo crural joint in athletes. Secondly, in applicable cases, to evaluate the accuracy of MRI in detecting these injuries. TYPE OF STUDY: Prospective consecutive series. METHODS: Over around 4 years we studied 61 consecutive athletes with symptomatic chondral lesions to the talocrural joint causing persistent exertion ankle pain. RESULTS: 43% were professional full time athletes and 67% were semi-professional, elite or amateur athletes, main sports being soccer (49%) and rugby (14%). The main subjective complaint was exertion ankle pain (93%). Effusion (75%) and joint line tenderness on palpation (92%) were the most common clinical findings. The duration from injury to arthroscopy for 58/61 cases was 7 months (5.7-7.9). 3/61 cases were referred within 3 weeks from injury. There were in total 75 cartilage lesions. Of these, 52 were located on the Talus dome, 17 on the medial malleolus and 6 on the Tibia plafond. Of the Talus dome injuries 18 were anteromedial, 14 anterolateral, 9 posteromedial, 3 posterolateral and 8 affecting mid talus. 50% were grade 4 lesions, 13.3% grade 3, 16.7% grade 2 and 20% grade 1. MRI had been performed pre operatively in 26/61 (39%) and 59% of these had been interpreted as normal. Detection rate of cartilage lesions was only 19%, but subchondral oedema was present in 55%. At clinical follow up average 24 months after surgery (10-48 months), 73% were playing at pre-injury level. The average return to that level of sports after surgery was 16 weeks (3-32 weeks). However 43% still suffered minor symptoms. CONCLUSION: Arthroscopy should be considered early when an athlete presents with exertion ankle pain, effusion and joint line tenderness on palpation after a previous sprain. Conventional MRI is not reliable for detecting isolated cartilage lesions, but the presence of subchondral oedema should raise such suspicion.

Journal Article↗

Role of psychological stress in cortisol recovery from exhaustive exercise among elite athletes.

Life-event stress (LES) was used to classify elite athletes (n = 39) into high- and low-LES groups. A repeated measures analysis of variance revealed higher cortisol concentration after a graded exercise lest among the high-LES group relative to the low-LES group, which was maintained for up to 20 hr. Subsequent prospective analyses further indicated that high-LES athletes were more likely lo he symptomatic than low-LES athletes and that elevated cortisol level was positively correlated with symptomatology. To the extent that cortisol is a marker of exercise recovery in competitive athletes. our results suggest that chronic stress prolongs the recovery process, which may potentially widen a window of susceptibility for illness and injury among competitive athletes.

Journal Article↗

Effects of high-dose growth hormone on glucose and glycerol metabolism at rest and during exercise in endurance-trained athletes.

CONTEXT: Recombinant human-GH (r-hGH), in supraphysiological doses, is self-administered by athletes in the belief that it is performance enhancing. OBJECTIVE: The objective of this study was to determine whether r-hGH alters whole-body glucose and glycerol metabolism in endurance-trained athletes at rest and during and after exercise. DESIGN: This was a 4-wk double-blind placebo-controlled trial. SETTING: This study was conducted at St. Thomas Hospital (London, UK). PARTICIPANTS: Twelve endurance-trained male athletes were recruited and randomized to r-hGH (0.2 U/kg.d) (n = 6) or identical placebo (n = 6) for 4 wk. One (placebo group) withdrew after randomization. INTERVENTION: Intervention was conducted by randomization to r-hGH (0.2 U/kg x d) or identical placebo for 4 wk. MAIN OUTCOME MEASURES: Whole-body rates of appearance (Ra) of glucose and glycerol (an index of lipolysis) and rate of disappearance of glucose were measured using infusions of d-[6-6-2H2]glucose and 2H5-glycerol. RESULTS: Plasma levels of glycerol and free fatty acids and glycerol Ra at rest and during and after exercise increased during r-hGH treatment (P < 0.05 vs. placebo). Glucose Ra and glucose rate of disappearance were greater after exercise during r-hGH treatment (P < 0.05 vs. placebo). Resting energy expenditure and fat oxidation were greater under resting conditions during r-hGH treatment (P < 0.05 vs. placebo). CONCLUSIONS: r-hGH in endurance-trained athletes increased lipolysis and fatty acid availability at rest and during and after exercise. r-hGH increased glucose production and uptake rates after exercise. The relevance of these effects for athletic performance is not known.

Adult↗

Elevated plasma low-density lipoprotein and high-density lipoprotein cholesterol levels in amenorrheic athletes: effects of endogenous hormone status and nutrient intake.

To determine the interactive effects of hormones, exercise, and diet on plasma lipids and lipoproteins, serum estrogen and progesterone levels, nutrient intake, and plasma lipid, lipoprotein, and apolipoprotein concentrations were measured in 24 hypoestrogenic amenorrheic and 44 eumenorrheic female athletes. When compared to eumenorrheic athletes, amenorrheic athletes had higher levels of plasma cholesterol (5.47 +/- 0.17 vs. 4.84 +/- 0.12 mmol/L, P = 0.003), triglyceride (0.75 +/- 0.06 vs. 0.61 +/- 0.03 mmol/L, P = 0.046), low-density lipoprotein (LDL; 3.16 +/- 0.15 vs. 2.81 +/- 0.09 mmol/L, P = 0.037), high-density lipoprotein (HDL; 1.95 +/- 0.07 vs. 1.73 +/- 0.05 mmol/L, P = 0.007), and HDL2 (0.84 +/- 0.06 vs. 0.68 +/- 0.04 mmol/L, P = 0.02) cholesterol. Plasma LDL/HDL cholesterol ratios, very low-density lipoprotein and HDL3 cholesterol, and apolipoprotein A-I and A-II levels were similar in the two groups. Amenorrheic athletes consumed less fat than eumenorrheic subjects (52 +/- 5 vs. 75 +/- 3 g/day, P = 0.02), but similar amounts of calories, cholesterol, protein, carbohydrate, and ethanol. HDL cholesterol levels in amenorrheic subjects correlated positively with the percent of dietary calories from fat (r = 0.42, n = 23, P = 0.045) but negatively with the percent from protein (r = -0.49, n = 23, P = 0.017). Thus, exercise-induced amenorrhea may adversely affect cardiovascular risk by increasing plasma LDL and total cholesterol. However, cardioprotective elevations in plasma HDL and HDL2 cholesterol may neutralize the risk of cardiovascular disease in amenorrheic athletes.

Adult↗

Hypoleptinemia in women athletes: absence of a diurnal rhythm with amenorrhea.

The possibility that chronic nutritional deficiency alters leptin regulation and its link to reproductive function was investigated by determining serum leptin levels during a 24-h period with controlled nutrient intake in highly trained athletes with and without menstrual cyclicity and in BMI-matched cycling sedentary controls (n = 8 per group). Our data show that 24th leptin levels were reduced equally (3-fold, P < 0.001) in both cyclic and amenorrheic athletes as compared to controls. Low leptin levels in the athletic groups were consistent with their reduction in body fat (r = 0.91, P < 0.0001) relative to BMI, but were also influenced by the presence of low insulin (r = 0.70, P < 0.001) and elevated cortisol (r = -0.65, P < 0.001) levels. A diurnal pattern of 24h leptin levels, with an approximate 50% rise (P < 0.001) from nadir (0900h) to peak (0100h), was present in normally cycling athletes and controls and was strikingly absent in amenorrheic athletes. The absolute increase in leptin levels from nadir to peak was directly related to insulin excursions in response to meals (r = 0.60, P = .002) and inversely related to the amplitude of the 24h cortisol rhythm (r = -0.70, P = .0002). These findings are consistent with a link between the functionality of adipocytes, nutritional status, and integrity of the reproductive axis in humans.

Adipose Tissue↗

Decreased nitric oxide levels and bone turnover in amenorrheic athletes with spinal osteopenia.

Amenorrheic athletes have been likened to postmenopausal women, with low estrogen levels and osteopenia. It has been suggested that estrogen exerts its antiresorptive actions on bone via a nitric oxide (NO)-dependent mechanism. This study investigated whether the mechanism of bone loss in amenorrheic athletes is similar to that of postmenopausal women with reduced NO levels and high bone turnover. Eleven amenorrheic athletes, 15 eumenorrheic athletes, and 10 sedentary controls were studied. Spine and hip bone mineral density was measured using dual-energy x-ray absorptiometry. Bone turnover was assessed by biochemical markers of formation (osteocalcin and bone-specific alkaline phosphatase) and resorption (deoxypyridinoline). NO metabolites were measured from 24-h urine samples using a chemiluminescence assay. Spine, but not hip, bone mineral density was reduced in the amenorrheic group, compared with the eumenorrheic (P = 0.0001) and control (P = 0.04) groups. Osteocalcin, bone-specific alkaline phosphatase, and deoxypyridinoline were similar in all groups. NO metabolites were lower in the amenorrheic group, compared with controls (P = 0.035), despite a higher dietary intake of nitrates. Unlike postmenopausal women, amenorrheic athletes do not have raised bone turnover but do have reduced NO metabolites and spinal osteopenia. The results show, however, that reduced NO production is a common denominator in both conditions and further support the importance of NO in estrogen-mediated protection of skeletal mass and strength.

Adult↗

Increased pulsatility, process irregularity, and nocturnal trough concentrations of growth hormone in amenorrheic compared to eumenorrheic athletes.

Amenorrheic athletes exhibit a spectrum of neuroendocrine disturbances, including alterations in the GH-insulin-like growth factor I (IGF-I) axis. Whether these changes are due to exercise or amenorrhea is incompletely characterized. The present study investigates spontaneous (overnight) and exercise-stimulated GH secretion and associated IGF-binding proteins (IGFBPs) in amenorrheic (AA; n = 5), and eumenorrheic athletes ( n = 5) matched for age, percent body fat (dual energy x-ray absorptiometry), training history, and maximal oxygen consumption. Each volunteer participated in two hospital admissions consisting of a 50-min submaximal exercise bout (70% maximal oxygen consumption) and an 8-h nocturnal sampling period. Deconvolution analysis of serum GH concentration time series revealed increases in the half-life of GH (60%) and the number of secretory bursts (85%) as well as a decrease in their half-duration (50%) and the mass of GH secreted per pulse (300%) in the AA cohort. Time occupancy at elevated trough GH concentrations was significantly increased, and GH pulsatility (approximate entropy) was more irregular in the AA group. During exercise, AA exhibited a reversal of the normal relationship between IGF-I and GH, and a 4- to 5-fold blunting of stimulated peak and integrated GH secretion. Fasting levels of plasma IGF-I, IGFBP-3, and IGFBP-1 appeared to be unaffected by menstrual status. In ensemble, this phenotype of GH release in amenorrheic athletes suggests disrupted neuroregulation of episodic GH secretion, possibly reflecting decreased somatostinergic inhibition basally, and reduced GHRH output in response to exercise compared with eumenorrheic athletes. Accordingly, we postulate that the amenorrheic state, beyond the exercise experience per se, alters the neuroendocrine control of GH output in amenorrheic athletes.

Adult↗

Hypertension in the athlete.

Athletes with hypertension are frequently encountered in clinical settings and during preparticipation examinations. This common condition merits special attention in athletes, as they have particular physiologic and sport-specific demands. Awareness of the pressor response to both isometric and isotonic exercise is valuable in managing hypertensive athletes. Recommendations regarding physical activity in hypertensive patients and clearance for sports participation among competitive athletes are reviewed. Nonpharmacologic measures and the use of customary antihypertensives in athletes is essential. However, knowledge of side-effect profiles and possible negative effects on exercise tolerance guide appropriate medication choices.

Adolescent↗

The athletic heart syndrome.

The cardiovascular system adapts to exercise. With conditioning, the heart modifies its physiologic and morphologic structure. When those changes occur in athletes seeking clearance for sports participation, they comprise the athletic heart syndrome. With detraining, many of those modifications normalize, which is a diagnostic feature of the athletic heart syndrome. It is important for practitioners who care for athletes to be cognizant of those adaptations and to differentiate them from pathologic changes that may warrant restriction from sports participation or place the athlete at risk for sudden cardiac death.

Adaptation, Physiological↗

Scaling behavior of VO2peak in trained wheelchair athletes.

PURPOSE: To examine the scaling behavior of peak oxygen uptake (VO2peak) in wheelchair athletes, adjusting for known covariates. METHODS: Body mass, VO2peak, and an estimate of adiposity (sum of four skinfolds) were determined in a sample of 45 highly trained wheelchair basketball and racing athletes. The participants were classified as possessing either "high" or "low" trunk stability and balance using recognized sporting classifications. A wheelchair ergometer was used to obtain the VO2peak measurements. The relationship between VO2peak and body mass was obtained via a nonlinear allometric model with the sum of four skinfolds, trunk stability and balance, and chronological age entered as covariates. RESULTS: The point estimate exponent for body mass was 0.82 (95% CI, 0.54-1.10). After controlling for the influence of body mass, adiposity, and age, the wheelchair athletes with greater trunk stability and balance had on average an 11% greater VO2peak. The regression model explained 54% of the sample variance in VO2peak. CONCLUSIONS: The obtained mass exponent of 0.82 is congruent with that predicted from the multiple-causes allometric cascade model and consideration of the physiological characteristics of spinal cord injured athletes. To compare the body size-independent VO2peak values of athletes within the study sample, the mass exponent of 0.82 may be adopted (i.e., mL x kg(-0.82) x min(-1)). The uncertainty in the point estimate, reflected in the relatively wide 95% CI, highlights the need for further research with larger samples to increase the precision of estimation.

Adolescent↗

T-wave and heart rate variability changes to assess training in world-class athletes.

PURPOSE: A decrease of electrocardiographic T-wave voltage with increasing training loads has been reported in elite endurance athletes and ascribed to training-related adaptation in sympathetic activity to the ventricles. A switch from vagal to sympathetic predominance in sino-atrial node regulation on going from low to peak training load has been reported in world-class rowers. In this study on world-class endurance athletes, we tested the hypothesis that training-induced variations in T-wave amplitude at higher training loads are paralleled by changes in HR spectral profile. METHODS: We studied eight male rowers of the Italian national team in the season culminating with the Rowing World Championship. Athletes were evaluated at 50 and 100% of training load, approximately 20 d before the World Championship, and during the World Championship, when the intensity was markedly reduced. We assessed T-wave maximum amplitude in chest lead V6 and cardiac autonomic regulation by power spectral analysis of R-R interval variability. RESULTS: The increase in training load from 50 to 100% was accompanied by a significant decrease in high frequency and a significant increase in low-frequency R-R variability (in normalized units) with a concomitant significant decrease in T-wave amplitude (microV). Reduction in training load during the World Championship resulted in a return of spectral profile to the level observed at 50% training load and in a partial recovery of T-wave amplitude. HR did not change significantly. CONCLUSIONS: In high-performance world-class athletes, training load simultaneously affects both ventricular repolarization and HR variability patterns possibly through variations in cardiac sympathetic modulation to the ventricles and the sino-atrial node. Information on concomitant changes in ventricular repolarization and autonomic cardiac regulation might be employed to tailor training protocols of elite athletes.

Adult↗

Hemorheology, sickle cell trait, and alpha-thalassemia in athletes: effects of exercise.

PURPOSE: This study investigated hemorheological parameters in response to exercise in sickle cell trait (SCT) athletes with or without alpha-thalassemia METHODS: Six athletes with SCT (HbAS), 7 athletes with SCT and alpha-thalassemia (HbASAT), and 10 control athletes (HbAA) performed a progressive and maximal exercise test on cycloergometer. Blood viscosity (etab), plasma viscosity (etap), etab at corrected hematocrit (etab45), hematocrit (Hct), and red blood cell (RBC) rigidity were assessed at rest, at maximal exercise and 24 h after exercise RESULTS: etab and etap were not different between the three groups at any time. Exercise induced changes in etab in HbAA and HbASAT groups but not in HbAS group. etab45 was higher in HbAS group compared with the other groups (P < 0.05), at rest and 24 h after exercise and increased only in HbAA group in response to exercise. HbAS group had lower Hct than HbAA group at any time. Hct and etap increased after exercise and declined under baseline values 24 h after exercise in all groups. RBC rigidity was higher in HbAS group compared with HbAA and HbASAT groups at any time, and was lower and higher at maximal exercise and 24 h after exercise, respectively, in all groups compared with resting values CONCLUSIONS: These results demonstrate that HbAS group is prone to higher RBC rigidity, which might lead to hemorheological alterations that are thought to participate to microcirculation disorders. However, these alterations are limited by the coexistence of alpha-thalassemia. Moreover, hemorheological parameters were not further impaired in SCT athletes with or without alpha-thalassemia in response to exercise. Training status might be protective from physiological stresses usually leading to sickling process in SCT carriers.

Adult↗

A biomechanical analysis of the long-jump technique of elite female amputee athletes.

PURPOSE: The purpose of this study was to investigate whether female lower-limb amputees conform to the established long-jump model and to compare the kinematics of the approach and take-off phases for elite female transfemoral and transtibial amputee long jumpers. METHODS: Eight female transfemoral and nine female transtibial amputee athletes were videotaped (sagittal plane movements at 50 Hz) from third-to-last step to take-off during the 2004 Paralympic Games long-jump finals. After digitizing and reconstruction of 2D coordinates, key variables were calculated at each stride and during contact with the take-off board. Additionally, approach speed during the run-up of each jump was recorded (100 Hz) using a laser Doppler device (LDM 300 C Sport, Jenoptik Laser, Jena, Germany). RESULTS: The transfemoral amputees had a consistently higher center of mass height on the last three steps before take-off than the transtibial amputees. However, at touch-down onto the take-off board, they lowered their center of mass excessively so that from touch-down to take-off, they were actually lower than the transtibial amputees. This resulted in a greater negative vertical velocity at touch-down and may have inversely affected their jump performance. CONCLUSION: Female transtibial athletes conformed to the long-jump model, although adaptations to this technique were displayed. Female transfemoral athletes, however, exhibited no relationship between take-off speed and distance jumped, which may be attributable to their excessive lowering of their center-of-mass height at touch-down onto the take-off board. It is recommended that coaches and athletes proceed with caution when trying to replicate techniques used by able-bodied athletes because adaptations to the constraints of a prosthesis should be considered.

Amputees↗