Male Strength Athletes Research Articles

Gendered perspectives on women’s anabolic–androgenic steroid (AAS) usage practices

BackgroundThe masculinizing effects from anabolic–androgenic steroid (AAS) appear to be different between men and women, leading to calls for more gender-specific information regarding women and AAS use. This study sought to gather perspectives from both men and women on the unique challenges surrounding women’s use of AAS, irrespective of their personal use. Secondly, the study interrogated how women’s AAS practices differ from those of men specifically.MethodsThe data presented in this paper come from a subsample of participants who participated in a larger study investigating women and performance and image enhancing drug (PIED) use in Australia. Participants were included in the current analysis if they were: (i) males or females who competed with or coached female strength athletes using AAS and (ii) female and male strength athletes who used AAS. The final sample comprised 21 participants of which there was a proportion of males (n = 7) and females (n = 7) using AAS.ResultsWomen’s choices in AAS selection were predominantly around oral compounds (e.g. Oxandrolone) as well as other PIEDs (e.g. Clenbuterol). Some women report the use of injectable AAS represents a change in the profile of the typical female user as it reportedly comes alongside drastic physical and psychological changes.ConclusionsThe unique challenges facing women who use AAS are largely isolation and stigma, with little evidence-based practice or education being available to them online or through peer-groups. Future work may consider piloting harm reduction strategies that may be co-designed with this group.

Athlete's Heart Assessed by Sit-Up Strength Exercises in Military Men and Women: The CHIEF Heart Study.

BackgroundGreater changes in cardiac structure and function in response to physical training have been observed more often in male athletes than in female athletes compared with their sedentary controls. However, studies for the sex-specific cardiac remodeling related to strength exercises in Asian athletes are rare.MethodsThis study included 580 men and 79 women, with an average age of 25 years, for a 6-month military training program in Taiwan. Both men and women attended a 2-min sit-up test to assess muscular strength after the training. The test performance falling one standard deviation above the mean (16%) was to define the superior eliteness of athletes. Cardiac structure and function were investigated by electrocardiography and echocardiography for men and women. Multiple logistic regression was used to determine the predictors of elite athlete status.ResultsIn men, greater QTc interval, left ventricular mass adjusted to body surface area (LVMI), lateral mitral E'/A' ratio and right ventricular systolic pressure, and lower diastolic blood pressure were independent predictors of elite strength athletes in the sit-up test [odds ratio (OR) and 95% confidence intervals: 1.01 (1.00, 1.02), 1.02 (1.00, 1.04), 1.45 (1.06, 1.98), 1.13 (1.06, 1.23), and 0.96 (0.93, 0.99), respectively. In contrast, in women, the greater right ventricular outflow tract dimension was the only independent predictor of elite strength athletes in the sit-up test [OR: 1.26 (1.04, 1.53)].ConclusionsIn the 2-min sit-up test, cardiac characteristics differ between elite male and female athletes. While greater QTc interval, LVMI, and diastolic function of left ventricle predict the eliteness of male strength athletes, greater right ventricular chamber size characterizes elite female strength athletes.

Comparing Predictive Equations To Measured Resting Energy Expenditure In Male Strength And Power Athletes

Comparing Predictive Equations To Measured Resting Energy Expenditure In Male Strength And Power Athletes

The Relationship Of Anabolic-Androgenic Steroids And Sexual Health Among Male Competitive Strength Athletes

The Relationship Of Anabolic-Androgenic Steroids And Sexual Health Among Male Competitive Strength Athletes

The Impact of the COVID-19 Pandemic on Male Strength Athletes Who Use Non-prescribed Anabolic-Androgenic Steroids.

Background: One sub-population potentially affected by the COVID-19 pandemic are strength athletes who use anabolic-androgenic steroids (AAS). We examined links between disruption in AAS use and training due to the pandemic and mental health outcomes in this population, hypothesising: (a) the pandemic would be linked with reduced training and AAS use; and (b) athletes perceiving greater impact on their training and AAS use would report increases in detrimental mental health outcomes.Methods: Male strength athletes using AAS (N = 237) from 42 countries completed an online questionnaire in May 2020. A sub-sample (N = 90) from 20 countries participated again 4 months later. The questionnaire assessed pre-pandemic and current AAS use and training, alongside several mental health outcomes.Results: At Time 1, most participants perceived an impact of the pandemic on AAS use (91.1%) and/or training (57.8%). Dependent t-tests demonstrated significant reductions in training frequency (t = 7.78; p < 0.001) and AAS dose (t = 6.44; p < 0.001) compared to pre-pandemic. Linear regression showed the impact of the pandemic on training was a significant positive predictor of excessive body checking (B = 0.35) and mood swings (B = 0.26), and AAS dose was a significant positive predictor of anxiety (B = 0.67), insomnia (B = 0.52), mood swings (B = 0.37). At Time 2, fewer participants perceived an impact of the pandemic on AAS use (29.9%) and/or training (66.7%) than at Time 1. Training frequency (t = 3.02; p < 0.01) and AAS dose (t = 2.11; p < 0.05) were depressed in comparison to pre-pandemic. However, AAS dose had increased compared to Time 1 (t = 2.11; p < 0.05). Linear regression showed the impact of the pandemic on training/AAS use did not significantly predict any mental-health outcomes. However, AAS dose was a significant negative predictor of depressive thoughts (B = −0.83) and mood swings (B = −2.65).Conclusion: Our findings showed impact of the pandemic on the training and AAS use, reflected in reduced training frequency and AAS dose. However, whilst we detected some short-term consequential effects on mental health, these did not appear to be long-lasting.

Sport and Venous Thromboembolism—Site, Accompanying Features, Symptoms, and Diagnosis.

The occurrence of venous thromboembolisms (VTE) in association with sporting activity has been described but not yet systematically explored. The aim of this study was to determine the sites at which VTE occur in athletes, the accompanying features, and the special features of the symptoms and diagnosis, so that physicians can take the findings into consideration. A search of the literature in the databases PubMed, Web of Science, and Cochrane in accordance with the PRISMA criteria, together with a search of Google Scholar up to 29 February 2020. No observational studies were identified. A total of 154 case descriptions were evaluated: 89 on upper-extremity deep vein thrombosis (DVT), 53 on lower-extremity DVT, and 12 on pulmonary embolisms with no evidence of thrombosis. Ninety-five percent of the upper-extremity DVT involved the region of the subclavian/axillary vein. Thoracic outlet syndrome (38%), hereditary thrombophilia/a family history of VTE (16%), intensive training (12%), and the use of oral contraceptives (7%) were identified as accompanying features. The upper-extremity DVT occurred mainly in male strength athletes and ball sports players. The lower-extremity DVT were located in the lower leg/knee (30%), the thigh (19 %), or occurred in combination in the lower leg-to-pelvis region (30 %). The features accompanying lower-extremity DVT were hereditary thrombophilia/a family history of VTE (30%), trauma (25%), immobilization (21%), and the use of oral contraceptives (11%). The lower-extremity DVT were found in endurance sports and ball sports. The symptoms may be obscured by sport-specific symptoms/trauma, and diagnosis is often delayed. Early D-dimer determination is useful and is complemented by diagnostic imaging. VTE are found in association with sports. The background factors, the sites of VTE, the types of sports involved, and the accompanying features are all important to know. The symptoms may be obscured, and it may be difficult to reach the correct diagnosis. The possible presence of DVT must be borne in mind.

Is there an athlete’s artery? A comparison of brachial and femoral artery structure and function in male strength, power and endurance athletes

ObjectivesExercise places physiological demands upon the cardiovascular system, subsequently leading to adaptations in structure and function. Different exercise modalities (endurance, strength and power) lead to distinct hemodynamic demands and, possibly, different patterns of adaptation. Our aim was to assess and compare brachial and femoral artery function and structure in elite level athletes engaged in endurance, strength and power sports. Designcross sectional comparison. Methods30 male elite athletes (runners n=10, powerlifters n=11, weightlifters n=9) and 23 healthy controls were recruited. Brachial and femoral arterial diameters were assessed using ultrasound. Arterial function (brachial and femoral arteries) was determined using the flow mediated dilation (FMD) technique and body composition using body mass index (BMI) and body surface area (BSA). ResultsWeightlifters had significantly larger brachial arterial diameters compared to controls (4.39±0.34 vs 3.86±0.42mm, p<0.01). As weightlifter and power athletes had significantly higher body mass, BMI and BSA, we adjusted diameter for BSA. BSA-correction ameliorated differences in brachial artery resting diameters between athletes and controls. However, BSA-corrected femoral artery diameter was significantly larger in runners compared to controls (3.51±0.28 vs 3.25±0.34mm, p<0.05). There were no differences in brachial FMD between groups. Femoral artery FMD was significantly higher in runners and weightlifters compared to controls (p<0.05 for both groups). ConclusionsHeterogeneous, limb-specific structural and functional vascular adaptation is evident in athletes, which may be influenced by exercise modality. Further, vascular remodelling relates to differences in body shape, specifically body composition, which should be accounted for when comparing athletes.

Assessment of left ventricular systolic function by non-invasive pressure-strain loop area in young male strength athletes

BackgroundThe health of athletes has been recognized as a worldwide public concern with more reported sudden cardiac deaths (SCD). Therefore, early detection of abnormal heart function in athletes can help reduce the risk of exercise. A novel valid non-invasive method to evaluate left ventricular (LV) myocardial work (MW) using LV pressure-strain loop (PSL), was used in this paper to explore LV systolic function in young male strength athletes.MethodsThirty-six professional young male strength athletes (the athlete group) and 32 healthy, age-matched young men (the control group) were involved in the study. The LVMW parameters were calculated as the area of PSL by two-dimensional speckle tracking echocardiography (2D-STE) and peak systolic LV pressure. The differences between two groups of data and the predictive efficacy of MW parameters for LV systolic function were analyzed.ResultsThe athlete group had significantly higher values of global wasted myocardial work (GWW) and peak strain dispersion (PSD) than did the control group (P<0.05). Global myocardial work index (GWI), global constructive myocardial work (GCW) and global longitudinal strain (GLS) were lower in the athlete group than that in the control group, although statistical significance was not reached (P>0.05). Due to the proportion of GWW and GCW, statistically significant reduction was found in global myocardial work efficiency (GWE) in the athlete group. Conventional echocardiography parameters were well correlated with GWW and GWE (P<0.05). The best predictor of LV myocardial contractile performance in the athletes using receiver operating characteristic curve (ROC) was GWE, with the area under ROC (AUC) of 0.733, sensitivity of 83.3% and specificity of 59.4%.ConclusionsSubclinical changes have appeared in the hearts of young male strength athletes after long-term intensive exercise and LVMW parameters by PSL play an important role in the evaluation of athlete’s LV contractile performance.

Dietary Knowledge as A Determinant of The Dietary Practices and Nutrition Status of Amateur Male Strength-Athletes

Male strength-athletes have special dietary needs yet if they have inadequate dietary knowledge it may result in them adopting poor dietary practices. This can both lead to a state of undernutrition or over-nutrition and predispose the strength-athletes to diet-related chronic diseases. The objective of this study was to therefore establish the influence of dietary knowledge on the dietary practice and nutrition status of amateur strength-athletes. Data was collected at the Railway Gymnasium in Nairobi County on the nutrition status, dietary knowledge and dietary practice from 162 study participants. Nutrition status was determined using 3 anthropometric indices; the Body Mass Index, body fat percentage and the Waist–Height Ratio. Dietary knowledge was measured using a knowledge assessment quiz and dietary practice was assessed using a Food Frequency questionnaire. The data collected was analysed using descriptive and inferential statistics. A P-value of &lt;0.05 was considered significant in all the analyses. The mean Body Mass Index of the study participants was 25.72 (±0.41) which is classified as overweight. The mean body fat percentage was 14.09 (±0.48) and the mean waist-height ratio was 0.49 (±0.004) both of which are classified as healthy. Knowledge score of the study participants was significantly associated with their body fat percentage (χ2=10.814, P=0.013). The nutrition status of the study participants was influenced among all 3 indices by the frequency of consumption of red meat; body fat percentage (P=0.041), Body Mass Index (P=0.001) and waist-height ratio (P=0.004). The study concluded that dietary knowledge is a significant determinant of dietary intake and the nutrition status of amateur male strength-athletes.

Strength Athletes Are Capable to Produce Greater Muscle Activation and Neural Fatigue During High-Intensity Resistance Exercise Than Nonathletes

Acute neuromuscular responses to maximum versus forced repetition (FR) knee extension resistance exercises (4 sets of 12 repetitions [reps] with a 2-minute recovery between the sets) were examined in 4 male strength athletes (SAs) and 4 nonathletes. Maximum repetition (MR) sets were performed to voluntary exhaustion (12 repetition maximum [RM]), whereas in the FR sets, the load was greater (8RM) and the set was continued after voluntary fatigue with 4 additional assisted reps. Maximal isometric force and electromyogram (EMG) activity of the knee extensors were measured before and after the exercise, as well as 2 recovery days after the exercise. Electromyogram activity was also measured during the actual concentric phases of the knee extensions. Both loading protocols in both groups led to decreases in isometric force, but no significant changes were observed in EMG activity during isometric actions at any time points. However, the difference between the 2 loading protocols and experimental groups was observed in muscle activity during the concentric phases of the knee extensions. As expected, EMG activity increased in both groups throughout the MR sets when compared with the first repetitions of the sets. Only in SAs, EMG activity decreased significantly at the end of the FR sets. The results suggest that experienced SAs were capable to activate their muscles to a greater extent than their non-strength-trained counterparts indicated by neural fatigue during the FR exercise. Greater motor unit activation in SAs than in nonathletes may be due to training-induced neural adaptation, which manifested during fatiguing exercise. The present study suggests that FRs are an efficient training protocol to overload the neuromuscular system especially in SAs.

Acute Hormonal Responses to Heavy Resistance Exercise in Strength Athletes Versus Nonathletes

The aim of the present study was to investigate acute hormonal and neuromuscular responses and recovery in strength athletes versus nonathletes during heavy resistance exercise performed with the forced and maximum repetitions training protocol. Eight male strength athletes (SA) with several years of continuous resistance training experience and 8 physically active but non-strength athletes (NA) volunteered as subjects. The experimental design comprised two loading sessions: maximum repetitions (MR) and forced repetitions (FR). MR included 12-RM squats for 4 sets with a 2-min recovery between sets. In FR the initial load was higher than in MR so that the subject could lift approximately 8 repetitions by himself and 4 additional repetitions with assistance. Before and after the loading protocols, blood samples were drawn to determine serum testosterone, free testosterone, cortisol and growth hormone concentrations, and blood lactate. Maximal voluntary isometric force and EMG activity of the leg extensors was measured before and after the loading as well as 24 and 48 hrs after the loading. The concentrations of the hormones measured increased significantly (p < .01-.001) after both loadings in both groups. The responses tended to be higher in FR than the MR loading and the increases of testosterone concentrations were significantly (p < .01) greater in both loadings in SA than in NA. Both loading protocols in both groups also led to neuromuscular fatigue observable with significant acute decreases in isometric strength by 32-52% (p < .001) and in maximal iEMG (p < .05-01) associated with large increases in blood lactate. These data suggest that, at least in experienced strength athletes, the forced-repetition protocol is a viable alternative to the more traditional maximum-repetition protocol and may even be a superior approach.

Effects of androgenic-anabolic steroids on apolipoproteins and lipoprotein (a)

Objectives: To investigate the effects of two different regimens of androgenic-anabolic steroid (AAS) administration on serum lipid and lipoproteins, and recovery of these variables after drug cessation, as indicators of...

The effects of anabolic-androgenic steroids upon resting and peak exercise left ventricular heart wall motion kinetics in male strength and power athletes

Previous investigations reported alterations in myocardial fibres and systolic function associated with anabolic-androgenic steroid consumption by athletes. Advances in bio-medical technology have allowed further investigation in assessing the possible effects of anabolic-androgenic steroids on gross left ventricular kinetics. Twenty-three male strength and power athletes with a past and current history of anabolic-androgenic steroid consumption (x 46 days, range 28 days to 70 days), were compared to 23 controls. Testing consisted of resting and immediate post-exercise transthoracic left ventricular wall cardiokymograms. Statistical results identified no difference over time between groups or condition. Cardiokymographic waveform analysis found 32.61% of all (n =184) waveforms to be abnormal (Type II, n = 56 or Type III, n = 4). There were 14 treatment subjects (60.87%) who demonstrated an abnormal waveform as compared to 9 controls (39.13%). A significant difference (p < or = 0.01) in the overall proportions of waveform types was identified where the treatment group exhibited 41.30% abnormal waveforms, compared to 23.91% by controls. Additionally, two athletes (1 treatment, 1 control) demonstrated abnormal left ventricular wall motions (Type III) analogous to impaired left ventricular performance. The results indicated: (a) highly strength trained athletes with no history of anabolic-androgenic steroid usage exhibited an unexpected high incidence of Type II waveforms (28.26% pre/23.91% post); (b) a comparable group of strength trained athletes using anabolic-androgenic steroids exhibited a significantly higher percentage of abnormal waveforms as compared to controls (34.78% pre/37.21% post). Based on these results, high intensity strength training with and without anabolic-androgenic steroid supplementation induced alterations in the left ventricular wall motion.

Muscle hypertrophy, hormonal adaptations and strength development during strength training in strength-trained and untrained men.

Hormonal and neuromuscular adaptations to strength training were studied in eight male strength athletes (SA) and eight non-strength athletes (NA). The experimental design comprised a 21-week strength-training period. Basal hormonal concentrations of serum total testosterone (T), free testosterone (FT) and cortisol (C) and maximal isometric strength, right leg 1 repetition maximum (RM) of the leg extensors were measured at weeks 0, 7, 14 and 21. Muscle cross-sectional area (CSA) of the quadriceps femoris was measured by magnetic resonance imaging (MRI) at weeks 0 and 21. In addition, the acute heavy resistance exercises (AHRE) (bilateral leg extension, five sets of ten RM, with a 2-min rest between sets) including blood samples for the determination of serum T, FT, C, and GH concentrations were assessed before and after the 21-week training. Significant increases of 20.9% in maximal force and of 5.6% in muscle CSA in NA during the 21-week strength training period were greater than those of 3.9% and -1.8% in SA, respectively. There were no significant changes in serum basal hormone concentrations during the 21-week experiment. AHRE led to significant acute decreases in isometric force and acute increases in serum hormones both at weeks 0 and 21. Basal T concentrations (mean of 0, 7, 14 and 21 weeks) and changes in isometric force after the 21-week period correlated with each other (r=0.84, P<0.01) in SA. The individual changes in the acute T responses between weeks 0 and 21 and the changes in muscle CSA during the 21-week training correlated with each other (r=0.76, P<0.05) in NA. The correlations between T and the changes in isometric strength and in muscle CSA suggest that both serum basal testosterone concentrations and training-induced changes in acute testosterone responses may be important factors for strength development and muscle hypertrophy.

P2906 Overlapping in the cardiopulmonary exercise testing parameters of male patients with hypertrophic cardiomyopathy and male strength athletes

P2906 Overlapping in the cardiopulmonary exercise testing parameters of male patients with hypertrophic cardiomyopathy and male strength athletes

Androgenic-Anabolic Steroid—Induced Body Changes in Strength Athletes

BACKGROUND: Some strength athletes use androgenic-anabolic steroids (AAS) to improve body dimensions, though the drugs' long- and short-term effects have not been definitively established.OBJECTIVE: This study sought to investigate the short- and long-term effects of AAS self-administration on body dimensions and total and regional body composition.DESIGN: This prospective, unblinded study involved 35 experienced male strength athletes: 19 AAS users (drugs were self-administered) and 16 nonuser controls engaged in their usual training regimens. At baseline, 8 weeks, and 6 weeks after AAS withdrawal (for AAS users) circumferences were measured at 10 sites, and skinfolds measured at 8 sites. To assess differences in AAS regimens, 9 subjects took AAS for 8 weeks (short-AAS) and 10 athletes took AA S for 12 to 16 weeks (long-AAS). Body composition and anthropometry were assessed at baseline, at the end of AAS use, and 6 weeks later. Lean body mass (LBM) was calculated from body weight and percentage fat. Total and regional body composition was measured by dual-energy x-ray absorptiometry.RESULTS: AAS use increased users' body weight by 4.4 kg and LBM by 4.5 kg, and produced increases in several circumferences. Percentage of fat decreased (17.0% to 16.0%), but fat mass remained unchanged. Changes persisted 6 weeks after drug withdrawal but were not less than those taken at 8 weeks. Bone-free lean mass of all regional body parts increased in subjects taking AAS, but fat mass was unaffected. Short- and long-term AAS users did not differ in any parameter measured at 8 weeks or after drug withdrawal.CONCLUSION: In AAS users, 8 weeks of self-administered AAS increased body weight, lean body mass, and limb circumferences, but decreased percentage fat compared with controls. Changes remained 6 weeks after drug withdrawal, though for some measurements only partially. AAS stimulated the bone-free lean mass of all body parts, but it did not affect fat mass. Short-term and long-term AAS administration produced comparable effects.

Recovery of skeletal muscle contractility after high- and moderate-intensity strength exercise.

To examine neuromuscular fatigue and recovery, ten male strength athletes [mean (SE) 27.5 (1.4) years] performed a moderate- and a high-intensity strength exercise protocol. In the high-intensity protocol, the load was 100% of the subject's three-repetition maximum (3-RM) for squats and front squats, and 100% of the subject's 6-RM for knee extensions. In the moderate-intensity protocol, the load was 70% of the high-intensity protocol, and both protocols lasted 90 min. The contractile properties of the leg extensor muscles were tested using isokinetic knee extensions, electrical stimulation, and squat jumps. Tests were done before exercise, 5-20 min after exercise, and frequently for 33 h after exercise. The decrements in knee extension performance were greater after the high-intensity protocol (12-14%), as compared to the moderate-intensity protocol (6-7%, P < 0.01). Similar decrements were seen in squat-jumping performance after the high-intensity protocol. Decrements in electrically evoked force were also greatest after the high-intensity protocol (P < 0.05), and were more pronounced at 20 Hz stimulation than at 50 Hz stimulation (P < 0.05). The recovery of performance showed a biphasic pattern, with a rapid recovery within the first 11 h after exercise, followed by a leveling off or a second drop in performance 11-22 h after exercise. All variables were back to baseline by 3 h after the moderate-intensity protocol, while all variables were back to baseline by 33 h after the 100% protocol. The role of structural changes (excitation-contraction coupling and contractile proteins) in the long-lasting performance decrements seen after the high-intensity protocol is discussed.

Assessment of attentional bias and mood in users and non-users of anabolic-androgenic steroids

Forty-six male strength athletes took part in a study to measure the effects of anabolic-androgenic steroids on attentional bias to aggressive cues. They were 16 current users of anabolic steroids, 16 former users and 14 non-users. Testosterone, deca-durabolin and anadrol were the three most commonly taken steroids during the last cycle. Users generally took 2–3 drugs during each cycle; the average cycle lasted 8–11 weeks and they had completed 3–4 cycles. The subjects completed visual analogue scales of current feelings and were presented with a modified Stroop Colour Word Conflict Task containing sets of neutral, verbally aggressive and physically aggressive words. Current users tended to rate themselves more negatively. Users took longer than former users to name the colours of all word sets but there were no significant differences between word sets. Therefore, attentional bias did not differ between groups but current steroid use produced subtle mood changes and slowed performance compared to users not currently taking steroids.

Acute hormonal responses to two different fatiguing heavy-resistance protocols in male athletes

To examine endogenous hormonal responses to heavy-resistance exercise, ten male strength athletes performed two fatiguing but different types of sessions on separate days. In session A the loads for the leg extensor muscles in the squat-lift exercise were maximal so that the subjects performed 20 sets at 1 repetition maximum (RM) (20 x 1 RM x 100%), whereas during session B the loads were submaximal (70%) but the subjects performed each of the 10 sets until the RM (i.e., 10 repetitions/set or 10 x 10 x 70%). The recovery time between the sets was always 3 min. A decrease of 10.3 +/- 4.7% (P < 0.001) occurred in the squat-lift in 1 RM during session A, whereas session B led to a decrease of 24.6 +/- 18.9% (P < 0.001) in 10 RM. Increases in the concentrations of serum total and free testosterone (P < 0.05 and 0.05, respectively), cortisol (P < 0.001), and growth hormone (GH, P < 0.001) were observed during session B, whereas the corresponding changes during session A were statistically insignificant except for the relatively slight increase (P < 0.01) in serum GH level. The significant (P < 0.001) increase in blood lactate concentration during the two sessions correlated significantly (P < 0.01) with the increase in serum GH concentration. The morning values of serum testosterone and free testosterone were significantly (P < 0.05-0.001) lowered on the 1st and 2nd rest days after the sessions.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum hormones in male strength athletes during intensive short term strength training

Training-induced adaptations in the endocrine system and strength development were investigated in nine male strength athletes during two separate 3-week intensive strength training periods. The overall amount of training in the periods was maintained at the same level. In both cases the training in the first 2 weeks was very intensive: this was followed by a 3rd week when the overall amount of training was greatly decreased. The two training periods differed only in that training period I included one daily session, while during the first 2 weeks of period II the same amount of training was divided between two daily sessions. In general, only slight and statistically insignificant changes occurred during training period I in mean concentrations of serum hormones examined or sex hormone-binding globulin as well as in maximal isometric leg extensor force. However, during training period II after 2 weeks of intensive strength training a significant decrease (P less than 0.05) was observed in serum free testosterone concentration [from 98.4 (SD 24.5) to 83.8 (SD 14.7) pmol.l-1] during the subsequent week of reduced training. No change in the concentration of total testosterone was observed. This training phase was also accompanied by significant increases (P less than 0.05) in serum luteinizing hormone (LH) and cortisol concentrations. After 2 successive days of rest serum free testosterone and LH returned to (P less than 0.05) their basal concentrations. Training period II led also to a significant increase (P less than 0.05) [from 3942 (SD 767) to 4151 (SD 926) N] in maximal force.(ABSTRACT TRUNCATED AT 250 WORDS)