The Journal of sports medicine and physical fitness

Published by Edizioni Minerva Medica
Online ISSN: 1827-1928
Print ISSN: 0022-4707
Publications
The present study examined the VO2 response to middle-distance track running events of 800 m, 1500 m and 3000 m and investigated the relationship between the speed of the VO2 response ((1) and subsequent race performance. Trained 3000-m (n = 8), 1500-m (n = 10) and 800-m (n = 8) male track athletes performed a laboratory GXT plus a run at 14 km x h(-1) and multiple race time trials. For each subject, a bi-exponential model fit from 20 s was used to categorise the O2 response for the best performed track run and also the treadmill run at 14 km x h(-1). Faster (1 values were noted the shorter the track event, with values of 14, 18.5 and 20.8 s for 800-, 1500- and 3000-m events, respectively. ANOVA results revealed that differences in (1 were significant (P < 0.05) for the 800- and 3000-m, but not for the 800- and 1500-m (P = 0.06) or 1500- and 3000-m events (P = 0.15). Only 1500-m race performance was significantly correlated to race (1 (r = 0.71). Values for (1 at an absolute velocity treadmill run (14 km x h(-1)) did not differ significantly between different events and were not correlated to race performance for any event. From pooled data for all three events, significant correlations (P < 0.01) were noted between tau1 and the speed over the first 800-m (r = -0.54 to -0.68). There was a trend for faster (1values the shorter the track event. The significant correlation between tau1 and initial starting velocity suggests this may be attributed to the faster starting velocity of the shorter track events, rather than any differences between athletes per se.
 
The running velocities associated to lactate minimum (V(lm)), heart rate deflection (V(HRd)), critical velocity (CV), 3.000 m (V(3000)) and 10 000 m performance (V10km) were compared. Additionally the ability of V(lm) and V(HRd) on identifying sustainable velocities was investigated. Twenty runners (28.5+/-5.9 y) performed 1) 3,000 m running test for V3000; 2) an all-out 500 m sprint followed by 6x800 m incremental bouts with blood lactate ([lac]) measurements for V(lm); 3) a continuous velocity-incremented test with heart rate measurements at each 200 m for V(HRd); 4) participants attempted to 30 min of endurance test both at V(lm)(ETV(lm)) and V(HRd)(ETV(HRd)). Additionally, the distance-time and velocity-1/time relationships produced CV by 2 (500 m and 3 000 m) or 3 predictive trials (500 m, 3,000 m and distance reached before exhaustion during ETV(HRd)), and a 10 km race was recorded for V10km. The CV identified by different methods did not differ to each other. The results (m.min(-1)) revealed that V(lm) (281+/-14.8)<CV (292.1+/-17.5)=V10km (291.7+/-19.3)<V(HRd) (300.8+/-18.7)=V3000 (304+/-17.5) with high correlation among parameters (P<0.001). During ETVlm participants completed 30 min of running while on the ETV(HRd) they lasted only 12.5+/-8.2 min with increasing [lac]. We evidenced that CV and Vlm track-protocols are valid for running evaluation and performance prediction and the parameters studied have different significance. The V(lm) reflects the moderate-high intensity domain (below CV), can be sustained without [lac] accumulation and may be used for long-term exercise while the V(HRd)overestimates a running intensity that can be sustained for long-time. Additionally, V3000 and V(HRd) reflect the severe intensity domain (above CV).
 
The possible variations in cardiac dynamics induced by fructose-1.6-diphosphate (FDP) were investigated during an isometric exercise in healthy volunteers. Echocardiographic recordings were carried out using the following method: (a) 20 seconds of restone; (b) intake of FDP (first test) or placebo (second test); (c) 20 seconds of rest-two; (d) 60 seconds of hand-gripping; (e) 120 seconds of recovery. No significant differences were noticed between the SAP (systemic arterial pressure) and the HR (heart rate) trends recorded after FDP and placebo. In contrast SI (systolic index) decreased significantly after FDP in comparison with the placebo test. It is suggested that FDP is the main cause of this increase in cardiac inotropism.
 
Aim: This study aimed to investigate the response of blood antioxidants and biomarkers of lipid peroxidation, muscle damage and inflammation to a 1000m kayak trial in elite male kayakers. Methods: Enzymatic (superoxide dismutase [SOD], glutathione reductase [Gr] and glutathione peroxidase [GPx] activities) and non-enzymatic (total antioxidant status [TAS], uric acid, α-tocopherol, α-carotene, β-carotene, lycopene and lutein and zeaxanthin) antioxidants, thiobarbituric acid reactive substances (TBARS), creatine kinase (CK), interleukin-6 (IL-6) and cortisol were determined in 15 elite male kayakers before and 15 min after a 1000-m kayak simulated race. Results: Both enzymatic and non-enzymatic antioxidants were unaffected by exercise, with the exception of α-carotene which decreased (P=0.013). Uric acid levels were incremented following exercise (P=0.016). The acute exercise resulted in a significant decrease in TAS (P=0.001) and in an increase in CK (P=0.023), TBARS (P<0.001) and IL-6 (P=0.028). Conclusion: Our study suggests that a 1000-m kayak simulated race induces oxidative stress and damage in highly-trained kayakers.
 
With the guidance of the International Olympic Committee (IOC) the Olympic Council of Asia (OCA) introduced doping tests at the 1986 10th Asian Games at Seoul, Korea. From September 21st to October 5th, 1986, 585 samples were tested for stimulants, narcotics, anabolic steroids and beta-blockers by gas chromatography-mass spectrometry, high pressure liquid chromatography and fluorescence polarization immuno assay (TDX system by Abbott Lab.). These tests covered about 100 different drugs and another 400 as metabolites. Information about 1000 different drugs were required to interpret the drug screening data properly. The test results and outcome of findings are summarized. 3.2% of the samples were found to contain a banned drug and doping offenders were penalized accordingly.
 
The purpose of this study was to examine the effects of the interval training on metabolic parameters at maximal work and at the anaerobic threshold in 11 year olds. The subjects were five healthy male children. They trained outdoor for 50 min a day, five times a week for six weeks, using interval work at 25 and 50% above their anaerobic threshold. Before and after training program, they performed a progressive exercise test on a cycle ergometer. During the last 15 sec of each power output measurements were made of oxygen uptake (VO2), carbon dioxide output (VCO2), heart rate (HR), ventilation (VE), ventilatory equivalent for oxygen (VEO2) and ventilatory equivalent for carbon dioxide VECO2). Following training, the group increased their anaerobic threshold (expressed as %VO2max) significantly (P less than 0.05) during the progressive exercise test, by 22%. Also at the anaerobic threshold level, increases were observed following training in CO2 output (VCO2-AT) and respiratory exchange ratio (R). Oxygen uptake (VO2, l.min-1) was increased by 19%, but the difference was not significant (P greater than 0.05). Maximal ventilatory equivalent for (VECO2max) decreased significantly (P less than 0.05). Maximal heart rate was reduced significantly (P less than 0.05). We conclude that training led to an increase of both anaerobic and aerobic metabolism, at any submaximal work above the anaerobic threshold, for this specific age group.
 
Soccer is characterized by high injury rates that necessitate interventions for its reduction. The "11" is a multi-modal preventive program that was developed to reduce injury rate. However, outcomes on the effectiveness of the program are not unambiguous and data for the largest group at risk (i.e., male adult amateur players) are missing. The study aims to assess the injury rate in male adult amateur soccer players of different levels and to evaluate the effectiveness of the prevention program the "11". Three amateur soccer teams participated in the study during the first round of a competition season. Two teams played at a regional level (6th Italian league) and one team at a provincial level (7th Italian league). The regional league is of a higher skill level compared to the provincial league. Duration and frequency of training and match sessions and the occurrence of time-loss injuries were recorded. One team of the 6th league performed an injury prevention program. The total injury rate for the intervention and the control team in the 6th league was 3.3 (CI 0.7-5.9) and 4.3 (CI 1.3-7.3) injuries/1000 h, respectively (P=0.841). The 6th league control team tended to have a lesser injury rate compared to the 7th league team (P=0.081). The relative risk was 2 fold higher in the 7th compared to the 6th league team (P=0.0285 one tailed). Present results show that injury rate in amateur soccer depended rather on the skill level than the prevention program. In this study the prevention program the "11" was not shown to be highly effective in soccer player of intermediate level (i.e., 6th Italian league).
 
The purpose of this study was to determine the association of static strength with motor performance of 7 through 11 year old boys (N = 60) after accounting for differences in physique, i.e., body size, shape, and composition. Static strength measures included thigh extension, leg extension and plantar flexion measured by electronic transducer and back lift, leg lift, and right and left grips measured by spring dynamometer. Measures of body composition consisted of fat estimated from triceps, subscapsular and calf skinfolds, and fat-free body weight estimated from potassium-40 measurements. Body structure consisted of skeletal widths, and segment girths, lengths and volumes. The dependent variables were vertical jump, standing broad jump, 50-yard dash, 600-yard run and mile run. The measures of strength increased the variance accounted for from 10 to 23% over that when body size, composition and structure were used without strength. An exception was vertical jump where no increase in the variance accounted for was found with the addition of strength variables. The regression equations determined for the sample of 60 boys rendered multiple R's ranging from 0.64 (mile run) to 0.75 (50-yard dash). It was concluded that strength has a significant relation to motor performance and that its contribution can be better assessed after accounting for differences in body size, shape, and composition.
 
Rationale and objectives: To highlight the special frequency of cases of rhabdomyolysis related to the practice of indoor cycling and to define the characteristics, course, and outcome of this disease. Patients and methods: Retrospective review of clinical histories of patients diagnosed with rhabdomyolysis after indoor cycling in our unit from January 2012 to April 2013. Results: Eleven patients were analyzed. All patients, regardless of the degree of previous physical training, were diagnosed after a first session of indoor cycling. Mean age was 27.63 years (SD=5.74). Fifty-four percent were women. Creatine kinase (CK) levels gradually decreased in response to rest and intensive intravenous hydration. Only in two cases was renal failure observed, and in none were electrolyte disorders, disseminated intravascular coagulation (DIC) or compartmental syndrome detected. Conclusions: A first session of indoor cycling has become a common cause of rhabdomyolysis secondary to the physical exercise in recent years, which should alert those responsible for teaching this sport of the need for a gradual start under adequate hydration and environmental conditions, because although the condition has a benign course with adequate treatment and the complication rate is low, there are patients with increased susceptibility to very high CK blood levels requiring hospitalization for treatment and follow-up of possible complications.
 
The purpose of this study was to determine the anaerobic threshold (AT) of 11 year olds. The secondary purpose was to examine the regression of ventilation (V̇E) on V̇CO2 as work rate increased from rest to the AT for that age group. Six healthy male children were studied at rest and during cycling on a bicycle ergometer, with work rate incremented every one minute up to each subjects' maximal O2 uptake (V̇O2max). The average child reached the AT at 58.53 ± 0.41% V̇O2max (V̇O2 = 0.91 ± 0.12 l·min-1). The ventilatory equivalents for O2 (V̇E/V̇O2) and CO2 (V̇E/V̇CO2) at the AT were 25.19 ± 0.91 and 27.29 ± 1.34, respectively. The regression of V̇E (BTPS) on V̇CO2 (STPD) and V̇O2 (STPD), from rest to the AT, were significant (p < 0.05) and linear with common regression coefficients (bc) of 22.72 ± 1.34 and 24.72 ± 0.41, respectively. The corresponding intercepts were 3.44 ± 0.51 and 1.83 ± 0.50 l·min-1. The lower 95% confidence limit for the V̇E-V̇CO2 relationship at V̇CO2 of zero was significantly (p < 0.05) positive, implying a reduction in the ventilatory equivalent for CO2 as work rate increased from rest to the AT. Since the rate constant of exchange between different pools of CO2 are not equivalent between rest and exercise nor equivalent between individuals, the varying of V̇E/V̇CO2 does not well represent the precise response of V̇E to increasing V̇CO2. Therefore, it is believed that the common regression coefficient (bc) better represents the characteristics of ventilatory control during exercise.
 
Variation in anthropometric characteristics and somatotype of female figure skaters by level of competition and discipline was examined. Experimental design: ANCOVA with age as the covariate was used to compare the anthropometry of skaters by level (test stream, pre-elite, elite) and discipline (free, dance, pair), while MANCOVA was used to compare somatotype. Setting: purposive sampling reflecting the skating population by level and discipline was used to recruit skaters in 4 American, and 7 Canadian figure skating clubs. Participants: a total of 161 competitive female figure skaters 11-22 years of age (15.7+/-2.4 years) comprised the sample. Measures: a battery of 15 anthropometric dimensions was taken on each skater. Several dimensions, ratios and Heath-Carter somatotypes were derived. Test skaters are heavier and generally larger than pre-elite skaters. Test stream skaters also have larger limb circumferences, estimated calf and arm musculature, and a thicker sum of skinfolds, and are more endomorphic than pre-elite skaters. Elite skaters are more mesomorphic than pre-elite skaters. The sitting height/stature (SH/ST) ratio is significantly lower in pre-elite skaters, while elite and test stream skaters do not differ in this indicator of proportions. Free skaters are taller and heavier; have a higher body mass index (BMI), limb circumferences and sum of skinfolds; and proportionally shorter legs than dancers and pair skaters. Free skaters, dancers and pair skaters, however, do not differ in somatotype. The results suggest that figure skating favors lightness, leanness, higher mesomorphy and lower endomorphy at more elite levels. Shortness, leanness and linearity of physique appear to be selective factors associated with specialization in dance and pair skating.
 
—Relationship between performance times in each trial (A) and Bland-Altman plots (B). Top to bottom; T1 vs. T2, T1 vs. T3 and T2 vs. T3). Dotted lines represent limits of agreement (±1.96 SDs; 95% confidence) and solid line is mean bias between trials.  
Aim: This study investigated the familiarisation to and test re-test reproducibility of constant load cycling at 110% peak power output (WPEAK). Methods: Eleven healthy, but not cycle trained, males performed a graded incremental exercise test to ascertain WPEAK followed by three trials (T1, T2 and T3) at 110% WPEAK to exhaustion. Trials were separated by ~7 days. Results: Although there was no difference in time to exhaustion (TLIM) between T1 and T2 (P=0.100) and T2 and T3 (P=0.095) respectively, a difference was observed between T1 and T3 (P=0.046). Correlation coefficients, coefficients of determination, limits of agreement (LoA) and within-subject coefficient of variation (CV) improved across trials demonstrating T2 and T3 had the strongest relationship (T1 vs. T3: r=0.73; r2=0.53; Bias=40 s; CV=14%; T1 vs. T2: r=0.66; r2=0.43; Bias=24 s; CV=10%; T2 vs. T3: r=0.97; r2=0.95; Bias=16 s; CV=7%). There was no difference across trials for HR (P=0.12), BLa (P=0.76), RER (P=0.52), VE, (P=0.32), VO2, (P=0.33), local RPE (RPEL; P=1) and overall RPE (RPEO; P=0.91) at exhaustion or BLa (P=0.76) and pH (P=0.47) 5-minutes post-exercise. Conclusion: Constant load cycling at 110% WPEAK is a reliable protocol when assessing supramaximal exercise performance after completion of two familiarisation trials.
 
As a part of a larger study, a physical fitness battery was administered to over 6,000 Belgian boys, aged 6 to 13. The coefficients of variation of each of the physical fitness parameters are compared at each age level. The data generally showed a decline in the magnitude of the coefficients of variation from 6 to 12 yr of age, and a sharp increase after.
 
Effects of eight weeks of continuous and interval running on maximum aerobic and anaerobic power were assessed comparatively in 68 female Nigerian schoolgirls aged 15.5 years. The subjects were categorised into a control group (n = 23), a continuous jogging (n = 22), and an interval jogging (n = 23) groups. Standardized field tests were used to measure the subjects' aerobic and anaerobic capacities within one week before and one week after the study. Statistical analysis included one-way analysis of variance and Newman-Keuls post hoc method. Continuous running involved jogging 4.8 km three times a week for eight weeks at subjects' 80 to 85% maximum heart rate (HRmax). Interval running consisted of jogging four 240-second sets interspersed with four minutes of relief interval three times a week for eight weeks. This amounted to a work-to-relief ratio of 1:1. The interval jogging was performed at about 90% of the subjects' HRmax. In contrast to the control group, both exercise groups had comparable magnitude of significant improvements in their aerobic and anaerobic power (p < 0.01). In general, improvements in aerobic power of 1.6%, 10.2%, and 11.5% as well as gains in anaerobic power of 2.4%, 13.2% and 14.6% were found in the control group, continuous running and interval jogging categories, respectively. Both continuous and interval training programmes are effective in altering aerobic and anaerobic power scores in sedentary female adolescents.
 
The purpose of this study was to investigate the physical qualities of junior rugby league players (Under 14, 16, and 18) and determine if preseason fitness measures were significantly different for the players selected to play in the first competitive game of the season (i.e. starters) compared to the players not selected (i.e. non-starters). Eighty-eight junior (N.=53 Under 14; N.=20 Under 16; N.=15 Under 18) subelite rugby league players participated in this study. All players were registered with the same junior recreational rugby league club. Subjects underwent measurements of anthropometry (height, body mass, and sum of four skinfolds), speed (10-m, 20-m, and 40-m sprint), change of direction speed (505 test), estimated lower body power (vertical jump), and estimated maximal aerobic power (multi-stage fitness test) at the beginning of the competitive season. While the relative importance of the different physical qualities differed between playing levels, starters tended to be taller, have faster change of direction speed, and greater playing experience than non-starters. Moderate to large effect size differences were detected between starters and non-starters for speed and estimated maximal aerobic power results. These findings demonstrate that junior rugby league players selected to the starting team have better developed physical qualities than non-starting players. Coaches should emphasise the development of speed, change of direction speed, and aerobic qualities in junior rugby league players.
 
This study assessed comparatively the effects of eight weeks of continuous and interval jogging on percent body fat and blood pressure in 55 untrained Nigerian schoolboys whose mean age was 16 years. The subjects were categorised into a control group (n = 18), a continuous running group (n = 18), and an interval running group (n = 19). Relative body fat was determined with age-specific regression equations using Lange skinfold calipers. Resting blood pressure was measured as recommended by the American Heart Association. Subjects' pre- and post-training percent body fat and resting blood pressure measurements were determined within one week of the beginning and one week after the end of the training programme. Subjects within the continuous running group jogged 4.8 km, three times a week for eight weeks at 80-85% of their maximum heart rate (HRmax). The interval group jogged four 240-second intervals three times a week for eight weeks at 90-95% of their HRmax. Four minutes of walking were allowed between work intervals amounting to a 1:1 work-to-relief ratio. A ten-second post-exercise heart rate and the caloric expenditure per workout were used to ascertain the intensity of the exercise programmes. The control group had no exercise regimens. Statistical analysis included one-way analysis of variance, Newman-Keuls post hoc analysis and Pearson's correlation analysis. In contrast to the control group, the exercise groups had significantly reduced percent body fat (p < 0.05). Relative body fat was reduced by 1.5%. 8.1%, and 7.2% in the control group and continuous and, interval jogging groups, respectively. Conversely, non-significant decreases in systolic and diastolic blood pressure levels were noted in all the different categories of subjects. Non-significant positive association was also found between relative body fat and blood pressure in the groups. Thus, continuous and intermittent jogging programmes are not superior to each other in affecting the levels of percent body fat and blood pressure in male adolescents.
 
The influence of maturity status on body size, functional capacities and basketball-specific skills was evaluated and multivariate relationships between domains of variables were examined in 80 male basketball players 12.0-13.9 years. Height, body mass and two skinfolds were measured. Stage of pubic hair (PH) was assessed clinically. Functional capacity was assessed with the vertical jump (squat jump, countermovement jump), 2-kg medicine ball throw, hand grip strength, 60-second sit-ups and endurance shuttle run. Performances on four basketball skills were tested: shooting, passing, dribbling and defensive movements. Analysis of covariance with age as the covariate was used to test differences among players by stage of puberty. Associations among body size, adiposity, functional capacities and skills were evaluated with canonical correlation analysis. Maturity status explained a significant portion of variance in body size (F=50.13, P<0.01, h2=057, for height; F=13.47, P<0.01, h2=0.26, for weight). The effect of pubertal status was significant for the jumps and upper limb strength, but not for sit-ups or aerobic endurance. Canonical correlations showed an inverse relationship of height and adiposity with skill tests, and a positive relationship between skills and a combination of abdominal muscular strength (sit-ups) and aerobic endurance. Skill appeared to be independent of pubertal status and the tallest group of basketball players did not attain better scores in basketball-specific skill tests.
 
The effects of 2 extra lessons per week in physical education during a school year upon the physical development of school boys (n=70) with chronological age of 12.5 (±0.4) yr were investigated. In a pretest posttest control group design anthropometric, physiologic and gymnologic characteristics were measured. The mean difference scores of experimental and control groups were compared by way of analysis of covariance while making allowance for the influence of biological age and habitual physical activity. Many hypotheses were tested; only achievement in physical education and performance in handgrip increased significantly.
 
Eighteen young adult males were placed into either the control or the experimental group. The subjects of the experimental group were required to undergo a daily physical training regimen and lose a minimum of 4% body weight in six weeks. This study took place at 1310 m altitude. Both groups were tested before and after the six weeks on body weight, elbow flexion strength, knee extension strength, RBC, Hb, and Hct. Results indicated that as a consequence of the physical training program, weight was lost (p<0.05), elbow flexion strength improved (p<0.05), knee extension strength increased (p<0.05) and all blood parameters increased (RBC (p<0.05), Hb (p>0.05), Hct (p<0.05).
 
The aims of this study were: a) to describe the anthropometric characteristics and technical skills in children aged 12 and 14 taking part in competitive basketball; b) to compare the mean scores between these two groups; and c) to detect the relationship between anthropometric characteristics and basketball skills. At the sample of total of 118 young basketball players, 54 of 14 (± 0.5) year old and 64 of 12 (± 0.5) year old, 18 anthropometric variables were measured: five longitudinal measures, two transversal measures, body mass, four circumferences, six skinfolds and 3 derived variables: Body Mass Index (BMI), sitting height/stature ratio (SH/ST ratio) and sum of skinfolds (SUM SKF). Also, they did four basketball field tests: speed spot shooting, passing, control dribble and defensive movement. Values of most of anthropometric variables were significantly higher in 14 year old players as compared to 12 year old, except in SH/ST ratio and BMI which were similar. Only values of SUM SKF were significantly lower in 14 year old players. In variables: control dribble, passing and defensive movement 14 year old players have better scores then 12 year old players. The players presented a very high values of anthropometric dimensions, especially longitudinal and a very good technical skills. The correlation between certain field tests and some anthropometric parameters indicates that some anthropometric measures might have moderately negative influence on test results in technical skills in 14 year old players.
 
Twenty male Puerto Rican basketball players participated in a 14-week season of practice and competition. An assessment of body composition and physiological response to submaximal and maximal work was made prior to training (T1), after four weeks of practice (T2) and following 10-weeks of practice and competition (T3). Results show a significant decrease in percent body fat, standardized submaximal work loads. During maximal work, absolute values of oxygen consumption (liters/min) increased slightly and relative max vO2 (ml/kgxmin) improved 7.7%, manly due to a decrease in body weight. It was concluded that basketball training, despite the high energy cost during competition, does not favorably modify the functional capacity of the cardiovascular system, but does result in some desirable modifications in body composition and cardiovascular efficiency during submaximal work.
 
The aims of this study were to use the Maximal Aerobic Speed (MAS) to set training intensities for aerobic training and to measure the effects of two different training programmes on MAS and on the running time to exhaustion at 100% of MAS (Tlim) for 121 students aged 14 to 17 years. The MAS was measured using the Université de Montréal Track Test (UMTT). This measurement was found reproducible for males (r = 0.93) and females (r = 0.68). The Students followed a 12-week training programme of one weekly training session. The MAS and the Tlim were measured the weeks before and after training. Two training programmes were proposed (intense training programme and moderate training programme). These training programmes differed by the ratio between continuous exercises (85% of MAS) and intermittent exercise (between 90% and 120% of MAS). For the moderate training programme, the ratio between continuous and intermittent exercises was greater than for the intensive training programme. Twenty subjects served as control group. The students MAS and Tlim (mean +/- SD) were respectively 13.7 +/- 1.6 km.h-1 and 380.5 +/- 91.8 s for the males and 11.3 +/- 1.2 km.h-1 and 347.2 +/- 91.1 s for the females. Our results indicated that only the subjects of the intense training group improved their MAS: + 5.7% for the males (p < 0.001) and + 5.4% for the females (p < 0.001). In neither case was Tlim significantly improved with training. In conclusion, we can notice that MAS is a pertinent criterion to set training intensities for aerobic training and that a weekly training session over 12 weeks is sufficient to moderately improve the MAS of initially untrained students.
 
Pubertal changes constitute a background for development of motor abilities and flexibility as an important component of physical fitness. The aim of the present study was to investigate whether the flexibility is actually related to sexual maturation stages in adolescent boys. This cross-sectional study was conducted on 69 healthy boys aged 14 years. Before testing, all participants performed a 3 min warm up and static stretch routine, emphasizing the lower body. The flexibility tests were performed in a counterbalanced design. Sit-and-reach test and goniometric measurement of hamstring flexibility was administered. The results of flexibility tests and body measures were analysed for cross-sectional comparison. Groups were formed according to Tanner's classification and consisted of boys in Stage II, III, IV, V, respectively. The results of sit and reach test scores and goniometric measurements did not correlate with age in months, height, weight and BMI; and furthermore they did not correlate with the sexual maturation stages (p>0.05). The sit and reach test scores were significantly correlated with goniometric measurements (right: r=0.653, p=0.00; left: r=0.638, p=0.00). The results suggest that sexual maturation stages in pubertal period would not be effective in determining the flexibility. Besides, sexual maturation is not a cause of decreased flexibility in adolescent boys aged 14 years.
 
Systolic and diastolic blood pressures were studied for 14 weeks using trained male joggers aged 32-47 years who were part of a conditioning program. The blood pressures of the 13 subjects were recorded in late afternoon prior to jogging (operational blood pressures), immediately after jogging, and after a 5-minute walk to cool down. Analyses of variance revealed significant differences among the 14 weekly systolic measures that were taken prior to exercise. Similar differences were found among the systolic measures taken after the 5-minute recovery period. Duncan's Multiple Range Test revealed 16 significant mean differences for pre-exercise systolic blood pressure and 18 significant mean differences for 5-minute recovery systolic blood pressure. Trend analyses computed for both pre-exercise and 5-minute walk recovery blood pressures over the 14 weeks revealed significant linear components for both dependent variables. The study revealed that operational systolic blood pressure can be decreased as a result of jogging.
 
One hundred forty-six professional football players from one NFL team were exercise stress tested prior to the start of the regular season using a modified Bruce treadmill protocol. Electrocardiographic study at rest, exercise, and recovery showed abnormalities such as left ventricular hypertrophy, early repolarization variant, sinus bradycardia, and others. These findings were considered to be normal variants for athletic populations. Echocardiographic follow-up in selected subjects who manifested specific auscultative symptoms in screening, showed mitral valve prolapse, left ventricular enlargement, and possible atrial septal defect. Cardiovascular response to exercise resulted in somewhat lower maximum heart rates and higher estimated VAEO2max values than those reported in the literature.
 
A 33 item multiple choice questionnaire was circulated; completed questionnaires from 1505 runners (1130 male and 375 female) were obtained. Questions focused upon training, injuries sustained, and medical care. Biomechanical imbalances such as leg length inequality appear to be a major contributing factor to running injuries. Correction of an underlying biomechanical defect may be important in the treatment of many running injuries. Female runners were found to be more susceptible than males to stress fractures at higher mileages. The cause of this increased incidence may be attributable to lower bone mineral density levels as a result of hormonal factors. Factors such as running surface, age and stretching techniques do not appear to play a significant part in the pathogenesis of running injuries.
 
The physiological and clinical importance of body composition is part of public health, nutrition and Sports medicine. The most popular field method for estimating total body adiposity remains anthropometry separately or in formulae. The aim of this study was to verify the suitability of an absolute maximum out of more than 600 existing anthropometry equations estimating % adipose tissue (AT) in a cross validation with dual energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA) and hydrodensitometry (HD) on 74 British male subjects (mean age 34.4±14.1) with different lifestyles corresponding to a maximum of populations the original formula was developed for. Pearson correlation coefficients, paired sample t-test and Bland and Altman plots where used for analyses. From the tested formulae, 19 correlated well (r≥0.70) and showed no significant difference (p>0.05) with BIA, 15 with DXA and only 12 with HD. The results show a better match of the predicted % AT by anthropometric equations with BIA then with DXA or HD. All results and conditions considered, this study suggest not to use HD nor anthropometric formulae to assess % AT in men for an individual estimation.
 
The aim of this study was to determine the effect of an upper-arm muscle weight training (WT) protocol over 16 weeks on bone density at the proximal phalanges in young healthy men. Fifty-one healthy volunteer men were selected, 16 for an experimental group and 35 for a control group. The experimental group was submitted to the prescribed WT protocol to develop the strength of upper arm muscles, during 16 weeks, at a frequency of 3 times per week for approximately 60 min per session. Anthropometric data (weight, height, body mass index, corrected mid upper-arm circumference [cMUAC], and percentage of upper-arm muscle mass [%UAMM]) and bone density by quantitative ultrasound (DBM Sonic BP, IGEA, Italy) at proximal phalanges (amplitude dependent speed of sound [AD-SoS], T-score, %T-score) were evaluated on non-dominant limb before the beginning of the study (T0) and after 16 weeks (T1). There were no significant differences among all variables at T0 and T1 in the control group, nor at T0 between both groups. In the experimental group, cMUAC, %UAMM, AD-SoS, T-score and %T-score were significantly higher at T1 in relation to T0, as well as between T1 of the experimental group and T1 of the control group (all with P<0.0001). The gain of %T-score showed a correlation between cMUAC gain (P=0.005) and %UAMM gain (P=0.002). The experimental group showed 7% of bone mass gain. These data suggested that a WT protocol to develop strength of upper arm muscles over 16 weeks was effective for increasing bone density at the proximal phalanges in healthy young men.
 
Aim: The aim of this study was to compare the morphology and physical fitness of 104 under-16 male handball athletes with different competitive levels in function of their bone maturation. Methods: Athletes were divided into two groups, 59 competed in the NL-national league, with higher competitive level (14.06±0.66 years) and 45 competed in the RL-regional league (14.24±0.60 years). The morphology was evaluated by measuring body mass, height, sitting height, arm span, four lengths, four breadths, five girths and eleven skinfolds. The physical fitness assessment used eight tests (20-m shuttle run; 30-m sprint; sit-and-reach; horizontal and vertical jump with counter movement; overhead medicine ball throw-3 kg; handgrip; handball specific agility test). Bone age was determined using the TW3 method. Results: In morphological terms, NL athletes showed greater dimensions for all anthropometric variables except for hand length (transversal and longitudinal), biepicondylar femur breadth, mid-thigh girth and skinfolds. In physical fitness terms, these athletes have better results for VO2max, velocity, agility, arm strength and handgrip than athletes competing in the RL. Maturational differences explain the morphological profile superiority of NL athletes in terms of arm span, lower limb length, biacromial breadth and physical fitness profile for VO2max and arm strength. Conclusion: Maturation should be considered as a covariate when one intends to distinguish the morphological characteristics and physical fitness of under-16 athletes with different levels of practice.
 
Coordinative abilities play a very important role in sport. Unfortunately, researchers do not confine appropriate attention to this issue. Therefore, the aim of this study was an attempt at analysing results of the selected coordinative motor abilities: kinaesthetic differentiation, quick reaction and spatial orientation. It was intended to find out whether the results of trials determining manifestations of the particular coordinative abilities exhibit any mutual relationships. Forasmuch as a static torque is a parameter determining the level of force components of the ability of kinaesthetic differentiation, it would like to find out whether its maximum level influences the final result. Research was carried out on 20 young basketball players with the use of a torque meter and Fusion Smart Speed System. It was noticed a lack of statistically significant relationships between the results of trials assessing manifestations of the ability of kinaesthetic differentiation, quick reaction and spatial orientation. However, it was noted statistically significant correlation between the maximum static torque and the accuracy of releasing a particular value of a static torque. The accuracy of releasing a particular value of a static torque ought to be classified as a comprehensive ability that comprises manifestations of strength abilities and kinaesthetic differentiation. Presented trials to evaluation manifestations of the selected coordinative abilities could be used by coaches during a training process. Coaches should also focus on the development of muscle strength of the upper body and upper limbs of basketball players.
 
The relationship between salivary IgA secretion rate and upper respiratory tract infection (URTI) was studied in 155 ultramarathoners (126 males, 29 females, mean age 46.5+/-0.7 y) who had qualified to run the 160-km 2003 Western States Endurance Run. Subjects provided saliva samples during registration, held the morning before the race, and within 5-10 minutes postrace (mean race time, 26.2+/-0.3 h). Unstimulated saliva was collected by expectoration for 4 minutes into 15-mL plastic, sterilized vials. Runners finishing the race and providing pre- and postrace saliva samples (n=106) turned in a health log specifying URTI episodes and severity of symptoms for the 2-week period following the race. The total volume of saliva that the runners was able to expectorate during sample collection decreased 51% postrace compared to prerace values (P<0.001). Saliva protein concentration increased 20% (P<0.001) while the saliva protein IgA concentration decreased 10% (P<0.05). Salivary IgA secretion rate decreased 46% when comparing pre- to postrace values (P<0.001). Twenty-four percent of the runners finishing the race and providing salivary samples reported an URTI episode lasting 2 days or longer during the 2-week period following the race (mean number of days with symptoms was 5.4+/-0.6 days). The decrease in salivary IgA secretion rate (pre- to postrace) was 53% greater in the 25 runners reporting URTI (-355+/-45 microg/min) compared to the 81 runners not reporting URTI (-232+/-37 microg/min), (P=0.04). In summary, nearly 1 in 4 runners reported an URTI episode during the 2-week period following a 160-km race, and the decrease in salivary IgA secretion rate was significantly greater in these runners compared to those not reporting URTI.
 
The object of this study was to verify the validity of specific parameters of cardiorespiratory endurance and anthropometric measurements that exist among the young on a run of 1600 meters for 10-12 years old, and 2400 meters for 13-17 years old children. The sample was randomly selected and was comprised of 159 boys and 162 girls, aged 10-17 years old. The endurance test was performed on an external surface of 50 m x 50 m, and the subjects were encouraged to complete the predetermined distance, as quickly as possible. During the 3 days prior to or following the tests on the courses, the V̇O2max was measured while the subjects performed a maximum workload on the bicycle ergometer by the direct method using the open system to analyse the expired gases (Beckman MMC). The correlations between the time to complete the run and the V̇O2 max varied from 0.62 and 0.84 for the different age and sex groups. The correlations were similar for both sexes for the 1600 meters, while the value was higher for the girls on the 2400 meter distance. Several regression equations were calculated to predict the V̇O2 max from the running time, the average speed, the weight, the height, and the sum of the skinfold thickness. The most significant anthropometric variable (r=-0.418) was that of body weight. The most practical and adequate equation to apply to both sexes for the two distances was: V̇O2max (ml.kg⁻¹.min⁻¹)=22.5903+12.2944 (speed, m/sec)-0.1577 (weight, kg), in which r=0.804 and SEE=5.54. The average error of prediction was 10% for the boys and 13% for the girls.
 
Although the relationships among body composition, training, and physical characteristics and 17 B-estradiol (estradiol) have been described in active amenorrheic women, little is known about these relationships in eumenorrheic women. This study examined the relationship between selected body composition and training variables, physical characteristics, maximal oxygen consumption (VO2max), luteinizing hormone (LH) and estradiol in eumenorrheic runners. Fifteen women (25.8 +/- 0.8 years) running 19.8 +/- 1.8 miles per week were studied during the midluteal phase of the menstrual cycle. Estradiol and LH were determined by radioimmunoassay. Body composition was measured by hydrostatic weighing. Age, Ponderal Index, and menstrual cycle length (days) were inversely related to estradiol (r = -0.56, r = -0.55, r = -0.52, respectively, p less than 0.05). A significant relationship (R2 = 0.91; p less than 0.05) was found among age, menstrual cycle length, LH (mIU/ml), VO2max (ml/kg/min), weight training (hr/wk), miles run per week, height (cm), additional aerobic training (hr/wk), relative body fat (%), and Ponderal Index and estradiol (pg/ml). These data suggest the midluteal concentration of estradiol in moderately trained eumenorrheic runners is the result of a complex interaction of many factors.
 
The urinary excretion of catecholamines and 17 hydroxycorticosteroids (OHCS) of 15 young, healthy, volunteer male students was measured before and after two phase, submaximal work on a bicycle ergometer. After the work, the excretion of noradrenaline and adrenaline was about doubled (p<0.001). The ratio of the excretion of noradrenaline to that of adrenaline did not alter significantly. The excretion of 17 OHCS increased statistically significantly (p<0.02).
 
Exercise tests evaluate the effects of physical activity, which is one of the four recommendations for diabetes treatment. An adjusted and accurate measure of aerobic capacity in diabetic patients is thus needed. This study compared two estimates of aerobic fitness (maximal oxygen uptake vs physical working activity PWC170, i.e., the workload at a pulse of 170) and the usual versus a reduced insulin dose in preadolescent boys with type 1 diabetes mellitus. Sixteen prepubertal type 1 diabetic boys performed a submaximal test, the PWC(170). Gas exchange values and capillary blood glucose levels were monitored and, when possible, the test was extended to exhaustion. In 7 boys, the test was performed twice on separate days. On one day they received their usual insulin dose and on the other, their short-acting insulin was reduced by 1/3; the two tests were held in random order. The 9 other children were tested only once after receiving their usual insulin dose. For the 16 boys who performed the test with the usual insulin dose, PWC(170) (W) and peak oxygen uptake (peak VO(2)) (L.min(-1)) correlated closely (r=0.81, P=0.002). Aerobic fitness did not change with insulin dose, but some hypoglycemic episodes occurred when insulin dose was not reduced. Since maximal effort does not add more information, routine use of the submaximal peak VO(2)-correlated test, the PWC(170), seems sufficient, possibly in association with a planned insulin dose reduction. This dose change does not interfere with performance, but could reduce the risk of hypoglycemia.
 
-The IL6 −174 G/C genotype and allele frequencies in all groups. 
Aim: Interleukin-6 (IL6), has been called by some authors "an exercise factor" due to its pleiotropic effects during physical training. Several studies indicated that change in the guanine bases to cytosine at position -174 affects the transcription of the IL6 gene, and finally IL6 production level. The aim of this study was to perform confirmation studies to analyze the possible importance of the IL6 -174 G/C (rs1800795) polymorphism gene in Polish power-orientated athletes. Methods: The study was carried out on two groups of men of the same Caucasian descent: 158 power-orientated athletes and 254 volunteers not involved in competitive sport. DNA was extracted from buccal cells donated by the subjects. Genotyping was carried out by polymerase chain reaction (PCR). Significance was assessed by Chi square (χ2) analysis. Results: The results revealed that the frequency of the IL6 -174 GG genotype (53.16% vs. 35.82%; P=0.002) and G allele (68.67% vs. 57.87%; P=0.03) were significantly higher in the Polish power-orientated athletes compared to controls. Conclusion: These data suggest that the G allele could be one of the factors influencing the power-orientated sport performance. However, these conclusions should be supported with more experimental studies on other IL6 polymorphisms and other genes.
 
The aim of this paper was to investigate the prevalence and sports distribution in athletes. Six hundred and fifty radiographs of athletes affected by tenderness and exertional pain in the region of the Achilles tendon, were observed over a period of 30 years. The clinical and diagnostic imaging materials were reviewed. Eighteen cases of accessory symptomatic soleus muscle were diagnosed: in 10 cases using soft tissue radiographic technique, in 8 cases using, in sequence, exclusively ultrasound and magnetic resonance. The presence of an accessory soleus muscle has been considered a rare even incidental occurrence; the review of our cases, substantially different for the evident symptoms, showed a frequency in athletes of 2.77% in accordance with the results of the anatomical and clinical literature. US and MRI are the best diagnostic modalities especially in differentiating accessory soleus muscle from soft tissue tumors not rare in this anatomic region.
 
Top-cited authors
Jan Chmura
  • Akademia Wychowania Fizycznego we Wrocławiu
Pawel Chmura
  • Wrocław University of Health and Sport Sciences
Filipe Manuel Clemente
  • Instituto Politécnico de Viana do Castelo
Dihogo Matos
  • University of Manitoba
Victor Machado Reis
  • Universidade de Trás-os-Montes e Alto Douro