Objectives: To define physiological upper limits of left ventricular (LV) cavity size in trained adolescent athletes.
Design: Cross sectional echocardiographic study.
Setting: British national sports training grounds and Olympic Medical Institute.
Subjects: 900 elite adolescent athletes (77% boys) aged 15.7 (1.2) years participating in ball, racket, and endurance sports and 250 healthy controls matched for age, sex, and size.
Main outcome measures: LV end diastolic cavity size.
Results: Compared with controls, athletes had a larger LV cavity (50.8 (3.7) v 47.9 (3.5) mm), a difference of 6%. The LV cavity was > 54 mm in 18% athletes, whereas none of the controls had an LV cavity > 54 mm. The LV cavity exceeded predicted sizes in 117 (13%) athletes. Among the athletes with LV dilatation, 78% were boys, LV size ranged from 52–60 mm, and left atrial diameter and LV wall thickness were enlarged. Systolic and diastolic function were normal. None of the athletes in the study had an LV cavity size > 60 mm. LV cavity size correlated with age, sex, heart rate, and body surface area.
Conclusion: Highly trained junior athletes usually have only modest increases in LV cavity size. A proportion of trained adolescent athletes have LV cavity size exceeding predicted values but, in absolute terms, LV cavity rarely exceeds 60 mm as in patients with dilated cardiomyopathy. In highly trained adolescent athletes with an LV cavity size > 60 mm and any impairment of systolic or diastolic function, the diagnosis of dilated cardiomyopathy should be considered.
adolescent; elite athlete; athlete’s heart; cardiomyopathy; ventricular cavity dilatation
Background & objectives:
Intensive regular physical exercise training is associated with a physiological changes in left ventricular (LV) morphology and functions. This cardiac remodeling observed in the athletes is associated with the specific haemodynamic requirements of the exercise undertaken. The main objective of this study is to evaluate the effect of endurance training on cardiac morphology, systolic and diastolic LV functions and haemodynamic parameters both in male and female athletes.
Seventy nine healthy athletes (age 20.0 ± 2.6 yr; 49% male) and 82 healthy sedentary adolescent (age 20.8 ± 2.2 yr, 49% male) volunteered to participate in this study. All subjects underwent transthoracic echocardiography and impedance cardiography.
Both female and male athletes had greater LV end-diastolic cavity sizes, LV mass and stroke volume (SV) values when compared with controls. Also, in male athletes, LV mass index was higher than in female athletes. While male athletes had lower resting heart rate compared to female athletes, they had higher mean arterial blood pressure. In male athletes, basal septal and mid septal strain values were higher compared to controls. There were no significant differences in strain and peak systolic strain rate values between female athletes and controls. In male athletes, there was a weak positive correlation between SV and LV mass, basal lateral and septal strain values. In female athletes, only a weak positive correlation was found between SV and basal septal strain values.
Interpretation & conclusions:
Endurance-trained male and female athletes had higher LV mass, LV cavity dimensions and SV compared to sedentary controls. Although there was no difference in diastolic cardiac functions between athletes and controls, local enhanced systolic function was found with increase of SV. Both morphologic and haemodynamic differences were more evident in male athletes.
Athlete's heart; endurance training; impedance cardiography; strain imaging; tissue Doppler
We investigated the response of insulin-like growth factor (IGF- I), insulin-like growth factor binding protein-3 (IGFBP-3) and some hormones, i.e., testosterone (T), growth hormone (GH), cortisol (C), and insulin (I), to maximal exercise in road cyclists with and without diagnosed left ventricular hypertrophy. M-mode and two-dimensional Doppler echocardiography was performed in 30 professional male endurance athletes and a group of 14 healthy untrained subjects using a Hewlett-Packard Image Point HX ultrasound system with standard imaging transducers. Echocardiography and an incremental physical exercise test were performed during the competitive season. Venous blood samples were drawn before and immediately after the maximal cycling exercise test for determination of somatomedin and hormonal concentrations. The basal concentration of IGF-I was statistically higher (p < 0.05) in athletes with left ventricular muscle hypertrophy (LVH) when compared to athletes with a normal upper limit of the left ventricular wall (LVN) (p < 0.05) and to the control group (CG) (p < 0.01). The IGF-I level increased significantly at maximal intensity of incremental exercise in CG (p < 0.01), LVN (p < 0.05) and LVH (p < 0.05) compared to respective values at rest. Long-term endurance training induced an increase in resting (p < 0.01) and post-exercise (p < 0.05) IGF-I/IGFBP-3 ratio in athletes with LVH compared to LVN. The testosterone (T) level was lower in LVH at rest compared to LVN and CG groups (p < 0.05). These results indicate that resting serum IGF-I concentration were higher in trained subjects with LVH compared to athletes without LVH. Serum IGF- I/IGFBP-3 elevation at rest and after exercise might suggest that IGF-I act as a potent stimulant of left ventricular hypertrophy in chronically trained endurance athletes.
Key pointsIn sports training athletes engaged in the same training regimen acquired different stages of cardiac hypertrophy.Physical exercise had a significant effect on serum insulin-like growth factor - I concentration depending on maximal oxygen uptake during endurance exercise.Athletes with clinically diagnosed physiological left ventricular hypertrophy had higher resting serum insulin-like growth factor - I concentration compared to those without left ventricular hypertrophy and sedentary subjects.Increased insulin-like growth factor - I release during long-term training seems to significantly contribute to sports-specific functional adaptation of the left ventricle.
Echocardiography; heart; somatomedins; anabolic hormones; endurance training.
Increased myocardial mass due to regular high-volume intense exercise training (so-called athlete’s heart) is not uncommon. Although directly correlated with the extent of training loads, myocardial hypertrophy is not present exclusively in well-trained or elite athletes. Athlete’s heart is considered a physiological phenomenon with no known harmful consequences. However, extreme forms of myocardial hypertrophy due to endurance training resemble a structural heart disease such as hypertrophic cardiomyopathy, a condition associated with substantially increased risk of cardiac event. Endurance sports such as rowing and road cycling, rather than strength/power training, are most commonly associated with left ventricular (LV) wall thickness compatible with hypertrophic cardiomyopathy. The differentiation between physiological and maladaptive cardiac hypertrophy in athletes is undoubtedly important, since untreated cardiac abnormality often possesses a real threat of premature death due to heart failure during intense physical exertion. Luckily, the distinction from pathological hypertrophy is usually straightforward using transthoracic echocardiography, as endurance athletes, in addition to moderately and proportionally thickened LV walls with normal acoustic density, tend to possess increased LV diameter. In more uncertain cases, a detailed evaluation of myocardial function using (tissue) Doppler and contrast echocardiography is effective. When a doubt still remains, knowledge of an athlete’s working capacity may be useful in evaluating whether the insidious cardiac pathology is absent. In such cases cardiopulmonary exercise testing typically resolves the dilemma: indices of aerobic capacity are markedly higher in healthy endurance athletes compared to patients. Other characteristics such as a decrease of LV mass due to training cessation are also discussed in the article.
Key pointsTransthoracic echocardiography is still the most common relevant differentiation technique applied to distinguish athlete’s heart from the cardiomyopathy.Conventional echocardiographic criteria such as left ventricular chamber size and diastolic function parameters are to be regarded first when making differential diagnosis between substantially increased wall thickness in athlete’s heart (i.e. physiological adaptation) versus a disease (usually hypertrophic cardiomyopathy).When conventional echocardiographic parameters fail to diagnose the nature of myocardial hypertrophy, other differentiation criteria such as aerobic fitness, cardiac performance in response to physical exertion, and changes in echocardiographic parameters due to detraining, must be taken into consideration.Tissue Doppler, contrast and three-dimensional imaging are state-of-the-art echocardiographic techniques which have recently appeared in the differential diagnostics.
Left ventricle; physical exercises; physiological adaptation
BACKGROUND--Clinical distinction between athlete's heart and hypertrophic cardiomyopathy in a trained athlete is often difficult. In an effort to identify variables that may aid in this differential diagnosis, the effects of deconditioning on left ventricular wall thickness were assessed in six highly trained elite athletes who had competed in rowing or canoeing at the 1988 Seoul Olympic Games. Each of these athletes showed substantial ventricular septal thickening associated with training (13-15 mm) which resembled that of hypertrophic cardiomyopathy. METHODS--The athletes voluntarily reduced their training substantially for 6-34 weeks (mean 13) after the Olympic competition. Echocardiography was performed at peak training and also after deconditioning, and cardiac dimensions were assessed blindly. RESULTS--Maximum ventricular septal thickness was 13.8 (0.9) mm in the trained state and 10.5 (0.5) in the deconditioned state (p < 0.005) (change 15-33%). CONCLUSIONS--The finding that deconditioning may be associated with a considerable reduction in ventricular septal thickness in elite athletes over short periods strongly suggests that these athletes had a physiological form of left ventricular hypertrophy induced by training. Such a reduction in wall thickness with deconditioning may help to distinguish between the physiological hypertrophy of athlete's heart and primary pathological hypertrophy (for example, hypertrophic cardiomyopathy) in selected athletes with increased left ventricular wall thickness.
Differentiating physiological cardiac hypertrophy from pathology is challenging when the athlete presents with extreme anthropometry. While upper normal limits exist for maximal left ventricular (LV) wall thickness (14 mm) and LV internal diameter in diastole (LVIDd, 65 mm), it is unknown if these limits are applicable to athletes with a body surface area (BSA) >2.3 m2.
To investigate cardiac structure in professional male athletes with a BSA>2.3 m2, and to assess the validity of established upper normal limits for physiological cardiac hypertrophy.
836 asymptomatic athletes without a family history of sudden death underwent ECG and echocardiographic screening. Athletes were grouped according to BSA (Group 1, BSA>2.3 m2, n=100; Group 2, 2–2.29 m2, n=244; Group 3, <1.99 m2, n=492).
There was strong linear relationship between BSA and LV dimensions; yet no athlete with a normal ECG presented a maximal wall thickness and LVIDd greater than 13 and 65 mm, respectively. In Group 3 athletes, Black African ethnicity was associated with larger cardiac dimensions than either Caucasian or West Asian ethnicity. Three athletes were diagnosed with a cardiomyopathy (0.4% prevalence); with two athletes presenting a maximal wall thickness >13 mm, but in combination with an abnormal ECG suspicious of an inherited cardiac disease.
Regardless of extreme anthropometry, established upper limits for physiological cardiac hypertrophy of 14 mm for maximal wall thickness and 65 mm for LVIDd are clinically appropriate for all athletes. However, the abnormal ECG is key to diagnosis and guides follow-up, particularly when cardiac dimensions are within accepted limits.
This paper reviews studies of supplement use among child and adolescent athletes, focusing on prevalence and type of supplement use, as well as gender comparisons. Supplement use among adult athletes has been well documented however there are a limited number of studies investigating supplement use by child and adolescent athletes. A trend in the current literature revealed that the most frequently used supplements are in the form of vitamin and minerals. While health and illness prevention are the main reasons for taking supplements, enhanced athletic performance was also reported as a strong motivating factor. Generally, females are found to use supplements more frequently and are associated with reasons of health, recovery, and replacing an inadequate diet. Males are more likely to report taking supplements for enhanced performance. Both genders equally rated increased energy as another reason for engaging in supplement use. Many dietary supplements are highly accessible to young athletes and they are particularly vulnerable to pressures from the media and the prospect of playing sport at increasingly elite levels. Future research should provide more direct evidence regarding any physiological side effects of taking supplements, as well as the exact vitamin and mineral requirements for child and adolescent athletes. Increased education for young athletes regarding supplement use, parents and coaches should to be targeted to help the athletes make the appropriate choices.
Key pointsSupplement use among the child and adolescent athlete population is widespread with the most frequently used supplement being a form of vitamin/mineral supplement.The effects of supplement use on the growth and development of children and adolescents remain unclear and thus use of supplements by this population should be discouraged.It is likely that there is a misunderstanding as to the role of vitamins and minerals in the diet, their function in maintaining overall health, their role in athletic performance, and how they are best obtained from the diet therefore further education for adolescent athletes and athletes in general is needed.
Nutrition; sport; adolescent athletes; dietary supplement
The purpose of this study was to examine exercise-induced arterial adaptations in elite Judo male and female athletes. 27 male Judo athletes (age 24.06 ± 2 years), 11 female Judoka (age 24.27 ± 1 years), 27 sedentary healthy men (age 24.01 ± 2 years) and 11 women (age 24.21 ± 1 years) participated in the current study. The examined vessels included brachial, radial, ulnar, popliteal, anterior and posterior tibial arteries. The experimental parameters were recorded with the use of Duplex ultrasound at rest. Diastolic diameter and blood mean flow velocity of the examined arteries in Judo athletes were found to be both significantly increased (p < 0.05) compared to the findings of the control groups. In male Judo athletes the brachial (p < 0.001), radial (p < 0.001), and anterior tibial artery (p < 0.001) presented the highest difference on the diastolic diameter, compared with the control male group. In female Judo athletes, ulnar (p < 0.001), radial (p < 0.001), and brachial (p < 0.001) arteries illustrated the highest diastolic diameter. The highest blood mean flow velocity was recorded in ulnar (p < 0.001) and popliteal arteries (p < 0.001) of the Judo athletes groups. Recording differences between the two genders, male participants presented larger arteries than females. Conclusively, Judo has been found to be a highly demanding physical sport, involving upper and lower limbs leading to significant arterial adaptations. Obtaining vascular parameters provide a useful tool to the medical team, not only in the direction of enhancement of the efficacy of physical training, but in unknown so far parameters that may influence athletic performance of both male and female elite Judokas.
Key pointsJudo athletes demonstrated a general homogenous increase of the arterial functionality of the upper and lower limbs compared to the control groups.Diastolic diameter found to be significantly increased in male and female Judo athletes, highlighting the effects of exercise training on the vascular system.Judo athletes had had statistically significant increase of the blood mean flow velocity in all examined arteries, compared with the relevant control group.The current study underscores the impact of Judo training on the structure and the function of the arterial system.Clinically, the increased arterial parameters in elite Judo athletes may be essential elements for improved athletic performance.Sports medicine practitioners should give special concern to the vascular functionality for several physiological and medical tests.
Diastolic diameter; blood mean flow velocity; duplex sonography; judo athletes
Background: The effectiveness of cardiovascular screening in minimising the risk of athletic field deaths in master athletes is not known.
Objective: To evaluate the prevalence and clinical significance of ST segment depression during a stress test in asymptomatic apparently healthy elderly athletes.
Methods: A total of 113 male subjects aged over 60 were studied (79 trained and 34 sedentary); 88 of them (62 trained and 26 sedentary) were followed up for four years (mean 2.16 years for athletes, 1.26 years for sedentary subjects), with a resting 12 lead electrocardiogram (ECG), symptom limited exercise ECG on a cycle ergometer, echocardiography, and 24 hour ECG Holter monitoring.
Results: A significant ST segment depression at peak exercise was detected in one athlete at the first evaluation. A further case was seen during the follow up period in a previously "negative" athlete. Both were asymptomatic, and single photon emission tomography and/or stress echocardiography were negative for myocardial ischaemia. The athletes remained symptom-free during the period of the study. One athlete died during the follow up for coronary artery disease: he showed polymorphous ventricular tachycardia during both the exercise test and Holter monitoring, but no significant ST segment depression.
Conclusions: The finding of false positive ST segment depression in elderly athletes, although still not fully understood, may be related to the physiological cardiac remodelling induced by regular training. Thus athletes with exercise induced ST segment depression, with no associated symptoms and/or complex ventricular arrhythmias, and no adverse findings at second level cardiological testing, should be considered free from coronary disease and safe to continue athletic training.
The differentiation between physiological cardiac enlargement and cardiomyopathy is crucial, considering that most young non‐traumatic deaths in sport are due to cardiomyopathy. Currently, there are few data relating to cardiac dimensions in junior elite tennis players. The aim of this study was to define the upper limits of left ventricular dimensions in a large cohort of national adolescent tennis players.
Between 1996 and 2003, 259 adolescent tennis players (152 males), mean (SD) age 14.8 (1.4) years (range 13–19) and 86 healthy age, gender and body surface matched sedentary controls underwent 12‐lead ECG and 2D‐transthoracic echocardiography.
Inter‐ventricular septal end diastolic dimension (IVSd), left ventricular end diastolic dimension (LVEDd) and left ventricular end diastolic posterior wall dimension (LVPWd) in tennis players were significantly higher than in controls (8.9 mm vs 8.3 mm p<0.001, 48.9 mm vs 47.9 mm p<0.05 and 9 mm vs 8.3 mm p<0.001 respectively), however in absolute terms, the difference did not exceed 7%. None of the tennis players had a wall thickness exceeding 12 mm or a left ventricular cavity size exceeding 60 mm.
Tennis players exhibit modest increases in cardiac dimensions, which do not resemble those seen in individuals with cardiomyopathy affecting the left ventricle.
OBJECTIVE—To assess physiological cardiac adaptation in adolescent professional soccer players.
SUBJECTS AND DESIGN—Over a 32 month period 172 teenage soccer players were screened by echocardiography and ECG at a tertiary referral cardiothoracic centre. They were from six professional soccer teams in the north west of England, competing in the English Football League. One was excluded because of an atrial septal defect. The median age of the 171 players assessed was 16.7 years (5th to 95th centile range: 14-19) and median body surface area 1.68 m2 (1.39-2.06 m2).
MAIN OUTCOME MEASURES—Standard echocardiographic measurements were compared with predicted mean, lower, and upper limits in a cohort of normal controls after matching for age and surface area. Univariate regression analysis was used to assess the correlation between echocardiographic variables and the age and surface area of the soccer player cohort. ECG findings were also assessed.
RESULTS—All mean echocardiographic variables were greater than predicted for age and surface area matched controls (p < 0.001). All variables except left ventricular septal and posterior wall thickness showed a modest linear correlation with surface area (r = 0.2 to 0.4, p < 0.001); however, left ventricular mass was the only variable that was significantly correlated with age (r = 0.2, p < 0.01). Only six players (3.5%) had structural anomalies, none of which required further evaluation. All had normal left ventricular systolic function. Sinus bradycardia was found in 65 (39%). The Solokow-Lyon voltage criteria for left ventricular hypertrophy were present in 85 (50%) and the Romhilt-Estes points score (five or more) in 29 (17%). Repolarisation changes were present in 19 (11%), mainly in the inferior leads.
CONCLUSIONS—Chamber dimensions, left ventricular wall thickness and mass, and aortic root size were all greater than predicted for controls after matching for age and surface area. Sinus bradycardia and the ECG criteria for left ventricular hypertrophy were common but there was poor correlation with echocardiographic left ventricular hypertrophy. The type of hypertrophy found reflected the combined endurance and strength based training undertaken.
Keywords: cardiac morphology; professional soccer players; echocardiography; ECG findings
Cardiac remodelling is commonly defined as a physiological or pathological state that may occur after conditions such as myocardial infarction, pressure overload, idiopathic dilated cardiomyopathy or volume overload. When training excessively, the heart develops several myocardial adaptations causing a physiological state of cardiac remodelling. These morphological changes depend on the kind of training and are clinically characterised by modifications in cardiac size and shape due to increased load. Several studies have investigated morphological differences in the athlete’s heart between athletes performing strength training and athletes performing endurance training. Endurance training is associated with an increased cardiac output and volume load on the left and right ventricles, causing the endurance-trained heart to generate a mild to moderate dilatation of the left ventricle combined with a mild to moderate increase in left ventricular wall thickness. Strength training is characterised by an elevation of both systolic and diastolic blood pressure. This pressure overload causes an increase in left ventricular wall thickness. This may or may not be accompanied by a slight raise in the left ventricular volume. However, the development of an endurancetrained heart and a strength-trained heart should not be considered an absolute concept. Both forms of training cause specific morphological changes in the heart, dependent on the type of sport. (Neth Heart J 2008;16:129-33.)
ventricular remodelling; heart; sports; hypertrophy; Prinzmetal angina; acetylcholine; multifocal spasm
One of the diagnostic criteria in order to differentiate between physiological and pathological left ventricular hypertrophy is the wall thickness reduction after at least 3-month detraining period, which is considered a marker of the athlete’s heart. This report describes detraining-related regression of LV hypertrophy and improvement in myocardial deformation in a junior athlete likely to have hypertrophic cardiomyopathy.
Key pointsHypertrophic cardiomyopathy in adolescent athletes can be discovered by 12-lead ECGPhysical training is an important trigger for the clinical presentation of hypertrophic cardiomyopathyReverse LV remodeling (wall thickness reduction) with detraining is a common echocardiographic finding in athletes with physiological hypertrophyThis report demonstrates that reverse remodeling can also be found in adolescent athletes likely to have hypertrophic cardiomyopathy
Athlete’s heart; detraining; echocardiography; hypertrophic cardiomyopathy; left ventricular hypertrophy; myocardial function; strain echocardiography.
Echocardiograms were recorded in 154 active athletes (from various sports) and 21 ex-athletes and compared with those in 40 normal control subjects (non-athletes). Diastolic cavity dimension and posterior wall and septal thickness were measured and left ventricular mass and the ratio of posterior wall thickness to cavity radius and of septum to posterior wall thickness calculated. As a group athletes had a significantly increased diastolic cavity dimension, posterior wall and septal thickness, and left ventricular mass. The ratio of posterior wall thickness to cavity radius was distributed as a single continuous variable with a significantly increased mean, and there was no separate subgroup of shot putters or weight lifters with inappropriate hypertrophy. The mean ratio of septum to posterior wall thickness was normal, but there was a wide range of values up to 2.1:1. Ex-athletes had entirely normal left ventricular dimensions and wall thickness. When athletes are categorised by their standard of competition national standard competitors had a significantly increased posterior wall and septal thickness and left ventricular mass compared with university and non-competitive sportsmen. In conclusion, strenuous activity results in left ventricular hypertrophy which is appropriate to the body size of the athlete and the degree of activity but not to its type.
Anabolic androgenic steroids (AAS) abuse for improving physical appearance and performance in body builders is common and has been considered responsible for serious cardiovascular effects. Due to disagreement about cardiovascular side effects of these drugs in published articles, this case control study was designed to evaluate the echocardiographic findings in body builder athletes who are current and chronic abusers of these drugs.
Body builder athletes with continuous practice for the preceding two years and were training at least twice weekly were selected and divided into AAS abuser and non user and compared with age and BMI matched non athletic healthy volunteers (15 cases in each group).
There was no significant difference in left ventricular size or function either systolic or diastolic in comparison to cases and control groups. The only difference was in diastolic size of septum and free wall but observed differences were only significant (P = 0.05) between first (athletic with AAS abuser) and third group (non athletic and nonuser). The difference between the above-mentioned indexes were not significant between two groups of athletes.
Observed differences in diastolic size of septum and free wall is in favor of that long term abuse of anabolic steroid results in accentuation of physiologic hypertrophy due to long term sport most probably due to higher rate pressure product. Furthermore long term abuse and supra pharmacologic doses do not have significant effect in size and left ventricular function.
Androgenic Anabolic Agent; Body Builder; Left Ventricular Hypertrophy; Echocardiography
To emphasize the potentially harmful effects of high-intensity exercise on cardiac health and the fine line between physiologic and pathologic adaptation to chronic exercise in the elite athlete. This case also highlights the crucial need for regular evaluation of symptoms that suggest cardiac abnormality in athletes.
Sudden cardiac death (SCD) of young athletes is always a tragedy because they epitomize health. However, chronic, high-intensity exercise sometimes has harmful effects on cardiac health, and pathologic changes, such as myocardial fibrosis, have been observed in endurance athletes. In this case, a highly trained 30-year-old cyclist reported brief palpitations followed by presyncope feeling while exercising. Immediate investigations revealed nonsustained ventricular tachycardia originating from the left ventricle on a stress test associated with myocardial fibrosis of the left ventricle as shown with magnetic resonance imaging. Despite complete cessation of exercise, life-threatening arrhythmia and fibrosis persisted, leading to complete restriction from competition.
Hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, myocarditis, postmyocarditis, use of drugs and toxic agents, doping, and systemic disease.
The arrhythmia could not be treated with catheter ablation procedure or drug suppression. Therefore, the athlete was instructed to withdraw completely from sport participation and to have a medical follow-up twice each year.
To our knowledge, no other report of left ventricle exercise-induced fibrosis associated with life-threatening arrhythmia in a living young elite athlete exists. Only postmortem evidence supports such myocardial pathologic adaptation to exercise.
To prevent SCD in young athletes, careful attention must be paid to exercise-related symptoms that suggest a cardiac abnormality because they more often are linked to life-threatening cardiovascular disease.
myocardial fibrosis; high-intensity exercise; sudden death
Objective—In some athletes with a substantial increase in left ventricular wall thickness, it may be difficult to distinguish with certainty physiological hypertrophy due to athletic training from hypertrophic cardiomyopathy. The purpose of the present investigation was to determine whether assessment of left ventricular filling could differentiate between these two conditions.
Design—Doppler echocardiography was used to obtain transmitral flow velocity waveforms from which indices of left ventricular diastolic filling were measured. Normal values were from 35 previously studied control subjects.
Setting—Athletes were selected mostly from the Institute of Sports Science (Rome, Italy), and patients with hypertrophic cardiomyopathy were studied at the National Institutes of Health (Bethesda, Maryland).
Participants—The athlete group comprised 16 young competitive athletes with an increase in left ventricular wall thickness (range 13–16 mm; mean 14). For comparison, 12 symptom free patients with non-obstructive hypertrophic cardiomyopathy were selected because their ages and degree of hypertrophy were similar to those of the athletes.
Results—In the athlete group, values for deceleration of flow velocity in early diastole, peak early and late diastolic flow velocities, and their ratio were not significantly different from those obtained in untrained normal subjects; furthermore, Doppler diastolic indices were normal in each of the 16 athletes. Conversely, in patients with hypertrophic cardiomyopathy, mean values for Doppler diastolic indices were significantly different from both normal subjects and athletics (p = 0·01 to 0·003), and one or more indices were abnormal in 10 (83%) of the 12 patients.
Conclusions—Doppler echocardiographic indices of left ventricular filling may aid in distinguishing between pronounced physiological hypertrophy due to athletic training and pathological hypertrophy associated with hypertrophic cardiomyopathy.
The serum concentration of creatine kinase (CK) is used widely as an index of skeletal muscle fibre damage in sport and exercise. Since athletes have higher CK values than non‐athletes, comparing the values of athletes to the normal values established in non‐athletes is pointless. The purpose of this study was to introduce reference intervals for CK in athletes.
CK was assayed in serum samples from 483 male athletes and 245 female athletes, aged 7–44. Samples had been obtained throughout the training and competition period. For comparison, CK was also assayed in a smaller number of non‐athletes. Reference intervals (2.5th to 97.5th percentile) were calculated by the non‐parametric method.
The reference intervals were 82–1083 U/L (37°C) in male and 47–513 U/L in female athletes. The upper reference limits were twice the limits reported for moderately active non‐athletes in the literature or calculated in the non‐athletes in this study. The upper limits were up to six times higher than the limits reported for inactive individuals in the literature. When reference intervals were calculated specifically in male football (soccer) players and swimmers, a threefold difference in the upper reference limit was found (1492 vs 523 U/L, respectively), probably resulting from the different training and competition demands of the two sports.
Sport training and competition have profound effects on the reference intervals for serum CK. Introducing sport‐specific reference intervals may help to avoid misinterpretation of high values and to optimise training.
Data from ambulatory electrocardiographic recording in 35 highly trained endurance athletes and in 35 non-athletic controls of similar ages are given. The minimal, mean hourly, and maximal heart rates were significantly lower in the athletes. Thirteen athletes (37 . 1%) but only two controls (5 . 7%) had sinus pauses exceeding 2 . 0 seconds. First degree atrioventricular block was observed in 13 athletes (37 . 1%) and five controls (14 . 3%), second degree Wenckebach type block in eight athletes (22 . 9%) and two controls (5 . 7%), and second degree block with Mobitz II-like pattern in three athletes (8 . 6%) and no control. All athletes with Mobitz II-type pattern also had first degree and Wenckebach-type second degree atrioventricular block. The behavior of sinus rate on development of atrioventricular block varied, not only interindividually but also intraindividually, from absence of change to an increase or decrease in most subjects in both study groups. A decrease in sinus rate on appearance of atrioventricular block was found constantly in only two athletes and one control. Atrioventricular dissociation with junctional rhythm occurred in seven athletes (20%) and with ventricular rhythm in one athlete. Neither of these phenomena was seen in the group of controls. The athletes had slightly fewer ventricular extrasystoles than controls, and no athlete had ventricular tachycardia, whereas two controls had ventricular tachycardia.
In studies of the right ventricle the complexities of chamber shape may be overcome by use of multiple tomographic imaging planes. An established protocol for the echocardiographic description of the heart was used to examine the right ventricle in an ordered series of transducer locations and orientations. Diastolic measurements were made of the right ventricular inflow tract, outflow tract, and right ventricular body, and the range and reproducibility of normal values for cavity size and right ventricular free wall thickness were established. These measurements of cavity size in 41 normal subjects were highly reproducible and the views that were used correctly described the truncated and ellipsoidal shape of the right ventricular inflow tract and body with a separately aligned outflow tract. Cavity trabeculation prevented measurement of the free wall thickness in some areas; however, values of nearly twice the previously reported upper limit of normal for anterior regions were measured from the apex or lateral right ventricular wall. These normal data provide a basis for future echocardiographic studies of the right ventricle.
Good nutritional practices are important for exercise performance and health during all ages. Athletes and especially growing children engaged in heavy training have higher energy and nutrient requirements compared to their non-active counterparts. Scientific understanding of sports nutrition for the young athlete is lacking behind the growing number of young athletes engaged in sports. Most of the sports nutrition recommendations given to athletic children and adolescents are based on adult findings due to the deficiency in age specific information in young athletes. Therefore, this review reflects on child specific sports nutrition, particularly on carbohydrate intake and metabolism that distinguishes the child athlete from the adult athlete. Children are characterised to be in an insulin resistance stage during certain periods of maturation, have different glycolytic/metabolic responses during exercise, have a tendency for higher fat oxidation during exercise and show different heat dissipation mechanisms compared to adults. These features point out that young athletes may need different nutritional advice on carbohydrate for exercise to those from adult athletes. Sport drinks for example may need to be adapted to children specific needs. However, more research in this area is warranted to clarify sports nutrition needs of the young athlete to provide better and healthy nutritional guidance to young athletes.
Key pointsAthletic girls show lower carbohydrate intakes compared to boys.Substrate oxidation during exercise appears to be maturity related, fat being the preferred fuel for oxidation in younger athletic children.Children appear to have lower endogenous but greater exogenous carbohydrate oxidation rates during exercise.Carbohydrate intake during exercise appears to show no additional performance improvement in young athletes. Perhaps fat intake or a combination of both nutrients may be a better approach for nutrient supplementation during exercise.Gastric emptying physiology of young athletes is not well known. Adult sport drinks showed a tendency to delay gastric emptying in young athletes during exercise at higher intensities.More research is needed in paediatric sports nutrition.
Exercise; diet; nutrients; children; sport drinks
Competitive athletics is often associated with moderate left ventricular (LV) hypertrophy, and it has been hypothesized that training mode and type of exercise modulates long-term cardiac adaptation. The purpose of the study was to compare cardiac structure and function among athletes of various sports and sedentary controls. Standard transthoracic two-dimensional M-mode and Doppler echocardiography was performed at rest in Caucasian male canoe/kayak paddlers (n = 9), long distance runners (LDR, n = 18), middle distance runners (MDR, n = 17), basketball players (BP, n = 31), road cyclists (n = 8), swimmers (n = 10), strength/power athletes (n = 9) of similar age (range, 15 to 31 yrs), training experience (4 to 9 years), and age-matched healthy male sedentary controls (n = 15). Absolute interventricular septum (IVS) thickness and LV wall thickness, but not LV diameter, were greater in athletes than sedentary controls. Left ventricular mass of all athletes but relative wall thickness of only BP, swimmers, cyclists, and strength/power athletes were higher as compared with controls (p < 0.05). Among athletes, smaller IVS thickness was observed in MDR than BP, cyclists, swimmers or strength/power athletes, while LDR had higher body size-adjusted LV diameter as compared to BP, cyclists and strength/power athletes. In conclusion, relative LV diameter was increased in long distance runners as compared with basketball players, cyclists, and strength/power athletes. Basketball, road cycling, strength/power, and swimming training were associated with increased LV concentricity as compared with paddling or distance running.
Key pointsThe type of cardiac hypertrophy seems to be only moderately exercise-specific.Long-distance runners develop larger left ventricular dilation as compared with basketball players, cyclists, and strength/power athletes.Myocardial wall thickening is triggered by different sporting activities that involve large muscle groups.
Myocardial hypertrophy; left ventricle; echocardiography; athlete
Background: Childhood obesity and hypertension are global problems that are on the rise in India. Improving physical activity is an accepted main line of strategy for overcoming poor body composition, hypertension and reduced cardio respiratory fitness (CRF) all of which are considered as independent risk factors for the development of future cardiovascular complications.
Aim: Present study was conducted to evaluate the effect of regular unstructured physical training and athletic level training on anthropometric measures, body composition, blood pressure and cardio respiratory fitness in adolescents.
Settings and Design: This is a collaborative study between the Department of physiology, Jawaharlal Institute of Postgraduate Medical Education and Research and Residential school, Jawahar Navodhya Vidyalaya, Puducherry, India.
Method and Material: Student volunteers in the age group of 12–17 years were classified into athletes (group 1) and physically active non-athletes (group 2). Parameters measured and calculated were weight, height, body mass index, waist and hip circumference, body fat percentage (BF%), fat free mass (FFM), Systolic (SBP) & Diastolic blood pressure (DBP), Mean arterial pressure (MAP), Rate pressure product (RPP) and Predicted VO2 max.
Statistical Analysis used: Mean difference between the groups was analysed using unpaired Student’s t–test. All statistical analysis was carried out for two-tailed significance at the 5 % level using SPSS version 19 (SPSSInc, USA).
Results: Anthropometric measures, body composition measures and blood pressure values of both the group students were within the normal limits. There was no significant difference in anthropometric and body composition parameters between the group 1 and group 2 students. DBP, MAP and RPP were significantly lower in group 1 students when compared to group 2 students. VO2 max values were more in group 1 girls as compared to group 2 girls while the values of boys were comparable between the two groups.
Conclusion: Regular unstructured physical activity for 60 minutes daily for the duration of one year can help the students to maintain their anthropometric parameters, body composition measures and CRF at par with the athletes of the same age and gender. However, athletic level training further reduces the cardiovascular load of the adolescent students.
Physical activity; Body composition; Fat free mass; Cardio respiratory fitness
Core stability training, operationally defined as training focused to improve trunk and hip control, is an integral part of athletic development, yet little is known about its direct relation to athletic performance.
This systematic review focuses on identification of the association between core stability and sports-related performance measures. A secondary objective was to identify difficulties encountered when trying to train core stability with the goal of improving athletic performance.
A systematic search was employed to capture all articles related to athletic performance and core stability training that were identified using the electronic databases MEDLINE, CINAHL and SPORTDiscus™ (1982-June2011).
A systematic approach was used to evaluate 179 articles identified for initial review. Studies that performed an intervention targeted toward the core and measured an outcome related to athletic or sport performances were included, while studies with a participant population aged 65 years or older were excluded. Twenty-four in total met the inclusionary criteria for review.
Study appraisal and synthesis methods
Studies were evaluated using the Physical Therapy Evidence Database (PEDro) scale. The 24 articles were separated into three groups, general performance (n = 8), lower extremity (n = 10) and upper extremity (n = 6), for ease of discussion.
In the majority of studies, core stability training was utilized in conjunction with more comprehensive exercise programmes. As such, many studies saw improvements in skills of general strengths such as maximum squat load and vertical leap. Surprisingly, not all studies reported measurable increases in specific core strength and stability measures following training. Additionally, investigations that targeted the core as the primary goal for improved outcome of training had mixed results.
Core stability is rarely the sole component of an athletic development programme, making it difficult to directly isolate its affect on athletic performance. The population biases of some studies of athletic performance also confound the results.
Targeted core stability training provides marginal benefits to athletic performance. Conflicting findings and the lack of a standardization for measurement of outcomes and training focused to improve core strength and stability pose difficulties. Because of this, further research targeted to determine this relationship is necessary to better understand how core strength and stability affect athletic performance.
Short stature and later maturation of youth artistic gymnasts are often attributed to the effects of intensive training from a young age. Given limitations of available data, inadequate specification of training, failure to consider other factors affecting growth and maturation, and failure to address epidemiological criteria for causality, it has not been possible thus far to establish cause–effect relationships between training and the growth and maturation of young artistic gymnasts. In response to this ongoing debate, the Scientific Commission of the International Gymnastics Federation (FIG) convened a committee to review the current literature and address four questions: (1) Is there a negative effect of training on attained adult stature? (2) Is there a negative effect of training on growth of body segments? (3) Does training attenuate pubertal growth and maturation, specifically, the rate of growth and/or the timing and tempo of maturation? (4) Does training negatively influence the endocrine system, specifically hormones related to growth and pubertal maturation? The basic information for the review was derived from the active involvement of committee members in research on normal variation and clinical aspects of growth and maturation, and on the growth and maturation of artistic gymnasts and other youth athletes. The committee was thus thoroughly familiar with the literature on growth and maturation in general and of gymnasts and young athletes. Relevant data were more available for females than males. Youth who persisted in the sport were a highly select sample, who tended to be shorter for chronological age but who had appropriate weight-for-height. Data for secondary sex characteristics, skeletal age and age at peak height velocity indicated later maturation, but the maturity status of gymnasts overlapped the normal range of variability observed in the general population. Gymnasts as a group demonstrated a pattern of growth and maturation similar to that observed among short-, normal-, late-maturing individuals who were not athletes. Evidence for endocrine changes in gymnasts was inadequate for inferences relative to potential training effects. Allowing for noted limitations, the following conclusions were deemed acceptable: (1) Adult height or near adult height of female and male artistic gymnasts is not compromised by intensive gymnastics training. (2) Gymnastics training does not appear to attenuate growth of upper (sitting height) or lower (legs) body segment lengths. (3) Gymnastics training does not appear to attenuate pubertal growth and maturation, neither rate of growth nor the timing and tempo of the growth spurt. (4) Available data are inadequate to address the issue of intensive gymnastics training and alterations within the endocrine system.
Electronic supplementary material
The online version of this article (doi:10.1007/s40279-013-0058-5) contains supplementary material, which is available to authorized users.