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JOURNAL
OF
SPORTS SCIENCE &
MEDICINE
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Research
article
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ECHOCARDIOGRAPHIC PARAMETERS IN ATHLETES OF DIFFERENT SPORTS |
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Tomas Venckunas1  ,
Arimantas Lionikas1,2, Jolanta
E. Marcinkeviciene3, Rasa Raugaliene1,3,
Aleksandras Alekrinskis1 and Arvydas
Stasiulis1 |
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1Department of Applied Physiology and Sports Medicine, Lithuania Academy of Physical Education, Kaunas, Lithua-nia, 2Center for Developmental and Health Genetics, Pennsylvania State University, University Park, Pennsylvania, USA, 3Institute of Cardiology, Kaunas University of Medicine, Kaunas, Lithuania. |
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© Journal of Sports Science and Medicine (2008) 7, 151 - 156 Search Google Scholar for Citing Articles |
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| ABSTRACT | ||||||||||||
| 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 words: Myocardial hypertrophy, left ventricle, echocardiography, athlete. |
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| INTRODUCTION | ||||||||||||
| Regular participation in competitive sports frequently causes
moderate left ventricular (LV) hypertrophy, the type and extent of which
depend on the amount and intensity of the training (Fagard, 2003;
Pluim et al., 2000).
It has been suggested that intense isometric (anaerobic, strength/power)
exercise training results in a more concentric LV hypertrophy, which is
characterized by an increase in LV mass with also an augmented ratio of
wall thickness to the LV diameter (Haykowsky et al., 2002),
whereas extensive isotonic (aerobic, endurance) exercise training results
in a more prominent enlargement of LV diameter (George et al., 1991;
Morganroth et al., 1975;
Pluim et al., 2000;
Snoeckx et al., 1982).
Some (Csanady and Gruber, 1984; Gates et al., 2004) but not the other (Haykowsky et al., 2000; 2002; Wernstedt et al., 2002; Whyte et al., 2004) groups have found the evidence of dichotomous cardiac adaptation to strength/power versus endurance training. However, differences in echocardiographic indices between marathon runners, cyclists and triathletes (Hoogsteen et al., 2004), as well as between handball players and canoe/kayak paddlers (Gates et al., 2004), have been reported suggesting sport-specific adaptation. Furthermore, it has been proposed that the structural cardiac adaptation to endurance exercise training depends on the group of muscles, i.e., those of lower or upper extremities, primarily involved (Csanady and Gruber, 1984; Gates et al., 2003, 2004). However, specificity of the pattern of cardiac hypertrophy in response to various training programs remains ambiguous (Baggish et al., 2007; Barbier et al., 2006; Naylor et al., 2008) as in many studies no evidence of dichotomous cardiac adaptation has been found even between the strength/power and endurance athletes (Haykowsky et al., 2000; 2002; Shapiro, 1984; Wernstedt et al., 2002; Whyte et al., 2004). To shed more light on the specificity of cardiac hypertrophy, we compared echocardiographic indices of athletes of seven different sports disciplines and sedentary controls, with particular attention to the type of myocardial geometric pattern. In the present study we chose to investigate distance runners and road cyclists, who do minimal strength training but cover substantial mileage; basketball players, who train and compete in predominantly anaerobic bursts (Balciunas and Stonkus, 2003); swimmers, in which case horizontal position and water submersion during training is dominant; flat- water paddlers, who perform mostly upper-body training of both aerobic and anaerobic type (Shephard, 1987; Tesch, 1983); and strength/power athletes from predominantly combat sports. We hypothesized that training mode and type of exercise might differentially affect characteristics of cardiac adaptation. |
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| METHODS | ||||||||||||
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Subjects Echocardiography Statistical
analysis |
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| RESULTS | ||||||||||||
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Anthropometric
characteristics of the subjects were significantly influenced by the grouping
variable (Table 1). As expected,
basketball players were the tallest of all groups, and heavier than runners,
cyclists or controls (p < 0.05). Distance runners had lower body mass,
body mass index, and BSA than paddlers and strength/power-trained athletes. |
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| DISCUSSION | ||||||||||||
| The results
of this study support the notion that regular exercise training induces
cardiac hypertrophy that may be manifested by the LV wall thickening and
cavity dilation in young athletes. The former aspect of adaptation was observed
in all athletes, whereas the latter was specific to the distance runners. Early echocardiographic studies suggested that the type of myocardial hypertrophy depends on the athletic training program, e.g. preferentially increased LV diameter was found in endurance athletes whereas preferentially increased LV thickness in strength athletes (Morganroth et al., 1975; Snoeckx et al., 1982). Subsequent studies, however, were frequently in discord with that dichotomy of the cardiac structural patterns in athletes. For instance, even very intense strength training aimed at increasing skeletal muscle power/strength/mass would not necessarily result in cardiac wall thickening (Bertovic et al., 1999; Haykowsky et al., 2002; Pelliccia et al., 1993; Wernstedt et al., 2002; Whyte et al., 2004) or the resultant myocardial structure in strength/power athletes would not differ from that of endurance athletes (Legaz Arrese et al., 2005; Pelliccia et al., 1999; Urhausen and Kindermann, 1999; Wernstedt et al., 2002; Whyte et al., 2004). Similarly increased LV mass in all of our athlete groups but some sports-specific differences in echocardiographic parameters suggest the possibility that there is a generic response to exercise (an increased cardiac mass) (Barbier et al., 2006; George et al., 1991; Shapiro, 1984), with (only) some specific effects on various cardiac structural or functional characteristics (Barbier et al., 2006). While the increase in myocardial mass might be influenced by the exercise-related rise in concentration of anabolic hormones (Cumming et al., 1986; Vogel et al., 1985), mechanisms underlying sports-specific influences remain unknown. Increased myocardial mass due to both cavity dilation and wall thickening is a usual finding in endurance runners (Fagard, 2003; Pluim et al., 2000). It is believed that the increased volume loading during exercise triggers cardiac adaptation in endurance athletes. Additionally, it has also been proposed that the increase in diameter of the LV may be due to stretch of myocardium at rest because of the prolonged filling time associated with bradycardia (Rowell, 1986). The dilation of ventricle is believed to occur via elongation of cardiac myocytes (George et al., 1991). In the present study, long distance runners (but not middle distance runners) had a larger relative LV diameter than basketball players, cyclists, strength/power athletes, or controls (Table 2). The fact that middle distance runners did not differ significantly might be related to the difference in duration of the training stimulus between the long and middle distance runners, as it has been shown that marathoners spend more time for their training than middle distance runners of similar competitive level (Venckunas et al., 2005). Thus, our observation is consistent with the hypothesis that increased exercise-induced volume overload triggers myocardial dilation and indicates that duration of the stimulus is an important factor for the left ventricular chamber enlargement. Due to the specific technique in flat-water paddling this discipline is particularly demanding for both aerobic and anaerobic capacity of upper body musculature (Shephard, 1987; Tesch, 1983) while lower body is much less involved. This upper-to-lower body imbalance contrasts paddling from other sports disciplines of the present study, providing a model to explore if preferential involvement of different muscle groups plays a role in cardiac adaptation. Several studies reported thicker myocardial walls in individual elite paddlers than athletes from majority of other sports (Csanady and Gruber, 1984; Pelliccia et al., 1991; Pluim et al., 2000). In our study, however, neither high-performance paddlers had exceptionally thick LV walls nor the group of paddlers differed from the other groups of athletes in any parameters of cardiac morphology. Similar absence of difference in myocardial wall thickness between paddlers and endurance athletes was also documented by other echocardiographic studies (Iglesias Cubero et al., 2000; Pelliccia et al., 1999; Whyte et al., 2004). Thus these findings argue against marked differences in LV adaptation to upper versus lower body training, although it has to be acknowledged that detection of possible subtle variations might have been precluded by modest sample size. Possible explanation for the discrepancy between the results of different studies might be related to variation in training regimen (season, specificity) and usually limited statistical power to detect subtle differences. |
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| AUTHORS BIOGRAPHY | |
Tomas VENCKUNAS Employment: Department of Applied Physiology and Sports Medicine, Lithuanian Academy of Physical Education. Degree: PhD (Biology). Research interests: Cardiovascular adaptation to exercise training. E-mail: t.venckunas@gmail.com |
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Arimantas LIONIKAS Employment: Center for Developmental and Health Genetics, Pennsylvania State University. Degree: PhD (Biology). Research interests: Muscle biology and genetic influences. E-mail: aul104@psu.edu |
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Jolanta Elena MARCINKEVICIENE Employment: Institute of Cardiology, Kaunas University of Medicine. Degree: PhD, MD. Research interests: Cardiovascular alterations in response to pathological and physiologic overload. E-mail: jolantamar@yahoo.com |
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Rasa RAUGALIENE Employment: Department of Applied Physiology and Sports Medicine, Lithuanian Academy of Physical Education; Institute of Cardiology, Kaunas University of Medicine. Degree: PhD, MD. Research interests: Changes in cardiac function in patients and athletes. E-mail: rasara@takas.lt |
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Aleksandras ALEKRINSKIS Employment: Depart. of Applied Physiology and Sports Medicine, Lithuanian Academy of PE. Degree: PhD. Research interests: Short- and long-term adaptation to paddling training. E-mail: a.stasiulis@lkka.lt |
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Arvydas STASIULIS Employment: Professor, Department of Applied Physiology and Sports Medicine, Lithuanian Academy of Physical Education. Degree: PhD. Research interests: Aerobic capacity and its changes under different conditions including neuromus-cular fatigue. E-mail: a.alekrinskis@lkka.lt |
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