Significance of cortisol in the control of training in elite swimmers
According to the training theory, below-optimum training volume and intensity may not results in the greatest possible gain in performance, while above-optimum training volume and intensity may lead to a condition of over-training, with a strong decline in performance and the appearance of specific symptoms. Over-training syndrome has been defined as an imbalance between stress and stress tolerance, in which stress is represented by the sum of training and non-training stress factors.
Over-training can be prevented by : a) matching recovery with the specific stress or stressors, b) planning the training program with a correct workload and adequate periods of regeneration, and c) monitoring the individual response in training load. It is well known that training can induce modifications in hormone plasma concentrations. The modifications may have important implications for the rate and duration of adaptation processes involved in training. It has been suggested that cortisol is one of the most important hormones indicating a stressful condition,. In our studies in swimmers, increased training volume was associated with impaired performance and elevated basal plasma concentrations of cortisol, while a decrease in pre-competition cortisol levels indicate over-training. However, an up-regulation of glucocorticoid receptors concomitant the increase in resting cortisol levels and explosive performance related to actual cortisol levels. Hence, the adaptive phase could be characterized by a high glucocorticoid receptor binding capacity related to actual cortisol levels. The dynamic control of sensitivity to cortisol can modulate the response to stress, especially when the stress is prolonged. The evaluation of glucocorticoid receptor binding capacity related to actual cortisol levels could be a good method to monitor training response in swimmers; high resting levels of cortisol with a low glucocorticoide receptor binding capacity could indicate a high risk of over-training.
Acoustic stimulation as a new element for the improvement of swimming performance
GALMONTE A.,RIGHI G., AGOSTINI T.
The goal of experimental sport psychology is both to provide each athlete with the guidelines to be aware of the relevant resources and to address the energy into the search of the most helpful information traceable in the environment. A number of studies have shown that a relevant information is the acoustic one which is embedded within the rhythmic cycle of the athletic gesture. The present research, devoted to swimming, is aimed to implement a strategy to improve the performance starting from the rhythmic hypothesis according to which an acoustic model of the best performance, developed and chosen together with the athlete, can improve the results by means of a standardization of the leg/arm cycle.
Disposition to optimism and sport performance: A study on master swimmers
LUCIDI L., CEI A.
Aim of the research is to investigate on the relationship between optimism and fifty four swimmers at " master level"; 28 men and 26 women, aged from 22 to 55 years, participated at the research. Subjects were asked to answer to the Attributional Style Questionnaire (ASQ, Peterson et al. 1991)and to revised version of the
About one month later, at the end of one of the usual timekeeping test provided for the training program, the coach gave to each of the participants a false feed back about the results of the test, making him/her believe to have obtained an excessively higher time in front of his potential and asking him/her to repeat the test.
An index of the differences between the two performances has been calculated and has been utilised as independent variable within a multiple regression which considered the scores of ASQ and LOT-R as predictors.
The results show that both these predictors contribute significantly to determine the forecast.
Energetic and nutritional supplies of the swimmers
BERNARDI B.,BERNARDI M.
The large volume of intensive training of elite swimmers imposes a big demand on energy supplì. The energy requirement of a swimmers who train 4h-day-1 correspond to 16.8-22.6 MJ ( 4000-5000 kcal) for males and 14.2-16.8 MJ ( 3400-4000 kcal) for females. Generally males tend to remain in energy balance ( -30% of energy expenditure). Carbohydrate needs correspond to those suggested for athletes with moderate to high intensity exercise sessions ( 7-10 g-kg-1 body mass).Chronic glycogen depletion can occur among competitive swimmers because of intensive training. Protein needs are slightly higher than those of other sport athletes ( 1.5-2.0 g-kg-1 body mass.). Evidence of iron, calcium and zinc deficiencies are often observed in female swimmers. Swimmers should pay attention to assume sufficient amount of water and antioxidants.
Analyses of the main reason for drop outs in young Slovenian swimmers
TUSAK M,FAGANEL M.
In the limits of theoretical frames the AA are tying to represent the main reasons for drop outs in young swimmers (11-14 years) in Slovenia. The problems in motivations are common in science magazines worldwide and therefore contribute and inspire new researches. Scientists think that the developmental factors and personality priorities also impact on athlete's stability to stay in sport or to give up. Children's motivation to play in sport is different to the motivation of a professional athlete to achieve medals on Olympic Games or to live on sport and earn money- More as the Authors understand specific developmental phases , easier it will be to positively impact on athlete ,his or hers achievements and state of health in sport
The scientific support to Slovenian swimmers from junior to senior swimmers groups
The system of scientific support to swimmers is bases on cooperation between Slovenian Swimming Federation and Faculty of Sport. The system is financed by the Ministry of Education, Science and Sport and by the Foundation for the financing of sport organizations. Following the aims of rationally and practice regarding consultations to coaches and swimmers the Author created the system of group mechanism for age group swimmers and individual system to the Slovenian swimmers.
The system of the scientific support to the Slovenian swimmers is presented and some experiences how can swimmers and their coaches get benefits from different information obtained by this measurement system are reported
Energy cost of swimming
The amount of metabolic energy spent in transporting the body mass of the subject per unit of distance has been defined as the energy cost of locomotion /C, kJ km-1 or J m-1 kg-1) and it id the modt appropriate way for quantifying the economy of progression. C can be calculated either including or subtracting the metabolic energy turnover at rest. C has been described as the most important physiological determinant of best performance times in several forms of human locomotion, including swimming. Indeed, the best performance times improvement brought about by the decrease of C alone account for 12-55% of the improvement obtained when all the considered physiological factors determining performance are modified together by the same amount.
In this paper the relationship between the energy cost of swimming and the speed of progression will be illustrated in the four classical swimming styles in group of athletes of different technical skill. Moreover, it will be shown how the different hydrostatic feature of men and women can be quantitatively described and measured and how these differences may account for the differences of C existing between the two sexes
Doping: From substances of natural origin to genetic engineering
GIRALDI T., SCHILLANI G.
The use of substances capable to significantly increase sport performances remarkably increased after the Second World War, and has been accompanied by similarly pronounced adverse effects.
Biotechnologies, and recombinant DNA techniques , have made it possible to synthetize erithropoietin as well as other human proteins, which induce a very promoumced enhancement in sport performances which is accompanied by similarly pronounced difficulties in identification. An additional concern arises from the translation of genetic molecular medicine to sport science in terms of gene doping methods.
World Anti-Doping Agency (WADA) imposed to the world of sport prohibitions concerning the use of substances and methods, achieving a limited success because of the difficulties in demonstrating illicit behaviour deriving from the use of masking agents, of analytical difficulties and of the use of designer drugs. An additional problem encountered is that of nutritional supplements containing prohibited substances.
It is therefore unfortunately likely the use of doping will continue in spite of the use of restrictions, and that gene methods will be a serious threat to the health in the world of sport
A model to estimate propelling efficiency in front crawl
ZAMPARO P., GRAZZINA F., DURI M.
In this paper a model to calculate the propelling efficiency ( ?o ) in front crawl is presented. The model compares the motion of the arm stroke to that of a paddle-wheel and allows to calculate on the basis of simple measurements such as the swimming speed (v), the stroke frequency (SF). And the shoulder to hand distance (l). These parameters were calculated in a group of 17 swimmers of different technical skill (8 male and 5 female swimmers competing at national level and 4 amateur female swimmers). The results show that ?o is larger in male ( 0.39 ± 0.05) than in female (2.35 ± 0.01) swimmers of technical skill and that ?o is lowest in the group of female amateurs swimmers ( 0.29±0.03). differences in ?o is the distance covered per stroke (v/SF)
Moreover, the data indicates that the most important parameter in determining the observed inter-individual