The effect of nitric oxide donors on improving the functional capabilities of the cardiovascular system and special training of representatives of power sports

Abstract

Introduction. The analysis of the data available in the scientific and methodological literature supports the general opinion that nitric oxide makes the recovery process after intensive training more eficient, which helps prevent the growth of fatigue and the formation of overstrain processes in sports. At the same time, nitric oxide donors are considered to be excellent pre-workout means, and their use in any form – as pharmaceuticals or special dietary supplements for athletes – allows to significantly improve the quality of training and ensure an increase in the eficiency of the competitive period. However, these data mainly relate to athletes of cyclic sports events and train such a motor quality as endurance. Therefore, it seems relevant to investigate the impact of nitric oxide donors (antecedents or precursors) on the functional state of the heart in relation to special training status indices in strength sports events.

The objective of the study is to evaluate the safety and mediated effectiveness of using a pharmacological complex based on nitric oxide donors for the prevention and correction of cardiac dysfunction and special training status improvement in representatives of strength sports events.

Material, methods and organization of the study. The following complex methodology was applied, which included theoretical methods incorporating analysis and generalization of pedagogical and scientific-methodical literature, empirical methods, pedagogical experiment, mathematical and statistical methods envisaging calculations of significance of data differences between groups of athletes and correlation analysis of indices.

The preliminary evidence-based study of the safety of using a special dietary supplement “Arginine + Citrulline” (manufactured by Now Food, USA) was based on dynamic monitoring of the main laboratory indices of hematological and biochemical homeostasis, as well as changes in lactate content. At the next stage of the study, the level of cardiomarkers (cardiac troponins T and I) in the blood serum was determined, as well as indices of special training status in representatives of strength sports events (through the example of skilled weightlifters) were investigated by the method of V.M. Abalakov.

During the randomized, double-blind, placebo-controlled study, 24 skilled weightlifters were divided into the main (14 participants) and control (10 participants) groups by simple stratification method. Representatives of the main group used a special sports dietary supplement “Arginine + Citrulline”, in a daily dose of 2 capsules of 500 mg of active substance, whereas those of the control group – placebo (capsules with starch) for 30 days in the dynamics of the training process. Laboratory and pedagogical researches were carried out synchronously at the beginning and the end of the experiment which was conducted in dynamics of the general preparatory stage of the preparatory period. The same program of training was used by athletes of both groups.

Results of the study. The obtained data on the safety assessment of the use of a special dietary supplement proved the lack of changes in the values of standard laboratory hematological and biochemical parameters in the dynamics of the experiment. In addition, the results of the study indicate, firstly, the absence of the acid-base balance deterioration, for which changes in the lactate content towards accumulation are largely responsible, and, secondly, the absence of shifts in the trigger mechanism that “launches” the process of fatigue and is mediated by changes in the lactic acid content in the athlete’s body.

The findings show that the baseline content values of both cardiac troponins – cTnT and cTnI – before the study did not practically differ from those of healthy donors, thus indicating the lack of cardiac lesions in athletes during the standard training process. At the end of the 30-day monitoring period during intense physical loads peculiar to strength sports events in general and weightlifting in particular, a significant increase in the content of both cardiac troponins was observed in the control group compared to the data of donors and the results observed before the study. This is indicative of the changes in the integrity of myocardial cells under the influence of various metabolic changes in the dynamics of physical loads of high volume and intensity. As concerns the data of the main group of weightlifters, the positive effect of using the special sports dietary supplement “Arginine + Citrulline”, which provides increased coronary and improved heart tissue circulations, is quite evident. They are additionally protected by L-citrulline malate, which binds and removes toxic substances from myocardial cells that accumulate during regular weightlifting training sessions. Therefore, the data obtained prove conclusively the preventive effect of an ergogenic and restorative extra-training product.

Pedagogical testing of special physical training status indices in representatives of strength sports events. The data obtained indicate that the course use of a special dietary supplement simultaneously containing two nitric oxide donors has a positive effect on special training status parameters related to muscular and neuromuscular coordination. This is realized in such an index of weightlifters’ functional fitness as explosive power.

The results of the correlation analysis confirmed the authors’ assumption about a close relationship between the content of cardiac troponins and the results reflecting the special training status of weightlifters in terms of the height of the barbell lift in standing jump and snatch row and the time of these testing exercises performance. The improvement of special training status indices reflecting changes in explosive power has become a direct confirmation of the positive effect of the course application of a complex of nitric oxide donors and a detoxifier on the heart muscle structure. Thus, in the main group, the height of the barbell lift during the standing high jump and snatch row increased significantly by 31.43 % compared to the baseline data, and 12.89 %, respectively, along with a simultaneous decrease in the time of executing the control exercises by 18.87 % and 21.54 %, respectively.

Conclusions. Thus, the existence of significant correlations confirms our hypothesis that the improvement of the heart functional state during strength loads with the use of nitric oxide donors due to blood circulation acceleration, which is more typical of cyclic loads (“endurance”), despite the predominantly anaerobic mechanism of energy supply of muscular activity of weightlifters, has a positive effect on the indices of their special training status. This substantiates the expediency and effectiveness of both the use of nitric oxide donors (precursors) in representatives of sports with a predominantly anaerobic character of energy supply of skeletal muscle contractile activity and the practicability of including developing aerobic microcycles in the training process in such cases.