TAKE-OFF STRUCTURE AND TOUCH DOWN LOADS DURING LANDING IN SELECTED RHYTHMIC SPORT GYMNASTICS JUMPS

INTRODUCTION: Jumps can be found in various sport disciplines, and the technique of execution depends on the specifics of the event. In the case of rhythmic sport gymnastics, jumps as well as turns, elements of flexibility and balance in connection with the use of equipment are some of the elements assessed in competition. Each jump must have a form defined in the rules. A long flight phase makes possible the execution of the desired form of a jump. Rhythmic sport gymnastics is one of the sports disciplines with early specialization, which means that girls start training when they are five years old. The specific character of this discipline consists in repeating elements of technique, which means that dozens of jumps are done landing on one or two legs during each training session. Counting the number of repetitions, the number of practice sessions in a week and multiplying by the number of weeks in the year - in the case of the youngest girls - we get about six thousand repetitions. Cumulating loads while landing and the specific structures of children’s bones are the cause of repetitive strain injury, especially to the knee and ankle joints. Research on the structure of take-offs in jumps is referred to for factors that contribute to achieving maximum length and height of jump (Aura & Viitasalo, 1989; Dowling & Vamos, 1993; Janiak, Eliasz & Gajewski, 1997), but few works deal with the landing phase and the resulting loads on the movement system. Investigations point to the importance of co-ordination, specifically of the movement of the upper extremities in the take-off phase, which may depend on the synchronization of the movements of the lower and upper extremities and trunk (Aragon-Vargas & Gross, 1997). Some authors have found that the arm swing improved the jump height (Shetty & Etnyre, 1989), increased the downward load on the legs (Amin & Bober, 1989), and enhanced the impulse generated by the lower extremities by lengthening the time of force application (Harman et al.,1990). However, in the cited papers the authors did not consider the influence of arm swinging on load parameters during the landing phase. The aim of this paper is to define the value of the reaction force which must be absorbed during the landing phase and to investigate the share of the upper extremities in damping touch down loads in jumps with different difficulty levels

PRECISION OF MANIPUtATION MOVEMENTS OF 7-15 -YEARS – OLD CHILDREN IN CONTINUOUS AND CROSS-SECTION INVESTIGATION

Early specialization can be noticed in many sports events Although it is easy to evaluate child's strength, speed and endurance capabilities and apply proper , training means, it is difficult to evaluate the efficiency of the process of movement steering Neuro-muscle coordination as the process taking place in the muscular and nervous systems IS the factor which determines the degree of mastering a sports technique as well as the economical use of capabilities of the motor system. As neuro-muscular coordination cannot be evaluated directly, it is done indirectly by the evaluation of movement coordination. It has been assumed that the precision of manipulation movements accompanied by external disturbances may be the criterion of the evaluation of movement coordination. Precision of the movement manipulation has been evaluated on the basis of the test conducted on the MURP (electronic indicator of the error of movement) The subject was required to lead the slider so that the tip of the indicator travelled precisely along the path. The motion was disturbed by the magnetic field generated by the electromagnets The test was performed during five by four groups of children (n = 240). The aim of the investigation was to find out if the changes in the steering quality take place together with the child's physical development The greatest differentiation of manipulation movement precision has been found among 9.5- 10.5-year-old girls and 10.5-1 1 5-year-old boys We may assume that is a stimulation phase of the steering process in the neuro-muscular system the fact that 12.5-year-old girls and 13.5-year-old boys show stabilization of manipulation movement precision may be the proof for the maturity of their nervous system

Relative power of the lower limbs in drop jump

The purpose of this paper was to determine the power produced by the lower limbs in the take-off phase in drop jumps (DJ) and the correlation between the power and load measured by dropping height after take-off. The research group (N = 17) contained students practicing football, volleyball, basketball, athletics, high jump, swimming and fencing. The individual characteristics 'power-load' of the players and the observation of the changes during the training process enable the coaches to choose precise loads and at the same time to improve the training. The criterion of choosing loads in the plyometric training may be relative power output of lower limbs referred to the DJ height. While the condition allowing player to perform this type of training may depend on obtaining greater power in drop jump than in counter movement jump

Porównanie jakości herbatek miętowych dostępnych w sieci handlowej

Mint herb, commonly used in traditional medicine, is mainly consumed in the form of teas. Mint is characterized by antioxidant, antibacterial, hypoallergenic and immunomodulatory effects, as well as is benecial to the digestive tract. It is an excellent cholagogue, low diastolic, carminative and appetite stimulant. Used in the form of inhalation against runny nose, pharyngitis and bronchitis, it works weakly antiseptic. The aim of this study was to evaluate and compare the qualitycharacteristics of selected mint teas from diferent producers. 19 peppermint teas, in bags and without bags, were tested. Color measurements of dried leaves were made and the qualitative and quantitative analysis of the main polyphenolic compounds in 50% methanol extracts by high-performance liquid chromatography. In addition, the content of major polyphenolic compounds in aqueous infusions was determined. Based on the results obtained, it was found that mint teas difer significantly from each other. It was observed that leaf teas have higher quality than teas in bags.Ziele mięty, powszechnie stosowane w medycynie tradycyjnej, spożywane jest głównie w postaci herbatek. Wykorzystanie mięty w medycynie ludowej jest związane z jej działaniem przeciwutleniającym, przeciwbakteryjnym, hipoalergicznym i immunomodulacyjnym, a także korzystnym dla przewodu pokarmowego. Właściwościami prozdrowotnymi charakteryzują się zarówno ziele, jak i olejek [1, 2]. Jest to doskonały środek żółciopędny, słabo rozkurczowy, wiatropędny i pobudzający apetyt. Użyty do inhalacji przeciw nieżytowi oskrzeli, katarowi i zapaleniu gardła działa antyseptycznie [3]. Celem niniejszej pracy była ocena i porównanie wyróżników jakościowych wybranych herbatek miętowych pochodzących od różnych producentów. Badaniom poddano 19 herbatek ziołowych, saszetkowanych i niesaszetkowanych,z mięty pieprzowej. Wykonano pomiary barwy suszów, a także poddano analizie jakościowej i ilościowej zawartość głównych związków polifenolowych w wyciągach metanolowo-wodnych metodą wysokosprawnej chromatograi cieczowej HPLC. Również w naparach wodnych z mięty pieprzowej oznaczono zawartość głównych związków polifenolowych. Na podstawie otrzymanych wyników stwierdzono, że susze ziołowe pochodzące od różnych producentów różnią się znacząco między sobą. Różnice w zawartości kwasu rozmarynowego były kilkukrotne, a eriocytrynyi pochodnych luteoliny nawet kilkudziesięciokrotne. Zaobserwowano, iż produkty niesaszetkowane charakteryzują się wyższymi wartościami wyróżników jakości niż produkty pakowane w saszetki

An Investigation into the Relation between the Technique of Movement and Overload in Step Aerobics

The aim of this research was to determine the features of a step workout technique which may be related to motor system overloading in step aerobics. Subjects participating in the research were instructors (n=15) and students (n=15) without any prior experience in step aerobics. Kinematic and kinetic data was collected with the use of the BTS SMART system comprised of 6 calibrated video cameras and two Kistler force plates. The subjects’ task was to perform basic steps. The following variables were analyzed: vertical, anteroposterior, and mediolateral ground reaction forces; foot flexion and abduction and adduction angles; knee joint flexion angle; and trunk flexion angle in the sagittal plane. The angle of a foot adduction recorded for the instructors was significantly smaller than that of the students. The knee joint angle while stepping up was significantly higher for the instructors compared to that for the students. Our research confirmed that foot dorsal flexion and adduction performed while stepping up increased load on the ankle joint. Both small and large angles of knee flexion while stepping up and down resulted in knee joint injuries. A small trunk flexion angle in the entire cycle of step workout shut down dorsal muscles, which stopped suppressing the load put on the spine

Fermented unripe cornelian cherry as a functional food

Consumer trends are changing due to the increasing awareness of the link between diet and health. The largest segment of the functional food market comprises foods fortified with probiotics, prebiotics and synbiotics. Fruits already containing high levels of beneficial substances can be reinforced with probiotic bacteria that can bring about additional health promoting features. Cornelian cherry (Cornus mas L.) fruits are rich sources of polyphenols and iridoids, valuable for fresh consumption or processing. Unripe fruits is manufactured by Arboretum in Bolestraszyce as a traditional product. The aim of this work was to evaluate the probiotic strains in order to determine their potential in the development of new starter cultures for functional food – green fermented cornelian cherry

Clinical course and outcome of SARS-CoV-2 infection in multiple sclerosis patients treated with disease-modifying therapies — the Polish experience

Introduction. The aim of this study was to report the course and outcome of SARS-CoV-2 infection in multiple sclerosis (MS) patients treated with disease-modifying therapies (DMTs) in Poland. A major concern for neurologists worldwide is the course and outcome of SARS-CoV-2 infection in patients with MS treated with different DMTs. Although initial studies do not suggest an unfavourable course of infection in this group of patients, the data is limited.Materials and methods. This study included 396 MS patients treated with DMTs and confirmed SARS-CoV-2 infection from 28 Polish MS centres. Information concerning patient demographics, comorbidities, clinical course of MS, current DMT use, as well as symptoms of SARS-CoV-2 infection, need for pharmacotherapy, oxygen therapy, and/or hospitalisation, and short-term outcomes was collected up to 30 January 2021. Additional data about COVID-19 cases in the general population in Poland was obtained from official reports of the Polish Ministry of Health.Results. There were 114 males (28.8%) and 282 females (71.2%). The median age was 39 years (IQR 13). The great majority of patients with MS exhibited relapsing-remitting course (372 patients; 93.9%). The median EDSS was 2 (SD 1.38), and the mean disease duration was 8.95 (IQR 8) years. Most of the MS patients were treated with dimethyl fumarate (164; 41.41%). Other DMTs were less frequently used: interferon beta (82; 20.70%), glatiramer acetate (42; 10.60%), natalizumab (35;8.84%), teriflunomide (25; 6.31%), ocrelizumab (20; 5.05%), fingolimod (16; 4.04), cladribine (5; 1.26%), mitoxantrone (3; 0.76%), ozanimod (3; 0.76%), and alemtuzumab (1; 0.25%). The overall hospitalisation rate due to COVID-19 in the cohort was 6.81% (27 patients). Only one patient (0.3%) died due to SARS-CoV-2 infection, and three (0.76%) patients were treated with mechanical ventilation; 106 (26.8%) patients had at least one comorbid condition. There were no significant differences in the severity of SARS-CoV-2 infection regarding patient age, duration of the disease, degree of disability (EDSS), lymphocyte count, or type of DMT used.Conclusions and clinical implications. Most MS patients included in this study had a favourable course of SARS-CoV-2 infection. The hospitalisation rate and the mortality rate were not higher in the MS cohort compared to the general Polish population. Continued multicentre data collection is needed to increase the understanding of SARS-CoV-2 infection impact on the course of MS in patients treated with DMTs

Identification of Iridoids in Edible Honeysuckle Berries (Lonicera caerulea L. var. kamtschatica Sevast.) by UPLC-ESI-qTOF-MS/MS

Iridoid profiles of honeysuckle berry were studied. Compounds were identified by ultra-performance liquid chromatography coupled with electrospray ionization mass spectrometry UPLC-ESI-qTOF-MS/MS in positive and negative ions mode. The MS fragmentation pathways of detected iridoid glycosides were also studied in both modes. In the negative ESI mass spectra, iridoids with a methyl ester or lactone structure have preferentially produced adduct [M + HCOOH − H]− ions. However, protonated ions of molecular fragments, which were released by glycosidic bond cleavage and following fragmentation of aglycone rings, were more usable for iridoid structure analysis. In addition, the neutral losses of H2O, CO, CO2, CH3OH, acetylene, ethenone and cyclopropynone have provided data confirming the presence of functional substituents in the aglycone. Among the 13 iridoids, 11 were identified in honeysuckle berries for the first time: pentosides of loganic acid (two isomers), pentosides of loganin (three isomers), pentosyl sweroside, and additionally 7-epi-loganic acid, 7-epi-loganin, sweroside, secologanin, and secoxyloganin. The five pentoside derivatives of loganic acid and loganin have not been previously detected in the analyzed species. Honeysuckle berries are a source of iridoids with different structures, compounds that are rarely present in fruits