spike jump biomechanics in male versus female elite volleyball players

ABSTRACTThere are well-known biological differences between women and men, especially in technical-coordinative variations that contribute to sex differences in performance of complex movements lik..

OBESITY AND METABOLIC SYNDROME IN CHILDREN AND YOUTH: A HEALTH RISK WE CANNOT AFFORD

Ample observational and empirical evidence has been provided that indicates that childhood metabolic syndrome risk factors inevitably lead to significantly more profound health risk factors of developing potent adulthood metabolic syndrome. Much of these data has been provided from medical, nutritional, health, pediatric, physical education and associated communities. Perhaps the most visible and observable health risk factor among children (here referred to as youth) is the childhood obesity. Childhood obesity has reached epidemic proportions in western industrialized countries and is also becoming significantly more prevalent in Slovenia. The youth inactivity is attributed directly to epidemic and perhaps exponential occurrence of obesity in pediatric and youth populations. The symptoms and signs of metabolic syndrome have previously been attributed mostly to the adult population; however, similar observations have been identified and observed in young and very young segment of population. The typical risk factors of metabolic syndrome in youth, in adolescents, and in adulthood have been commonly identified to be: stress, overweight and obesity, sedentary life cycle, aging, diabetes mellitus, coronary heart disease, lipodystrophy and several others. This presentation will review and address several well known risk factors of developing metabolic syndrome in young years that directly contributes to adult obesity and are exhibited in significantly higher rates of hypertension, dyslipidemias, and insulin resistance, which are all risk factors for coronary heart disease, the leading cause of death in North America and may also apply to Slovenia. Many of these risk factors are modifiable (nutrition, smoking, sedentary life style, vigorous physical activity, reduction in TV and computer game times, etc.) with specific emphasis on very young, young, adolescents and profound consequences for adulthood. Several recommendations will be proposed that may contribute to reduction of health risk factors among youth. The references have been generated from scientific literature and available information from various data bases in the United States, Center for Disease Control, National Institutes of Health, World Health Organization and several other relevant sources. These data and facts are very relevant to Slovenia because the inevitable truth is that these risk factors are "creeping up" into Slovenian society and it is my hope that you will be proactive and address these issues and act proactively rather than just stand by and observe the decline of health, especially among youth that will result in very costly financial burden of Slovenia for many years and decades to come

HEART RATE, MOOD STATES, AND RATING OF PERCEIVED EXERTION AMONG ELDERLY SUBJECTS DURING 3.5 HOURS OF RECREATIONAL ALPINE SKIING

A decline in physiological functioning and mental wellbeing is common with advancing age. However, these changes may vary among elderly individuals. Physical activity and the response of the elderly to exercise during recreational activities, i.e., recreational alpine skiing, may serve as a catalyst for the improvement of wellbeing and general health. Purpose: The aim of the study was to assess the heart rate (HR) response modulations in a group of elderly recreational alpine skiers during 3.5h of skiing. In addition, each group's perceived responses of mood state (MS) and rating of perceived exertion (RPE) were collected to determine possible contributions to changes in wellbeing as a result of recreational skiing. Methods: Forty-nine healthy elderly participants (mean age: 63±6 yrs, weight: 75.4+13.1 kg, height: 170.5+9.1 cm, BMI: 26+3.2) with at least basic alpine skiing ability participated in a 3.5h ski test. GPS data (GPS Garmin Forerunner 301) were used to monitor altitude and HR and were recorded continuously during the 3.5h of skiing. During skiing, participants were asked at three different times to report RPE and MS. Results: The time spent on the lift during the 3.5h skiing ranged from 21-58% followed by recovery breaks of 17-53% and time spent in downhill skiing ranged from 12-40%. Participants completed 9-23 downhill runs in 3.5h. Average intensities during 3.5 h downhill runs for over 80% of the group were between 50-80% of maximal heart rate (HRmax) (220-age). Peak heart rate (HRpeak) values during downhill runs for 35% of the group were between 60-70% of HRmax. Statistical analysis revealed numerous significant differences between RPE and MS values for the three different sampling times. The MS in general remained positive and even increased in the categories of happiness and sociability despite an increase in fatigue. Conclusion: The results of this study suggest that the duration and intensity of skiing was appropriate and yielded immediate positive psychological effects on the elderly subjects. Furthermore, recreational alpine skiing has a positive effect on MS ratings reflecting wellbeing, while generating age-appropriate moderate RPE values in elderly alpine skiers

KINEMATIC DESCRIPTION OF ELITE VS. LOW LEVEL PLAYERS IN TEAM-HANDBALL JUMP THROW

The jump throw is the most applied throwing technique in team- handball (Wagner et al., 2008); however, a comprehensive analysis of 3D-kinematics of the team-handball jump throw is lacking. Therefore, the purpose of our study was: 1) to measure differences in ball release speed in team- handball jump throw and anthropometric parameters between groups of different levels of performance and (2) to analyze upper body 3D-kinematics (flexion/extension and rotation) to determine significant differences between these groups. Three-dimensional kinematic data was analyzed via the Vicon MX 13 motion capturing system (Vicon Peak, Oxford, UK) from 26 male team-handball players of different performance levels (mean age: 21.2 ± 5.0 years). The participants were instructed to throw the ball (IHF Size 3) onto a target at 8 m distance, and to hit the center of a square of 1 × 1 m at about eye level (1.75 m), with maximum ball release speed. Significant differences between elite vs. low level players were found in the ball release speed (p < 0.001), body height (p < 0.05), body weight (p < 0.05), maximal trunk internal rotation (p < 0.05), trunk flexion (p < 0.01) and forearm pronation (p < 0.05) as well as trunk flexion (p < 0.05) and shoulder internal rotation (p < 0.001) angular velocity at ball release. Results of our study suggest that team-handball players who were taller and of greater body weight have the ability to achieve a higher ball release speed in the jump throw, and that an increase in trunk flexion and rotation angular velocity improve the performance in team-handball jump throw that should result in an increase of ball release speed

Journal of Sports Science and Medicine / Performance and kinematics of various throwing techniques in team-handball

PURPOSE: The aims of the present study were: (1) to compare the differences in the ball release speed and throwing accuracy between the ABOVE and SIDE throw; (2) to analyze kinematic differences of these two throwing techniques; and (3) to give practical applications to team handball coaches and players. METHODS: Ball release speed, throwing accuracy, and kinematics were measured via the Vicon MX 13 (Vicon Peak, Oxford, UK) from 12 male elite right-handed team handball players. RESULTS: Results of our study suggest that the two throwing techniques differ significantly (P < .0073) in the angles and/or angular velocities of the trunk (flexion, left tilt and rotation) and shoulder (flexion and abduction) of the throwing arm that result in a significantly different ball release speed (1.4 0.8 m/s; P < .001) and that throwing accuracy was not significantly different. CONCLUSION: Our results indicated that the different position of the hand at ball release of the ABOVE and SIDE throws is primarily caused by different trunk flexion and tilt angles that lead to differences in ball release speed but not in throwing accuracy, and that the participants try to move their throwing arm similarly in both throwing technique

Influence of cigarette smoking on synthesis of eicosanoids, isoprostanes and lipoxygenase metabolites in apical periodontitis

Arachidonic acid (AA) is metabolized to eicosanoids and isoprostanes (IPs) via different pathways. The presence of granuloma in apical periodontitis (AP) is linked with inflammation and the synthesis of metabolites of AA. We investigated the conversion rate of 14C labelled arachidonic acid (14C-AA), the lipoxygenases (LOX) products and the endogenous synthesis of eicosanoids and IPs in extracted granuloma. Furthermore, we assessed if there are markers for bone destruction and the influence of cigarette smoking. Conclusions: Our data demonstrate that in smokers with granuloma due to AP products of lipid peroxidation as 8-iso-PGF2α and products of the LOX-pathway are increased at the expense of cyclooxygenase products. The size of granuloma did not influence the amount of synthesized eicosanoids, IPs or LOX-metabolites out of 14C-AA whereas cigarette smoking was a significantly influencing and modifiable risk factor