Quality of Life and Physical Activity of Persons with Spinal Cord Injury.

The higher quality of life of people with spinal cord injury is closely related with their reintegration into the social environment. Social reintegration is a demanding and complex process, requiring individuals to become active again and acquire age-, gender-, and culture-appropriate roles and social status. It also involves independence and productive behavior as part of multiple interpersonal relationships with family, friends, and others. In order to establish whether individuals with spinal cord injury who are physically active subjectively rate their quality of life to be higher compared to those who are not, sixty-two respondents from Slovenia with spinal cord injury were interviewed. Thirty-one of them were physically active, and 31 were not. The level of injury of the responders was from Th6-Th12. The participants gave the highest assessments to their interpersonal relationships, and the lowest to their satisfaction with material prosperity. Data comparison showed that subjective estimates in all areas of quality of life are higher in respondents who were involved in physical activity after their injury. The results may encourage persons with spinal cord injury to participate more often in sports programs, and also encourage others to do so.

Physical Activity and Quality of Life in Hemodialysis Patients and Healthy Controls: A Cross-Sectional Study.

Hemodialysis (HD) patients have lower functional abilities compared to healthy people, and this is associated with lower physical activity in everyday life. This may affect their quality of life, but research on this topic is limited. Therefore, the present study aimed to determine the relationship between habitual physical activity and quality of life in HD patients and healthy controls. Ninety-three HD patients and 140 controls participated in the study. Quality of life was assessed using a 36-item medical outcomes study short-form health survey (SF-36). Human Activity Profile (HAP) was used to assess habitual physical activity. The adjusted activity score (AAS) from HAP, age, gender, fat tissue index (FTI), lean tissue index (LTI), and Davies comorbidity score were analyzed as possible predictors of the Physical Component Summary (PCS) of the SF-36. Three sequential linear models were used to model PCS. In Model 1, PCS was regressed by gender and age; in Model 2 the LTI, FTI, and Davies comorbidity scores were added. Model 3 also included AAS. After controlling for age and gender (ModelHD 1: p = 0.056), LTI, FTI, and Davies comorbidity score effects (ModelHD 2: p = 0.181), the AAS accounted for 32% of the variation in PCS of HD patients (ModelHD 3: p < 0.001). Consequently, the PCS of HD patients would increase by 0.431 points if the AAS increased by one point. However, in healthy controls, AAS had a lower impact than in the HD sample (B = 0.359 vs. 0.431), while the corresponding effects of age and gender (ModelH 1: p < 0.001), LTI, FTI, and Davies comorbidity score (ModelH 2: p < 0.001) were adjusted for. The proportion of variation in PCS attributed to AAS was 14.9% (ModelH 3: p < 0.001). The current study results showed that physical activity in everyday life as measured by the HAP questionnaire is associated to a higher degree with the quality of life of HD patients than in healthy subjects. Routine physical activity programs are therefore highly justified, and the nephrology community should play a leading role in this effort.

Split-Step Timing of Professional and Junior Tennis Players.

The purpose of the study was to determine the timing of a split-step in three categories of tennis players in four groups of strokes. Subjects were divided into three groups: male and female junior, and male professional tennis players. During two tournaments, all matches were recorded with two fixed video cameras. For every stroke, the timing of the split-step between the opponent's impact point when hitting the ball and the player's split-step was measured. A two-way analysis of variance (ANOVA) was used to determine the differences between groups of strokes, players and the interaction Player x Stroke Group. A Tukey post-hoc test was employed to determine specific differences. The results revealed differences between players in detecting the opponent's movement, stroke and ball flight, which were reflected in different split-step timings. Each tennis player has his/her own timing mechanism which they adapt to various game situations. Response times differ significantly depending on the game situation. On average, they are the lowest in the serve, and then gradually rise from the return of the serve to baseline game, reaching the highest values in specific game situations. Players react faster in the first serve than in the second one and in the return of the serve, the response times are lower after the return of the second serve.

Differences in Movement Speed Before and After a Split-Step Between Professional and Junior Tennis Players.

This study investigated tennis players' speed before, during and after the split-step, deceleration before and acceleration after the split-step in four different stroke groups in three age categories. Seven male professional, eleven male and ten female junior tennis players were recorded with video cameras at official tournaments. Using the SAGIT system, we gathered data on 8,545 split-steps. Tennis players performed a split-step in 82.9% of cases. A tennis player's speed, deceleration and acceleration were measured 0.2 s before and after the split-step. Differences between categories and stroke groups for each of the five variables were analyzed with a two-way ANOVA. The differences between the groups of players were generally much higher in the speed before, during and after the split-step than in the deceleration before and acceleration after the split-step. Most of these differences were observed between the various stroke groups. These results suggest that players use three types of movement while performing a split-step. In the first type, which is typical of serving and returning, the speed before, during and after the split-step is lower (0.55 to 1.2 m/s). The second type of movement is characteristic of baseline strokes where tennis players achieve higher speed than in the first type (0.7 to 1.66 m/s). The third type occurs in strokes where a tennis player is moving or already at the net (0.78 to 1.9 m/s). Movement in tennis is an area that requires constant development in terms of designing and upgrading movement patterns, increasing speed and practice in specific game situations.

Lateral asymmetry in upper and lower limb bioelectrical impedance analysis in youth tennis players / Análisis de asimetría lateral de impedancia bioeléctrica de miembros superiores e inferiores en jugadores jóvenes de tenis

Tennis is a sport that requires asymmetric movements of dominat limbs and may lead to an asymmetric distribution of muscle mass. The main aim of the presented study was to determine the volume and degree of lateral asymmetry of the upper and lower limbs in youth tennis players using a bioelectrical impedance analysis. T-test was applied to find differences between the dominant and non-dominant arm and the right and left leg and thigh in four age categories. There were no significant differences between the right and left leg lean mass in the 12 and under, 14 and under and 16 and under age groups, but there were significant differences between the dominant and non-dominant arm lean mass and arm circumferences in all four age groups. All young tennis players had greater lean mass and arm circumferences of the dominant limb. Tennis players in the 18 and under group had higher average values of right leg lean mass and the differences are statistically significant. There were significant differences between right and left thigh circumferences in all age groups. Findings show that it is possible with such a simple, non-invasive and quick procedure as bioelectrical impedance to determine asymmetry in tennis players.

El tenis es un deporte que requiere movimientos asimétricos de los miembros dominantes y puede conducir a una distribución asimétrica de la masa muscular. El objetivo fue determinar el volumen y grado de asimetría lateral de los miembros superiores e inferiores en tenistas juveniles utilizando un análisis de impedancia bioeléctrica. Se aplicó la prueba T para encontrar diferencias entre el brazo dominante y no dominante y las piernas y muslos derecho e izquierdo en cuatro categorías de edad. No hubo diferencias significativas en la masa magra de las piernas derecha e izquierda en los grupos de edad: 12 y menor, 14 y menor, y 16 y menor. Sin embargo, hubo diferencias significativas en la masa magra de las circunferencias de los brazos dominante y no dominante en los cuatro grupos de edad. Todos los jugadores jóvenes de tenis tenían mayor masa magra en las circunferencias de los brazos del miembro dominante. Los jugadores de tenis en el grupo de 18 años y menor, tenían valores medios más altos de masa magra de la pierna derecha, con diferencias estadísticamente significativas. No hubo diferencias significativas entre las circunferencias de los muslos derecho e izquierdo en todos los grupos de edad. Los resultados muestran que es posible determinar con un procedimiento simple no invasivo y rápido, como la impedancia bioeléctrica, la asimetría en jugadores de tenis.

Relationship of Speed, Agility, Neuromuscular Power, and Selected Anthropometrical Variables and Performance Results of Male and Female Junior Tennis Players.

The aim of the study was to analyses the relation between the selected speed, agility, and neuromuscular power test items. The sample of subjects consisted of 154 male and 152 female young tennis players. Using six motor and three anthropometrical tests we investigate differences between males and females and between two age categories. Finally, we analyzed the relation between motor and anthropometrical tests and a player's tennis performance. The correlation between the two agility test items and 5-m sprint is very large in male players, while only moderate with 20-m sprint in female category. Male tennis players have higher correlations between speed test items and neuromuscular test items. The speed test item (5-m sprint) has large correlation with a player's tennis performance. One-way analysis of variance results indicated that young male tennis players performed significantly better than females in all motor test items. Significant differences between genders have not been revealed only in the body mass index. Differences between the males aged 18& under and 16& under have been noted as significant in all test items, except the vertical jump, while differences between the females have been noted as significant in three anthropometrical tests, quarter jump, and the fan-drill test. Regression analyses have shown that the system of prediction variables explains a relatively small part of variance (46%--males and 40%--females). In both genders, it has been revealed that test items measuring speed significantly influence a player's tennis performance.

Differences in physical fitness among young tennis players in between 1992 and 2008.

The aim of this study was to find a trend of changes for selected anthropometric characteristics and motor abilities of young male and female tennis players of three different age groups. Trends were observed in the periods between 1992, 2000 and 2008. In addition, a comparison of results of tennis players and school pupils was included. The sample of subjects were selections of young tennis players and of primary and secondary schools pupils (boys and girls) divided into three age groups (12- to 13-year-olds, 14- to 15-year-olds, and 16- to 17-year-olds). Fitness tests items (backwards obstacle course, forward bend on the bench, 20-second hand-tapping, 60-second sit-ups) and three anthropometric measurements (body height, body weight, BMI) were included in this study. The analysis of trends for different periods of measurement in male and female tennis players revealed an increase in some test items and a decrease in others. In the majority of observed fitness test items, young tennis players performed better than their school peers, indicating the positive effects of training and an appropriate selection process of tennis players. Male and female tennis players were taller than the school pupils, and body height values in both groups increased from 1992 to 2008. The body weight and BMI values for male and female tennis players, and male and female pupils in all three age groups have been constantly increasing.

Secular Trends in Body Dimensions among Young Tennis Players from 1992 to 2008 / Tendencias Seculares en las Dimensiones Corporales entre Tenistas Jóvenes desde 1992 hasta 2008

Several studies have examined both physical characteristics and fitness of children and youth. The aim of the study was first, to find the tendency of changes in selected morphological characteristics of young male and female tennis players of various ages in the periods 1992-2000-2008; and second, to find the changes in selected variables of young tennis players and to compare them with the results of boys and girls of same age from normal school population. Sample of variables included body height, body weight and body mass index (BMI). Multivariate analysis of variance revealed statistically significant differences in all main factors (group, age, gender and period) and additionally in interactions group*period, group*gender and age*gender. Univariate analysis of variance revealed statistically significant differences in body height and BMI between the groups of tennis players and the same age school population for both sexes and between three age groups (12-13 years, 14-15 years, 16-17 years) for body height, body weight and BMI. Differences between the sexes indicate statistically significant differences only in variables body height and weight. Changes in the observed morphological characteristics point to the increase in body height, body weight and BMI values in both school population and young tennis players.

Diversos estudios han examinado las características y estado físico de niños y jóvenes. El objetivo de este estudio fue encontrar la tendencia de los cambios para determinadas características morfológicas de jóvenes tenistas (hombres y mujeres) de distintas edades, en los períodos 1992-2000-2008. Además, encontrar cambios en las variables seleccionadas de jugadores de tenis jóvenes y compararlos con los resultados de niños y niñas de la misma edad en la población escolar normal. Las variables de la muestra incluyeron altura y peso corporal e índice de masa corporal (IMC). El análisis multivariado de varianza reveló diferencias estadísticamente significativas en todos los factores principales (grupo, edad, sexo y periodo) y, además, en las interacciones de grupo-período, grupo-edad y grupo-sexo. El análisis univariado de varianza reveló diferencias estadísticamente significativas en la altura corporal e IMC entre los grupos de jugadores de tenis y la misma población en edad escolar para ambos sexos y entre los tres grupos de edad (12-13 años, 14-15 años, 16-17 años) para altura y peso corporal e IMC. Las comparación entre sexos indican diferencias estadísticamente significativas sólo en las variables altura y peso corporal. Los cambios en las características morfológicas observadas señalan un aumento de la altura y peso corporal e IMC tanto en la población escolar como en los jóvenes jugadores de tenis.