Introduction. The aim of the study was to examine differences in muscle strength and topography between judoists, boxers, and taekwondo athletes. Material and methods. Thirteen judoists, 6 boxers, and 7 taekwondo athletes took part in the study. The maximal joint torque of the flexors and extensors of the elbow, shoulder, hip, knee, and trunk were measured under isometric conditions. Results. The absolute and relative joint torque was similar in the three groups except for the absolute strength of the right flexor of the shoulder between the boxers and the taekwondo athletes and judoists (p < 0.01). The sums of the relative joint torque and topography of the joint torque of the right and left upper extremity, lower extremity, and trunk were similar in the groups. A significant difference was observed in the topography of the joint torque of the right upper and lower extremity and of the trunk between the boxers and the taekwondo athletes and judoists (p < 0.01). The topography of the joint torque of the flexors and extensors of the right shoulder was significantly different between the boxers and the taekwondo athletes and judoists (p < 0.01). Conclusions. In martial arts, the training undergone by the athletes and their participation in competitions can be expected to affect their strength. The joint torque was similar in the combat groups examined in this study. Judoists and taekwondo athletes did not differ in muscle topography. Boxers differed from the other two groups only in the contribution of the flexors and extensors of the right shoulder, in the sum of the torques of the right upper and lower limb, and the sum of the torques of the trunk. These results may be due to the characteristics of the discipline and the training methods used.
Study aim: The aim of the study was to examine biomechanical characteristics of taekwondo athletes comparing kicks and punches with laboratory tests of muscle strength and power. Material and methods: Six male taekwondo athletes participated in this study. Measurements of maximal punching with the rear hand (hook and straight punches) and kicking (Apdolio and Dwit Chagi) force were performed on a boxing dynamometer. Also, the following laboratory tests were performed: jump height and power output in counter movement jump (CMJ) and spike jump (SPJ), muscle strength for 10 muscle groups and force-velocity (F-v) relationship. Results: Mean maximal straight and hook punching forces were 1659.2 ± 254.2 N and 1843.8 ± 453.3 N, respectively. Maximal Apdolio rear leg, Apdolio lead leg and Dwit Chagi rear leg kicking forces were 3541.3 ± 1130.3 N, 3205.3 ± 965.1 N and 3568.0 ± 1306.0 N, respectively. The heights of jumps were 0.501 ± 0.040 m (CMJ) and 0.554 ± 0.034 m (SPJ). A strong correlation between the maximal force of a punch and maximal joint torques was observed. Conclusions: The values of kicking forces developed in a simulated fight were lower than the forces developed in the test of individual kicks. Strong relationships were observed between leg power developed in the SPJ and force of individual Apdolio kicks performed with the lead (r = 0.87, p < 0.05) and rear leg (r = 0.74). Based on these findings, it was concluded that maximal joint torques and height of the SPJ could be used as a proxy of kicking force.
Study aim: The aim of the study was to examine the differences in physical fitness between deaf female soccer players and their deaf peers who did not practise any sport.
Material and methods: The research involved 13 deaf female soccer players and 16 deaf untrained girls. Physical fitness was assessed by a jump test and the Eurofit test. In the jump test, each participant performed an akimbo counter-movement jump (ACMJ), a counter-movement jump (CMJ) and a spike jump (SPJ) on a force plate. The following trials of the Eurofit test were performed: flexibility – sit-and-reach; static strength – hand grip; functional strength – bent arm hang (arm and shoulder muscular endurance); explosive strength – standing broad jump; and trunk strength – sit-ups (abdominal muscular endurance).
Results: Soccer players jumped significantly higher than untrained females in the ACMJ, CMJ, and SPJ, and developed significantly higher power of the CMJ. Relative power developed in the ACMJ and SPJ did not differ between the examined groups. Soccer players were physically fitter than girls who did not play any sport. Significant differences between the groups were observed for all measured trials except for the bent arm hang.
Conclusions: Hearing loss does not significantly determine the physical development or physical fitness of deaf people. Playing sports improves the physical fitness of deaf people in comparison with untrained deaf people.
Changes in physiological and biomechanical variables in women practicing the Power Yoga system
Study aim: To investigate changes in selected indices of anaerobic capacity, the ability to maintain body balance and the height of elevating body's centre of mass, and maximum power output in lower limbs during countermovement jump (CMJ) after 6 months of participation in yoga classes in Ashtanga Vinyasa system (Power Yoga).
Material and methods: The study included 24 untrained women who volunteered to participate in a half-year experiment. The analysis focused on 12 women who participated in the classes until the experiment ended. The Wingate test was used to evaluate anaerobic capacity. In order to measure the functional state of vestibular organ the authors used a stabilographic method. Measurements of power output in the lower limbs and the height of elevation of the centre of mass in CMJ jumps were carried out using a dynamometric platform.
Results: The 6 months of training in the Power Yoga system considerably improved the height of CMJ jumps from 0.276 ± 0.048 m to 0.308 ± 0.038 m (p<0.05). These changes were not accompanied by significant increases in maximum power output (1286 ± 200 W and 1327 ± 2134 W before and after, respectively; p>0.05).
Conclusions: Practicing Power Yoga does not induce changes in the anaerobic capacity and the functional state of the vestibular organ in women.
Study aim: The aim of the study was to determine the weekly energy expenditure measuring MET/min/week based on data collected through the Canada Fitness Survey (CFS), according to the classification used in the International Physical Activity Questionnaire (IPAQ), and to verify the adopted method to assess the level of physical activity in students of physical education.
Material and methods: The study involved 116 female students (21.1 ± 1.6) and 276 male students (21.2 ± 1.7), studying Physical Education at Kazimierz Wielki University. Physical activity (PA) of respondents assessed using the Canada Fitness Survey was converted to energy expenditure in MET/min/week using the criteria established in the IPAQ. Body composition was assessed according to bioelectrical impedance.
Results: A significantly smaller fat fraction was observed in the group of students with high physical activity (PA) (p < 0.01). In women, there was a significant relation between FAT% and all analysed characteristics of physical activity: total physical activity (TPA) – 0.274, vigorous intensity (VI) – 0.216, number of days spent on physical activity (DTPA) – 0.199 and number of days spent on vigorous intensity (DVI) – 0.202 (p < 0.05). In men, a significant relation was found between all the analysed tissue components and the adopted variables of PA (FAT% vs. TPA – 0.145, VI – 0.203, DTPA – 0.187; FATkg vs. TPA – 0.123, VI – 0.186, DTPA – 0.178; FATkg vs. DVI – 0.131). BMI significantly correlated with VI (–0.162) and DVI (–0.140), p < 0.05.
Conclusions: Based on data collected using the CFS on the type and frequency of PA during a week, we can determine the level of activity in a measurable way, using the IPAQ classification. There is a significant relationship between thus determined physical activity levels and body composition in both women and men, which proves the accuracy of the adopted method of converting weekly energy expenditure to MET/min/week.
Study aim: Systematic physical activity is an effective preventive measure that supports the preservation of physical health and psychological health. Three expressions employed that relate to the work carried out with MET-min/week as a measure of the level of total physical activity are intense activity, moderate activity, and walking. These were applied to students studying Physical Education. In the process, those who failed to meet the requirements for the ‘sufficient’ level according to IPAQ criteria and as recommended by the WHO were identified.
Material and methods: Research was conducted amongst 146 students: 50 from Charles University (CU) and 96 from the University of Physical Education in Warsaw (UPE). The total physical activity of students was determined according to the accepted standards (IPAQ). WHO recommendations concerning physical activity per week were converted into MET-min/week used by IPAQ as follows: physical activity needs to achieve at least 1200 MET-min/week to increase its effect on health.
Results: The study of Physical Education students at CU shows that they were significantly more active than their counterparts at UPE. Total physical activity per week as measured by IPAQ at CU was 9525.2 ± 4275.9 for men and 10964.3 ± 4092.0 MET-min/week for women. At UPE, this was 4034.3 ± 2617.8 for men and 2469.8 ± 1721.2 MET-min/week for women. The difference in total levels of physical activity carried out by these students was found to depend largely upon their involvement in championship sports. Inclusion of WHO recommendations in the assessment of physical activity of students increased the proportion of individuals with low activity levels, particularly in the group of not-training students.
Conclusions: It is recommended either that the WHO criterion “of activity level for health” be added to the IPAQ classification, thus toughening the requirements of the moderate level of activity, or, alternatively, an additional threshold of completing at least 1200 MET-min/week be applied, with the recommendation that this is achieved on a regular basis.
Study aim: The aim of the present study was to determine a strength profile which characterizes young male athletes from different sports and to use the method of allometry to synthetically evaluate the muscular strength with respect to body mass.
Material and methods: The study included 85 men who practiced taekwondo (8 subjects), 20 judoists, 10 weightlifters, 35 canoeists and 12 speed skaters. Measurements of maximal muscle torques in 10 groups of flexors and extensors of the elbow, shoulder, hip, knee and trunk were carried out in a testing station for muscle torque measurements under static conditions. In order to determine the relationships between the body mass and muscle torques in each muscle group, the authors used a procedure of linear regression for the data expressed as logarithms. Hence, the allometric relationship scaled with body mass was obtained.
Results: The study demonstrated that the mean values of logarithms of maximal muscle torques are significantly different for the representatives of individual sports and they depend on the logarithm of body mass. The analysis of residuals was employed for the evaluation of maximal muscle torques. The highest strength profiles were observed in athletes who practice judo and the lowest in those who represented weightlifting and taekwondo.
Conclusion: The authors propose to use an allometric relationship which takes body mass into consideration during evaluation of strength in individual muscle groups, because the values of muscle torques are not in direct proportion to body mass and their mutual proportions change with an increase in body mass.
Study aim: The aim of this study was to determine the body composition and somatotype of untrained male students studying at Warsaw University of Technology in 2011, in order to create a current reference group for comparison, and to investigate the difference in body build of male judoists compared with the non-athlete group.
Materials and methods: Fifteen male judo athletes (age 18.6 ± 1.9 years, body height 177.4 ± 8.5 cm, body mass 80.3 ± 15.8 kg, training experience 10.0 ± 2.8) and 154 male untrained students of the Warsaw University of Technology (age 20.1 ± 0.9 years, body height 180.9 ± 7.2 cm, body mass 75.6 ± 10.9 kg) participated in the study. Somatotype was determined using the Heath- Carter method.
Results: The mean somatotype of the untrained students was 220.127.116.11, whilst that of the judo athletes was 18.104.22.168; the groups differed significantly in their mesomorphy and ectomorphy components. Significant differences between the groups were found in breadth of wrist, bicristal diameter and arm circumference (p < 0.05). The groups were also significantly different in body composition as estimated by BIA and anthropometric methods (p < 0.05).
Conclusion: The morphological characteristics of the judo athletes differed from those of the untrained men. The somatic profile of body build for athletes in this sport seems to be optimal for achieving high results, the somatotype not having changed since the 1990s.
The aim of this study was to evaluate the relationship of a wide range of anthropometric parameters with BMD in normal-weight women: handball players and healthy untrained students. Thirteen former female handball players, (age 21.2±0.9 years, body mass 64.2±6.1 kg, training experience 6.7±2.4 years) and 51 randomly selected untrained students (age 20.6±1.2 years, body mass 58.1±6.8 kg), were examined. The anthropometric measurements included 16 variables. BMD was measured on the radius of the non-dominant hand at distal and proximal points with dual-energy X-ray absorptiometry (DXA), using a Norland pDEXA densitometer. Relationships between BMD and anthropometric variables were assessed in 64 normal-weight women (BMI≥18.5 and ≤ 24.99 kg/m2), by calculating Pearson’s linear correlation coefficient. We found a significant positive relationship between bone mass characteristics and biacromial breadth (0.30-0.53), calf (0.28-0.47) and arm (0.27-0.42) girth corrected, and lean body mass (LBM) (kg) (0.38-0.61) and (%) (0,27) in the group of normal-weight women. The student groups were significantly different (analysis of variance with Scheffé post hoc test, p<0.001) in BMD, bone mineral content (BMC) and Z-score at both measured points. The former handball players were also characterized by higher body mass and LBM (kg), as well as corrected body girths and biacromial breadth (p<0.001), compared to untrained students. The groups did not differ significantly in body height or total fat. The morphological profile of the female handball players is conducive to BMD. Skeletal characteristics and muscle tissue had a significant beneficial effect on bone mineral characteristics in young women with normal weight.
Somatotype Variables Related to Muscle Torque and Power in Judoists
The purpose of this study was to examine the relationship between somatotype, muscle torque and power output in judoists. Thirteen judoists (age 18.4±3.1 years, body height 178.6±8.2 cm, body mass 82.3±15.9 kg) volunteered to participate in this study. Somatotype was determined using the Heath-Carter method. Maximal muscle torques of elbow, shoulder, knee, hip and trunk flexors as well as extensors were measured under static conditions. Power outputs were measured in 5 maximal cycle ergometer exercise bouts, 10 s each, at increasing external loads equal to 2.5, 5.0, 7.5, 10.0 and 12.5% of body weight. The Pearson's correlation coefficients were calculated between all parameters. The mean somatotype of judoists was: 3.5-5.9-1.8 (values for endomorphy, mesomorphy and ectomorphy, respectively). The values (mean±SD) of sum of muscle torque of ten muscle groups (TOTAL) was 3702.2±862.9 N × m. The power output ranged from 393.2±79.4 to 1077.2±275.4 W. The values of sum of muscle torque of right and left upper extremities (SUE), sum of muscle torque of right and left lower extremities (SLE), sum of muscle torque of the trunk (ST) and TOTAL were significantly correlated with the mesomorphic component (0.68, 0.80, 0.71 and 0.78, respectively). The ectomorphic component correlated significantly with values of SUE, SLE, ST and TOTAL (-0.69, -0.81, -0.71 and -0.79, respectively). Power output was also strongly correlated with both mesomorphy (positively) and ectomorphy (negatively). The results indicated that the values of mesomorphic and ectomorphic somatotype components influence muscle torque and power output, thus body build could be an important factor affecting results in judo.