rss_2.0Biomedical Human Kinetics FeedSciendo RSS Feed for Biomedical Human Kinetics Human Kinetics 's Cover between clinical tests for gait and stability using biomechanical variables in the gait of institutionalized elderly subjects<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: This study aims to identify biomechanical gait variables explaining clinical test results in institutionalized elderly people.</p> <p><italic>Material and methods</italic>: Twenty-nine elderly (82.0 ± 6.3 years) residents in a nursing home were assessed. They were able to walk 10 meters without walking aids. First, the spontaneous gait was assessed using inertial measurement units in a 10-meter long corridor. Fifteen biomechanical gait variables were analyzed. Then, three clinical tests usually used in elderly subjects were applied: the Timed Up and Go (TUG) test, the Tinetti Scale and the Sit to Stand (STS) test. A correlation matrix using Pearson’s correlation coefficient between clinical and biomechanical variables was performed, obtaining a total of 45 potential correlations. A stepwise multiple linear regression analysis was then performed to determine the influence of each variable.</p> <p><italic>Results</italic>: TUG, Tinetti and STS were significantly correlated with similar biomechanical variables, including temporal, temporo-spatial and kinematic variables. Adults over 80 years old and women showed stronger correlations. Single support and ankle angle at takeoff were the two most important variables in stepwise regression analysis.</p> <p><italic>Conclusions</italic>: In institutionalized elderly subjects, clinical variables for gait and postural stability are correlated with the biomechanical gait variables, especially in women and adults aged over 80 years.</p> </abstract>ARTICLE2021-01-29T00:00:00.000+00:00How does the ski boot affect human gait and joint loading?<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: To investigate the effect of wearing ski boots on kinematic and kinetic parameters of lower limbs during gait. Furthermore, loads in lower limb joints were assessed using the musculoskeletal model.</p> <p><italic>Material and methods</italic>: The study examined 10 healthy women with shoe size 40 (EUR). Kinematic and kinetic data of walking in ski boots and barefoot were collected using a Vicon system and Kistler plates. A musculoskeletal model derived from AnyBody Modeling System was used to calculate joint reaction forces.</p> <p><italic>Results</italic>: Wearing ski boots caused the range of motion in the knee joint to be significantly smaller and the hip joint to be significantly larger. Muscle torques were significantly greater in walking in ski boots for the knee and hip joints. Wearing ski boots reduced the reaction forces in the lower limb joints by 18% for the ankle, 16% for the knee, and 39% for the hip.</p> <p><italic>Conclusions</italic>: Ski boot causes changes in the ranges of angles in the lower limb joints and increases muscle torques in the knee and hip joints but it does not increase the load on the joints. Walking in a ski boot is not destructive in terms of forces acting in the lower limb joints.</p> </abstract>ARTICLE2021-05-24T00:00:00.000+00:00Aerobic capacity and respiratory patterns are better in recreational basketball-engaged university students than age-matched untrained males<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: To asses and compare the aerobic capacity and respiratory parameters in recreational basketball-engaged university students with age-matched untrained young adults.</p> <p><italic>Material and methods</italic>: A total of 30 subjects were selected to took part in the study based on recreational-basketball activity level and were assigned to a basketball (BG: n = 15, age 22.86 ± 1.35 yrs., body height 185.07 ± 5.95 cm, body weight 81.21 ± 6.15 kg) and untrained group (UG: n = 15, age 22.60 ± 1.50 yrs., body height 181.53 ± 6.11 cm, body weight 76.89 ± 7.30 kg). Inspiratory vital capacity (IVC), forced expiration volume (FEV1), FEV1/IVC ratio, maximal oxygen consumption (VO<sub>2max</sub>), ventilatory threshold (VO<sub>2</sub>VT<sub>)</sub> and time to exhaustion, were measured in all subjects. Student T-test for independent Sample and Cohen’s <italic>d</italic> as the measure of the effect size were calculated.</p> <p><italic>Results</italic>: Recreational basketball-engaged students (EG) reached significantly greater IVC (t = 7.240, p &lt; 0.001, d = 1.854), FEV1 (t = 10.852, p &lt; 0.001, d = 2.834), FEV1/IVC ratio (t = 6.370, p &lt; 0.001, d = 3.920), maximal oxygen consumption (t = 9.039, p &lt; 0.001, d = 3.310), ventilatory threshold (t = 9.859, p &lt; 0.001, d = 3.607) and time to exhaustion (t = 12.361, p &lt; 0.001, d = 4.515) compared to UG.</p> <p><italic>Conclusions</italic>: Long-term exposure to recreational basketball leads to adaptive changes in aerobic and respiratory parameters in male university students.</p> </abstract>ARTICLE2021-03-23T00:00:00.000+00:00How combined aerobic training and pomegranate juice intake affect lipid profile? A clinical trial in men with type 2 diabetes<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: This study aimed to investigate the effect of aerobic training (AT) and pomegranate juice intake (PJI) on the lipid profile in men with type 2 diabetes.</p> <p><italic>Materials and methods</italic>: This randomized clinical trial was performed in middle-aged men (40–50 years old) with type 2 diabetes. Participants were randomly assigned into four groups: AT + PJI (n = 9); AT (n = 10); PJI (n = 9), and control (C) (n = 10). The AT program consisted of 60-75% of HR<sub>Max</sub>, 40-60 min/day, three days/wk for eight weeks. Participants in the PJI group consumed 240 ml of pomegranate juice (sugar or additive-free) daily for eight weeks. Lipid profile was measured at the beginning and end of the study. The data were analyzed through paired t-test and one-way analysis of variance, as well as Tukey’s post hoc test at the signification level of P&lt;0.05.</p> <p><italic>Results</italic>: AT + PJI, PJI, and AT groups demonstrated significant improvements in lipid profile compared to the C group. The results show that the AT + PJI group had significantly lower TC and LDL (p = 0.001 and p = 0.002, respectively), and significantly higher HDL (p = 0.023) compared with the PJI group. There was no significant difference between AT and PJI groups. Also, TG was significantly lower in AT+ PJI compare to the C group.</p> <p><italic>Conclusions</italic>: AT + PJI is more effective than AT or PJI alone in the improvement of lipid profile in patients with type 2 diabetes.</p> </abstract>ARTICLE2021-05-08T00:00:00.000+00:00Reliability of 3D measurement of pelvic and lower limb kinematics during two single leg landing tasks<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: Three-dimensional (3D) motion analysis is one of the available methods used to evaluate body kinematics. The aim of this study was to assess the intrarater reliability of measurement of pelvic and lower limb kinematics during two single leg landing tasks using 3D motion analysis.</p> <p><italic>Material and methods</italic>: 19 healthy volunteers (8 women, 11 men, age 23.1 ± 2.8 years, weight 70.7 ± 9.2 kg, height 174.8 ± 6.7 cm) performed five repeated single leg hurdle hops (SLHH) (30 cm height) and five single leg drop landings (SLDL) from a box (40 cm height) in one measurement session with a 15-minute break and after marker replacement with 3D assessment. The intraclass correlation coefficient (ICC), standard error of measurement (SEM), and the smallest detectable differences (SDD) were used to examine the reliability of kinematic parameters during the landing phase.</p> <p><italic>Results</italic>: The average intrarater ICC for SLHH was 0.92 (SEM = 1.69°, SDD 4.68°) and for SLDL was 0.96 (SEM = 0.81°, SDD = 2.26°). After marker replacement ICC decreased to an average value of 0.81 (SEM = 2.05°, SDD 5.68°) for SLHH and 0.82 (SEM = 2.36°, SDD 6.53°) for SLDL.</p> <p><italic>Conclusions</italic>: Using the 3D method to evaluate pelvis and lower limb kinematics during single leg landing in one measurement session is a high reliability method for most parameters. Marker replacement is one of the factors that reduce the reliability of measures. When applying the SEM and SDD values, which the present paper contains, it is worth mentioning that the obtained results are caused by measurement error or they are due to individual issues.</p> </abstract>ARTICLE2021-01-29T00:00:00.000+00:00Comparison of effect of aquatic interventions on cardiac modulation of obese young males in motion. A crossover trial<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: The study aimed to compare the effects of passive Watsu therapy and immersion on cardiac locomotor synchronization of obese young males.</p> <p><italic>Material and methods</italic>: Twenty-six volunteer obese males participated in this study (age 18.3 ± 0.32, BMI 36.9 ± 6.52). Heart rate variability parameters were recorded in different positions by the Polar H7 heart rate sensor and HRV+ software. Participants were assigned to two groups, randomly, in a single-blinded crossover design. Kubios HRV 2.2 and MATLAB were used to analyze the bio-signals. Statistical analysis was performed via t-test and ANOVA (analysis of variance) using SPSS. For the significance in results and group comparison, the paired t-test and the independent t-test were used respectively.</p> <p><italic>Results</italic>: Combined results indicated that Watsu therapy increased 3 HRV vertical position parameters and immersion increased 3 HRV non-locomotor parameters, significantly (p &lt; 0.05).</p> <p><italic>Conclusion</italic>: The findings show that Watsu and immersion improved the specific autonomic cardiac modulation. However, non-contact immersion seemed to provide better synchronization of cardiac control and locomotion. The close contact Watsu approach provided improvements in autonomic cardiac regulation. Collectively, these improvements suggest the combination of both therapies in maximizing the cardiac benefits sought by aquatic therapy programs.</p> </abstract>ARTICLE2021-01-27T00:00:00.000+00:00Body fatness in sedentary and active students with different body mass index<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: Numerous data have indicated that body fat stores undergo complicated regulation by genetic and environmental factors, including physical activity. However, the majority of studies did not take into account this aspect of lifestyle in proposed body fat limits. In this context it seems that a more precise and reliable classification of body fat is provided by the American Council on Exercise (ACE), which distinguishes individuals not only with respect to sex but also activity level.</p> <p><italic>Material and methods</italic>: A total of 793 students (312 sedentary and 481 active) volunteered to participate in the study. Among sedentary participants 147 were male and 165 female. Among active subjects 206 were male and 275 were female. Active subjects were engaged in different modes of physical activity according to the study program. In all participants body mass index (BMI) was calculated. In participants with BMI 18.5–24.9 and BMI ≥ 25 body fat was determined using four skinfold measurements. Thereafter participants were classified according to the percentage of body fat using ranges for males and females provided by the American Council on Exercise (ACE) (essential fat, athletes, fitness, average and obese fatness).</p> <p><italic>Results</italic>: None of the sedentary and active males with BMI 18.5–24.9 had high (obese) fat. In contrast, in sedentary males with BMI ≥ 25 16.4% were obese vs. 1.8% of obese active ones. In sedentary females BMI from 18.5 to 24.9 did not exclude obesity, which was found in 16.9% of participants. In sedentary females with BMI ≥ 25 most of the subjects (97.1%) were obese. In contrast, in active females with BMI ≥ 25 a similar percentage of participants had average and obese fat (53.3% and 46.7, respectively).</p> <p><italic>Discussion</italic>: Our study clearly demonstrated that BMI as a simple measure of body composition provides false information concerning true adiposity in physically active male and female students. A similar BMI did not exclude marked differences in the percentage of body fat in sedentary and active students.</p> </abstract>ARTICLE2021-01-29T00:00:00.000+00:00The effects of single-sex versus coeducational physical education on american junior high PE students’ physical activity levels and self-competence<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: To examine single-sex classes versus coeducational classes in 7<sup>th</sup> grade PE and the effect the setting had on physical activity (PA) levels and self-competence.</p> <p><italic>Material and methods</italic>: A total of 85 students aged 12–13 years old, enrolled in the 7<sup>th</sup> grade from one junior high in the Midwestern part of the U.S.A. participated. Classes were randomly assigned as coed or single-sex. The study took place during eight lessons of a basketball unit. Four of the lessons focused on skill and four focused on game play. Average heart rate (HR) levels were recorded through HR monitors. A modified version of the Confidence in Learning Mathematics scale was administered to the students.</p> <p><italic>Results</italic>: A 2 × 2 Factorial ANOVA was completed to examine the effect of setting and gender on average HR during gameplay lessons, average HR during skill-based lessons, confidence, usefulness, and appropriateness. Results revealed on average, girls had fewer bpm compared to boys during gameplay. Also, girls in the single-sex setting had, on average, higher HR during gameplay compared to girls in coeducational.</p> <p><italic>Conclusions</italic>: Similarly, to other research, males had higher bpm during game play than females and higher HR’s in the single-sex setting than the coed setting. This suggests that during basketball it might be more ideal for females to participate in a single-sex setting to elicit more activity.</p> </abstract>ARTICLE2021-06-04T00:00:00.000+00:00The effects of wearing high heeled shoes on the muscles and joints of lower limb<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: The aim of this study is to investigate whether the lower extremity muscles’ force/torque/strength and range of motion may be affected in females wearing high heeled shoes and not wearing high heeled shoes.</p> <p><italic>Material and methods</italic>: The study was carried out with 136 females aged between 18 and 45 years. The first group consisted of 66 females wearing 5 cm or higher high heeled shoes. The second group consisted of 70 females wearing shoes having heel height less than 5 cm. The Nicholas Manual Muscle Tester was used to evaluate lower extremity muscle force/torque/strength, while range of motion was assessed with an electronic goniometer. The SPSS 21.0 program was used for statistical analysis.</p> <p><italic>Results</italic>: A significant difference was found in the lower extremity muscles’ force (except for hip adduction, dorsiflexion, metatarsophalangeal joint and interphalangeal joint extension), and muscles’ torque (except for hip adduction, dorsiflexion and left tibialis anterior muscle) and muscles’ strength values (except for hip adduction, dorsiflexion and tibialis anterior muscle). Also, as heel height increased, the range of motion of hip joint flexion, internal rotation and plantar flexion increased significantly.</p> <p><italic>Conclusions</italic>: Excessive use of high heeled shoes can cause changes in muscle force/torque/strength and joint range of motion.</p> </abstract>ARTICLE2021-03-15T00:00:00.000+00:00Quality of life in Brazilian martial arts and combat sports practitioners<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: Martial arts and combat sports have been an alternative for individuals seeking the health benefits of physical activity and exercise, but little is known about its practitioners’ quality of life. Therefore, this study aimed to investigate the quality of life of practitioners of five of the most common modalities in Brazil.</p> <p><italic>Material and methods</italic>: A total of 922 young men, competitive and recreational practitioners of Brazilian jiu-jitsu, judo, karate, kung-fu, and taekwondo, answered the Brazilian version of the WHOQOL-BREF questionnaire.</p> <p><italic>Results</italic>: The results for each domain – physical, psychological, social, and environmental – are, respectively, as follow (mean ± standard deviation): Brazilian jiu-jitsu: 74 ± 11, 75 ± 12, 77 ± 17, 67 ± 14; judo: 74 ± 13, 75 ± 12, 77 ± 15, 64 ± 12; karate: 76 ± 13, 75 ± 12, 78 ± 15, 64 ± 13; kung-fu: 77 ± 13, 75 ± 13, 74 ± 17, 65 ± 13; taekwondo: 76 ± 12, 76 ± 11, 78 ± 16, 64 ± 13; total: 75 ± 13, 75 ± 12, 77 ± 16, 65 ± 13. There was no difference between modalities and no interaction between modalities and experience level. All groups and the total sample presented higher values than the normative national data in the physical and psychological domains. This was also the case for the judo, karate, and taekwondo groups, as well as the total sample in the social domain, and for the Brazilian jiu-jitsu and the whole sample in the environmental domain. Additionally, in the whole sample competitors scored higher than recreational practitioners in the psychological domain.</p> <p><italic>Conclusion</italic>: These findings reveal that the practice of these modalities is associated with higher quality of life than the normative values. Longitudinal studies are warranted for a better understanding of this association.</p> </abstract>ARTICLE2021-07-05T00:00:00.000+00:00Contrasts in fitness, motor competence and physical activity among children involved in single or multiple sports<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: While there is wide debate around specialization in one sport, there is a lack of information about fitness levels and motor competence of children participating in single or multiple sports.</p> <p><italic>Material and methods</italic>: The study involved 358 fifth-grade children who participated in a set of health-related fitness and motor competence tests over two consecutive years. A subsample of children (<italic>n</italic> = 109) wore an accelerometer for seven consecutive days. The independent samples t-test and ANCOVA were used to compare differences between single and multi-sport participants in study variables and changes between baseline and follow-up.</p> <p><italic>Results</italic>: Multi-sport participants performed better in shuttle run (baseline/follow-up; <italic>p</italic> = 0.001/<italic>p</italic> = 0.006), push-up (<italic>p</italic> = 0.006/<italic>p</italic> = 0.036), and five leap tests (<italic>p</italic> = 0.001/<italic>p</italic> = 0.009) in baseline than single sport participants among boys. Likewise, multi-sport participants showed significantly more improvement in the throwing and catching combination test between study years among boys F<sub>1,159</sub> = 3.570, <italic>p</italic> = 0.030. Among girls, no differences were found in any study variable between single and multi-sport participants.</p> <p><italic>Conclusions</italic>: From the perspective of fitness and motor competence tests, there are no arguments for participating in just one sport at an early age. Instead, multi-sport participants performed better than single sport participants in the majority of test variables.</p> </abstract>ARTICLE2021-01-27T00:00:00.000+00:00Effects of self-controlled knowledge of performance on motor learning and self-efficacy: A kinematic study<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: To evaluate the effects of providing the learners with self-controlled knowledge of performance (KP) on motor learning and self-efficacy (SE) in a dart-throwing motor task.</p> <p><italic>Material and methods</italic>: The participants were thirty female university students who were divided into two groups including self-control and yoked groups. Participants performed five blocks of five trials in the acquisition phase, and retention and transfer tests of 10 trials one day later. Intra-limb coordination patterns (movement pattern), throwing scores, and SE (both movement pattern and movement outcome) were measured as dependent variables. Independent t test and one-way ANOVA with repeated measures were used as statistical tests.</p> <p><italic>Results</italic>: The self-controlled group performed significantly better than yoked group on movement pattern during the acquisition phase (F<sub>1,28</sub> = 24.239, p = 0.001) and the retention test (t<sub>28</sub> = –3.074, p = 0.007). However, there were no significant differences between groups in terms of throwing scores and SE during the acquisition, retention, and transfer phases (all p &gt; 0.05).</p> <p><italic>Conclusion</italic>: Providing self-controlled KP can improve learning of movement pattern in the novices but do not necessary increase movement outcome or SE.</p> </abstract>ARTICLE2021-06-14T00:00:00.000+00:00Longevity of Polish male Olympic medallists born between 1888 and 1965<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: The aim of the study was to analyse the lifespan of Polish male Olympic medallists in comparison to the general male population.</p> <p><italic>Material and methods</italic>: The study included 238 Polish male Olympic medallists who participated in the Olympic games in 1924–1992. Duration of life in relation to the general Polish population was assessed. The age of acquiring their first medal, type and number of medals won and sports discipline were taken into consideration.</p> <p><italic>Results</italic>: Polish male Olympic medallists born before 1940 lived over 8 years longer in comparison to the general population (p &lt; 0.0001, d = 0.689 and d = 0.750). Over 80% of them lived up to 65 years of age and over 40% up to 80. In the general population only &lt;70% and &lt;30%, respectively, reached the equivalent lifespan (p = 0.010 and p = 0.040, RR = 0.480 and RR = 0.783). Kaplan-Meier analysis demonstrated that survival was shorter in Olympic medallists who won their first medal before the age of 25 (p = 0.040) and in those engaging in endurance or power sports vs. mixed or skill disciplines (p = 0.010).</p> <p><italic>Conclusions</italic>: Polish male Olympic medallists lived significantly longer than the general population of Polish men. The longevity of male Olympic medallists was affected by the age of acquiring their first medal and by the category of sport practised.</p> </abstract>ARTICLE2021-01-27T00:00:00.000+00:00Physical fitness changes among amateur soccer players: effects of the pre-season period<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: To assess changes in physical fitness of amateur soccer players after a pre-season training period and baseline fitness dependencies.</p> <p><italic>Material and methods</italic>: Twenty-one amateur soccer players were assessed during the pre-season. The following physical variables were assessed before and after a two-month pre-season training period: (i) cardiorespiratory fitness, (ii) strength and power, and (iii) change of direction (COD).</p> <p><italic>Results</italic>: Significant decreases were found for countermovement jump (CMJ) (p &lt; 0.001; d = 1.161), drop jump (DJ) (p = 0.014; d = 0.958), and horizontal jump (HJ) (p = 0.042; d = 0.640), while no significant changes were found for the overall variables from the beginning to the end of pre-season. Fit players revealed significant decreases for CMJ (p = 0.002; d = –2.495), DJ (p = 0.004; d = –1.760), HJ (p = 0.028; d = –1.005), COD deficit (p = 0.034; d = 1.013), and maximal aerobic speed (MAS) (p = 0.026; d = –4.053). No significant changes were found for unfit players.</p> <p><italic>Conclusions</italic>: Amateur soccer coaches should consider assessing physical qualities at the beginning of pre-season and use the free-of-charge monitoring tools such as session-rate of perceived exertion (s-RPE) during the training process.</p> </abstract>ARTICLE2021-01-29T00:00:00.000+00:00The impact of fencing training symmetrisation on simple reaction time<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: The symmetrisation of movements can be a way to develop individual coordinative skills, and to prevent the occur-rence of injuries. For this reason, in this study an attempt was made to evaluate and compare simple reaction time and movement time for épée fencers of different sports classes, and to determine the impact that three years of symmetrisation training and unilateral training have on the speed of reaction components and on dynamical asymmetry.</p> <p><italic>Material and methods</italic>: The study was conducted on 60 women épée fencers of different sports classes, and it was repeated in two groups after three years of unilateral and symmetrisation training. Simple reaction time and movement time for the dominant and the non-dominant hand were analysed using Vienna Test System.</p> <p><italic>Results</italic>: Women épée fencers of high sports class were characterised by a significantly faster reaction time than their less experienced colleagues. In tests conducted after three years of symmetrisation training, athletes from the experimental group achieved also much better results in reaction time (RT) than those from the control group training with the unilateral method.</p> <p><italic>Conclusions</italic>: Long-time unilateral training of master class women épée fencers led to dynamical asymmetry, which in the future could cause injuries and have a negative impact on the development of selected motor skills. Symmetrical training conducted in the experimental group had a positive impact on reaction time indicators as well as on movement time indicators, and it prevented the occurrence of dynamical asymmetry in the tested competitors. Thus, it can be inferred that symmetrical exercises will have a positive impact on training effectiveness and on versatility of athletes.</p> </abstract>ARTICLE2021-08-09T00:00:00.000+00:00The effect of fatigue on jump height and the risk of knee injury after a volleyball training game: A pilot study<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: To investigate the effect of fatigue, induced by a volleyball training game on the risk of Anterior Cruciate Ligament (ACL) injury.</p> <p><italic>Material and methods</italic>: Thirteen female volleyball college athletes, ages 18 to 21 years old, completed jump landings from a box 30 cm height, prior and post a 60-minute volleyball training game. The clinical tool Landing Error Scoring System (LESS) was employed in order to evaluate the technique of landing prior and post the game. The level of fatigue induced by the volleyball game was assessed by vertical jump test and Borg Rating of Perceived Exertion (RPE) Scale pre and post-game. In order to compare measurements pre and post-game t-tests for dependent samples were used.</p> <p><italic>Results</italic>: Participants performed lower vertical jumps post-game with a Confidence Interval of 26.2 ± 2.3 cm (pre-game) and 24.9 ± 2.2 cm (post game). The difference between pre and post-game was found to be statistically significant with a t<sub>12</sub> = 2.55 and a p-value of 0.026. In the case of assessing fatigue, the Borg RPE scale scores were found to be statistically significant (t<sub>12</sub> = 14.05, p &lt; 0.001) higher post-game (10.2 ± 0.6), as compared to pre-game (6.5 ± 0.4). Similarly, LESS scores increased significantly (t<sub>12</sub> = 2.21, p = 0.047), post-game (6.3 ± 1.1) compared to pre-game (5.8 ± 1.0) that prove poorer landing ability.</p> <p><italic>Conclusion</italic>: It seems that a short duration volleyball training game induces fatigue and negatively affects the jumping and landing ability.</p> </abstract>ARTICLE2021-06-18T00:00:00.000+00:00Effort distribution analysis for the 800 m race: IAAF World Athletics Championships, London 2017 and Birmingham 2018<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: To analyse the distribution of effort in the 800 m event at the IAAF World Athletics Championships in London 2017 (outdoor, 44 men, 45 women) and in Birmingham 2018 (indoor, 9 men, 14 women).</p> <p><italic>Material and methods</italic>: A total of 187 individual performances during heats, semi-finals, and finals were analysed. The official split times of each athlete every 100 m were taken as reference for the analysis of: times; percentages of times in regard to the final time; speed; changes in position during the races; percentage deviations in terms of the average time per race per section of 100, 200 and 400 m.</p> <p><italic>Results</italic>: There are different strategies used in the elite 800m race that are related to sex differences, the management of energy consumption and the differences and similarities between indoor and outdoor races.</p> <p><italic>Conclusions</italic>: Although diverse pacing strategies exist, more balanced strategies, after a fast start, have better results.</p> </abstract>ARTICLE2021-03-23T00:00:00.000+00:00Investigating the landing kinetics factors and preparatory knee muscle activation in female handball players with and without dynamic knee valgus while performing single leg landing<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: to examine the differences in landing kinetics factors (LKF) to assess the whole body stability and preparatory muscle activation (PMA) in female handball players with and without dynamic knee valgus.</p> <p><italic>Material and methods</italic>: Twenty-four professional female handball players (11 with (DKV) and 13 without (Control) dynamic knee valgus) were asked to perform three trials of a single-leg landing. LKF and surface EMG were recorded. Initial contact knee valgus angle (IC KVA), vertical ground reaction force (vGRF), confidence ellipse area of center of pressure (CEA), time to stability (TTS) and EMG from 100 ms prior to ground contact were used in the data analyses.</p> <p><italic>Results</italic>: Multivariate analyzing of LKF showed significant differences between two groups (p = 0.001) while for PMA the result was not significant (p = 0.361).</p> <p><italic>Conclusion</italic>: Altered landing mechanism considered as a predictor of non-contact knee injuries such as ACL rupture. Therefore according to current study it seems important to focus on reducing valgus angle in designing injury prevention program.</p> </abstract>ARTICLE2021-05-24T00:00:00.000+00:00Effect of additional load on angular parameters during gait and balance in children with hemiparesis – Cross sectional study<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim</italic>: To study the effect of additional load over ankle and knee joints on angular parameters during gait and balance in children with hemiparesis.</p> <p><italic>Material and methods</italic>: 10 children with hemiparesis were recruited and stratified into 2 chronological age groups: group A (4–8 years) and group B (9–12 years). Additional loads of 0.7 kg and 1.1 kg were placed on the affected and non-affected lower limb at the ankle and knee joint for group A and group B respectively. Angular parameters during gait were assessed using Kinovea software (version 0.8.15) and balance using the Pediatric Balance Scale.</p> <p><italic>Results</italic>: Application of additional load of 0.7 kg over the non-affected leg knee joint is able to produce significant changes in ankle joint angles (p &lt; 0.05) at initial contact and knee joint angles at heel-off (p &lt; 0.05), toe-off (p &lt; 0.001), acceleration (p &lt; 0.05) and deceleration (p &lt; 0.05) phases of gait and balance in group A, whereas on application of additional load of 1.1 kg over the affected leg at the ankle joint significant improvement in knee joint angles at initial contact (p &lt; 0.001) and the deceleration (p &lt; 0.05) phase of gait in group B was observed. There was significant improvement in the Pediatric Balance Scale score in both groups (p &lt; 0.05).</p> <p><italic>Conclusions</italic>: Additional load over knee and ankle joints of the affected and non-affected leg showed more improvement in angular parameters during gait and balance in younger children with hemiparesis than older children, as they present an immature form of gait that can be modified, corrected and brought back to a normal angle.</p> </abstract>ARTICLE2021-04-27T00:00:00.000+00:00Feature extraction and gait classification in hip replacement patients on the basis of kinematic waveform data<abstract> <title style='display:none'>Abstract</title> <p><italic>Study aim:</italic> To find out, without relying on gait-specific assumptions or prior knowledge, which parameters are most important for the description of asymmetrical gait in patients after total hip arthroplasty (THA).</p> <p><italic>Material and methods:</italic> The gait of 22 patients after THA was recorded using an optical motion capture system. The waveform data of the marker positions, velocities, and accelerations, as well as joint and segment angles, were used as initial features. The random forest (RF) and minimum-redundancy maximum-relevance (mRMR) algorithms were chosen for feature selection. The results were compared with those obtained from the use of different dimensionality reduction methods.</p> <p><italic>Results:</italic> Hip movement in the sagittal plane, knee kinematics in the frontal and sagittal planes, marker position data of the anterior and posterior superior iliac spine, and acceleration data for markers placed at the proximal end of the fibula are highly important for classification (accuracy: 91.09%). With feature selection, better results were obtained compared to dimensionality reduction.</p> <p><italic>Conclusion:</italic> The proposed approaches can be used to identify and individually address abnormal gait patterns during the rehabilitation process via waveform data. The results indicate that position and acceleration data also provide significant information for this task.</p> </abstract>ARTICLE2021-06-04T00:00:00.000+00:00en-us-1