Acute effects of differing duration of static stretching on speed performance Farklı sürelerde uygulanan statik germenin sürat performansına akut etkisi

Abstract Purpose: The purpose of this study was to determine the acute effects of differing duration (15s, 30s, 45s) of static stretching on speed performance. Method: Twenty students in Physical Education and Sports (age 23.3 ± 2.0 years, height 175.7 ± 5.8 cm, weight 67.6 ± 8.6 kg) implemented 4 differing duration static stretching protocol on ​​noncontiguous days. After low intensity aerobic exercise subjects applied 15s static stretching (SG15), 30s static stretching (SG30), 45s static stretching (SG45) and low intensity aerobic exercise without any stretching application (KU). Subjects performed 20m sprint test after each stretching protocol. Differing duration of static stretching methods were compared by repeated measures ANOVA and post-hoc methods. Results: Differences between KU and SG15 (%5.1), KU and SG30 (%6.6) and KU and SG45 (%10.9) was significant (p<0.001). In addition significant difference was observed between SG15 and SG45 (p<0.032). Conclusion: The results of this study showed that static stretching application of lower extremities have negative impact on the 20m sprint performance. Longer sprint performances were observed as the duration of static stretching increases. These results indicate that static stretching applications were inadequate to prepare the athletes for the activities (such as sprinting) which require high power production. Özet Amaç: Bu çalışmada farklı sürelerde (15, 30 ve 45 sn) uygulanan statik germenin sürat performansına olan akut etkisinin incelenmesi amaçlanmıştır. Yöntem: Yirmi Beden Eğitimi ve Spor öğrencisi erkek sporcu (yaş 23,3 ± 2.0 yıl, boy 175,7 ± 5.8 cm, beden ağırlığı 67.6 ± 8.6 kg) birbirini izlemeyen günlerde 4 farklı protokolü uygulamışlardır. Bu araştırma düşük yoğunluklu aerobik egzersizi takiben, 15 sn süreli statik germe (SG15), 30 sn süreli statik germe (SG30), 45 sn süreli statik germe (SG45) ve sadece düşük yoğunluklu aerobik egzersiz (KU) (kontrol-hiç germe olmadan) yöntemlerinden oluşmaktaydı. Sporcular her protokolden sonra 20 m sürat testini gerçekleştirmişlerdir. Isınma yöntemleri tekrarlı ölçümlerde ANOVA ve post-hoc yöntemleri ile karşılaştırılmıştır. Bulgular: Sürat performansları açısından KU protokolü ile SG15 protokolü arasında % 5.1’ lik fark (p<0.001), KU protokolü ile SG30 protokolü arasında % 6.6’ lık fark (p<0.001) ve KU protokolü ile SG45 protokolü arasında % 10.9’ luk fark (p<0.001) anlamlı bulunmuştur. Ayrıca SG15 protokolü ile SG45 protokolü arasında anlamlı fark (p<0.032) bulunmuştur. Sonuç: Bu araştırmanın sonuçları, alt ekstremiteye yönelik uygulanan statik germe uygulamalarının sporcuların sürat performanslarını düşürdüğünü göstermektedir. Statik germenin süresi arttıkça sürat performansının düştüğü gözlenmiştir. Bu sonuçlar statik germe uygulamalarının, sporcuları yüksek güç üretimi gerektiren aktivitelere (sürat gibi) hazırlamak için yetersiz kaldıklarını göstermektedir. 

Normative values for physical fitness in children aged 11-17 in Kosovo

Background and Study Aim: In the present study, the purpose was to determine the normative values for physical and biomotoric characteristics of children aged 11-17 in Kosovo. Material and Methods: 742 students who were selected according to the Random Sampling Method from 24 schools determined in the cities and rural areas in all regions were included in the study (n = 347 girls, n = 395 - boys). Volunteering students who did not have any acute or chronic disease that might avoid testing were included in the study after the permissions were received from the Ministry of National Education, Principals of the Schools, and the support of the parents. The declarations of Helsinki were taken into consideration in the study. Results: The results of each test were given as the norm values according to gender and age together with 20% groups, which is considered as the Canadian Standard. The data on the physical and biomotoric characteristics of the children living in Kosovo were compared with the data of the World Health Organization and the literature data of other countries. Conclusions: While the children living in Kosovo showed higher performances in the tests that were affected by anthropometric properties like height and body fat percentage and by genetic properties like the speed of the movements of the arms when compared with the children from other countries from the same age group; they had lower performances in the tests that were affected by life style and physical activity levels like endurance, long jump, and flexibility

Biomechanical effects of daily physical activities on the lower limb

Objective: The aim of this study was to determine the joint torques on the lower extremity during the daily physical activity movements of sit-to-stand, crouch down-stand up, and stair climbing without using an external device.Methods: The study subject was a healthy 26-year-old male without any physical problems. A linksegment model was prepared according to the subject's individual anthropometric characteristics and transferred to the MATLAB® program. Joint torques were calculated using SimMechanics(TM) software. Motions were recorded by one digital video camera as the subject performed the movements (sit-tostand from 20 cm and 40 cm height, crouch down-stand up, and climbing 10 cm and 20 cm high step) and the joint's position data was obtained using a digitization process. In addition, the vertical ground reaction forces were measured using a force plate in order to test the accuracy of the link-segment model. Lower extremity joint torques were calculated.Results: Maximum joint torques occurred in the knee joint. The knee and the ankle joints were the most loaded joint during the high step movement. The highest torques of the knee and ankle joint were 157.2 Nm and 146 Nm, respectively, during the movements. Knee joint torque and the ankle joint torque increased when the sitting height increased. The hip joint experienced the least amount of load during the movements.Conclusion: The knee joint has enough strength against high torques during extension and flexion movement. Joint torques can be successfully calculated using a simulation process involving an inverse dynamics method without an external device mounted on the limbs. The obtained data can be used in the design of prosthetics and orthotics and for structural analysis of the bone

Електромиографические відповіді на вправи на скандинавські згинання рук і згинання ніг лежачи у футболістів

Background and Study Aim. The aim of this study is to examine the electromyographic responses to Nordic curl and prone leg curl exercises, having two different mechanics. Material and Methods. The athletes performed the prone leg curl and Nordic curl exercises in random order, 6 repetitions each. Electromyographic data of semimemranosus, semitendinosus, biceps femoris and rectus femoris muscles were recorded by 8-channel electromyography in order to examine the muscle responses to exercises. Total duration of exercise, cumulative integrated electromyographic values and muscle activation rates in 5 different intensity zones determined according to MVC% values have been compared. Results. Prone leg curl exercise occurred in less time than Nordic curl exercise. According to the cumulative integrated electromyography data results, all muscles showed similar muscle activation in both exercises. Comparing the muscle activation rates in the five intensity zones, more muscle activity was observed for Nordic curl exercise in the first intensity zone, while prone leg curl exercise was more active in the third and fourth zones. During the prone leg curl exercise, the muscle activation rate of the dominant leg is higher in the first intensity zone, whereas the non-dominant leg in the fourth intensity zone has a higher muscle activation. During the Nordic curl exercise, the muscle activation rates of the dominant leg in the first and fifth intensity zones are higher, whereas the nondominant leg in the fourth intensity zone is higher. Conclusions. Prone leg curl exercises can be preferred in order to stimulate high muscle activation in a short time. Comparing the two exercises there was no significant difference in muscle activity in dominant and nondominant legs.Передумови та мета дослідження. Метою даного дослідження є вивчення електроміографічні реакції на вправи на скандинавські згинання рук і згинання ніг лежачи на животі з двома різними механізмами.Матеріал і методи. Спортсмени виконували вправи на згинання ніг лежачи і скандинавські згинання в довільному порядку по 6 повторень кожне. Електроміографічні дані напівперетинчасті, напівсухожильний м'язів, двоголового м'яза стегна і прямого м'яза стегна реєстрували за допомогою 8-канальної електроміографії для вивчення реакції м'язів на вправи. Порівнювали загальну тривалість вправи, сукупні інтегровані електроміографічні показники і швидкість м'язової активації в 5 різних зонах інтенсивності, визначених відповідно до значень MVC%.Результати. Згинання ніг лежачи на животі було виконано швидше, ніж скандинавське згинання. Згідно кумулятивним результатами інтегрованих даних електроміографії, всі м'язи показали однакову активацію м'язів в обох вправах. Порівнюючи рівні активації м'язів в п'яти зонах інтенсивності, велика активність м'язів спостерігалася у вправі скандинавські згинання в першій зоні інтенсивності, в той час як вправи на згинання ніг лежачи на животі були більш активними в третій і четвертій зонах. Під час вправи згинання ніг лежачи на животі швидкість активації м'язів домінуючою ноги вище в першій зоні інтенсивності, тоді як у недоминантной ноги в четвертій зоні інтенсивності активація м'язів вище. Під час виконання скандинавських згинань швидкість м'язової активації домінуючою ноги в першій і п'ятій зонах інтенсивності вище, тоді як у домінує ноги в четвертій зоні інтенсивності вище.Висновки. Вправи на згинання ніг лежачи на животі можуть бути кращими, щоб стимулювати високу м'язову активацію за короткий час. При порівнянні цих двох вправ не було виявлено значної різниці в м'язової активності домінуючих і не домінуючих ніг

ACUTE EFFECTS OF A RESISTED DYNAMIC WARM-UP PROTOCOL OH JUMPING PERFORMAHCE

This study aimed to investigate the kinematic and kinetic changes when resistance is applied in horizontal and vertical directions, produced by using different percentages of body weight, caused by jumping movements during a dynamic warm-up. The group of subjects consisted of 35 voluntary male athletes (19 basketball and 16 volleyball players; age: 23.4 +/- 1.4 years, training experience: 9.6 +/- 2.7 years; height: 177.2 +/- 5.7 cm, body weight: 69.9 +/- 6.9 kg) studying Physical Education, who had a jump training background and who were training for 2 hours, on 4 days in a week. A dynamic warm-up protocol containing seven specific resistance movements with specific resistance corresponding to different percentages of body weight (2%, 4%, 6%, 8%, 10%) was applied randomly on non consecutive days. Effects of different warm-up protocols were assessed by pre-/post- exercise changes in jump height in the countermovement jump (CMJ) and the squat jump (Si) measured using a force platform and changes in hip and knee joint angles at the end of the eccentric phase measured using a video camera. A significant increase in jump height was observed in the dynamic resistance warm-up conducted with different percentages of body weight (p0.05). In jump movements before and after the warm-up, while no significant difference between the vertical ground reaction forces applied by athletes was observed (p>0.05), in some cases of resistance, a significant reduction was observed in hip and knee joint angles (p<0.05). The dynamic resistance warm-up method was found to cause changes in the kinematics of jumping movements, as well as an increase in jump height values. As a result, dynamic warm-up exercises could be applicable in cases of resistance corresponding to 6-10% of body weight applied in horizontal and vertical directions in order to increase the jump performance acutely

Development of A Wearable Exercise Device for Rehabilitation of Hemiplegic Hand

Millions of people suffer a stroke each year. One of the problems after stroke is hemiplegic hand. In previous studies a lot of robotic based devices has been suggested for rehabilitation of hemiplegic hand. Actuators using for force transmitting in previous devices have some disadvantages. One of them is misalignment on the centre of rotation between joints used in devices and joints of the hand. In this study a novel device is suggested to perform the finger exercises. The device has a cable and spring driven mechanism with an electrical linear actuator. The device allows both passive and active exercises. It is aimed that the device is suitable for at-home use, wearable, portable and low cost. It is expected from the new device that it will reduces the rehabilitation cost and therapy period. The device can be used for other rehabilitation treatments such as nerve injury, nerve compression, tendon injury, fracture and sport injury besides stroke rehabilitation