Physical Education and Sport

The aim of the study was to define activation characteristics of knee muscles of the kicking leg during the in-step kick and interpret these in relation to isokinetic strength parameters and ball velocity in professional (N = 14) compared to amateur (N = 17) soccer players. Electromyographic (EMG) recordings were taken from the rectus femoris (RF), vastus lateralis (VL), vastus medialis (VM), long head of biceps femoris (BF) and medial gastrocnemius (GAS) as players performed three successful maximal in-step kicks using a 0 • approach angle with two steps to a stationary ball towards a target. Kicks were also recorded with high speed video and ball velocity was measured by a radar gun. Afterward the bilateral concentric isokinetic strength of the knee extensors and flexors was recorded. Results suggest that during the swing phase, BF activation occurred significantly earlier, RF showed reduced activation and an earlier and greater muscle activity occurred in VL and VM in professionals compared to amateur players. During knee extension, VL and VM showed a markedly greater magnitude of muscle activity in professionals; during the follow through, GAS showed reduced activity in professionals. Relationships between muscle strength and performance (ball speed) were found for amateurs but not for professionals (r = 0.57 to r = 0.72, p < 0.05). The findings of this study indicate that the superior performance of professional players compared to amateurs appears not to be due to muscle strength factors but rather to subtle differences in technique, as indicated by EMG data, throughout both the build up and execution of the kick.

Yüzeyel elektromiyografi (sEMG), uzun yıllar boyunca laboratuar araştırmalarında kullanılan bir araç olarak karşımıza çıkmasına rağmen, elektrik, elektronik, bilgisayar ve biyomedikal alanlarda teknolojinin de gelişmesiyle birlikte kinesiyoloji, rehabilitasyon, spor tıbbı, spor bilimleri ve birçok spor branşında farklı amaçlarla kullanılmaya başlanmıştır. EMG uygulamaları sonucunda elde edilen veriler; merkezi kontrol stratejileri, sinir hücreleri boyunca olan sinyalin sinir kas kavşağına transferi, motor ünitede kas hücrelerinin elektriksel aktivasyonu, karmaşık biyomekaniksel olaylar zinciri, agonist ve antagonist kas tendonları üzerine etki eden ve kemiklere taşınan baskının üretimi hakkında bilgi edinilmesini sağlar. Spor bilimlerinde kassal aktivasyonun değerlendirildiği elektromiyografi uygulamaları ise, teknik gelişimin değerlendirilmesi, uygun antrenman programlarının oluşturulması, sporcunun gelişiminin takip edilmesi, yetenek seçimi amaçlarıyla kullanılabilmektedir Yüzeyel EMG spor bilimlerinde tek başına ölçüm aracı olarak kullanıldığı gibi, görüntü analizi, kuvvet platformu, izokinetik dinamometre vb. cihazlardan alınan bilgileri destekleyici unsur olarak da kullanılmaktadır. Bu bilgiler doğrultusunda antrenör ve spor bilimciler farklı antrenman yaklaşımlarını ortaya koyabilirler.

This study investigated the efficacy of high and low-frequency acute whole-body vibration (WBV) on postural control ability. WBV stimulus were applied the following determinants: (1) type (vertical) (2) frequency (30 and 40 Hz), (3) stance position (static squat position), (4) amplitude (4mm mm), (5) knee flexion angle (120°) and time (60s).Motion of the point of application of the vertical component [medio-lateral (ML) and anterio-posterior (AP)] of the ground reaction force (center of pressure, COP). The study results showed that static WBV stimuli given at low and high frequencies and 4 mm amplitude resulted in a different postural adaptation (p&lt;0.05). The somatosensory stimulation more rapidly adapted to the vibration at 40 Hz-4 mm.

Denge, atıcılık gibi statik spor branşlarında ve futbol, jimnastik, güreş gibi maksimum çeviklik gerektiren dinamik sporlarda, spor performansı açısından oldukça büyük öneme sahiptir. Denge, istemli hareket öncesinde, sırasında ve sonrasında postural ayarlamalar ile stabilite durumunu tekrar kazanmak için, stabilizasyonu bozan durumlara ve eksternal pertürbasyonlara karşı hızlı ve etkili bir şekilde reaksiyon gösterebilme yeteneği olarak tanımlanmaktadır. Ayrıca denge, içsel ve dışsal güçlerin ve çevreyi içeren faktörlerin dinamik integresyonu tarafından sürdürülmektedir. Dışsal (kaygan zemin üzerinde yürümek, ışık değişimi vb.) ve içsel denge perturbasyonlarına [kas sertliği (stiffness), kas iskelet yaralanmaları ve yorgunluk gibi] karşı dik duruş pozisyonunun devam ettirilebilmesi; sensör (somatosensör, görsel ve vestibular) ve motor sistemin entegresyonunu gerektirmektedir. İçsel perturbasyonlara maruz kalınan durumlarda postural salınımın belirlenmesine yönelik gerçekleştirilmiş çalışmalar bulunmaktadır. Bu çalışmalar incelendiğinde en genel içsel perturbasyon postural kontrol paradigmaları; (a) başın hareketini, (b) gözlerin kapalı olduğu durumları, (c) içsel odaklanma durumunu ve (d) kassal yorgunluğu içermektedir. Egzersiz sonrasında dengeyi bozan ya da kötüleştiren temel faktör olarak ifade edilen yorgunluk; eklemlerin proprioseptif ve kinestetik özelliklerini zayıflatarak kas iğciğinin deşarj olma eşiğini arttırmaktadır. Bu durum afferent geribildirimi olumsuz etkileyerek eklem farkındalığında istenmeyen değişimlere neden olmaktadır. Bu bağlamda, kassal yorgunluk; periferal proprioseptif sistemi, merkezi propriosepsiyon sürecini ve aynı zamanda kuvvet üretim kapasitesini değiştirdiği bilinen fiziksel, profesyonel ya da rekreasyonel aktivitelerin kaçınılmaz bir fenomenini sunmaktadır. Bu çalışmada, farklı egzersiz formlarının postural kontrol üzerinde ne gibi etkilerinin olduğunu ortaya koyan araştırmalara yer verilecektir.

Günlük hayatta, herhangi biri ile konuşurken, sırada beklerken ya da iş yaşamımızda genellikle birkaç dakikadan daha uzun süre ayakta durmak zorunda kalırız. Bu gibi doğal duruşlar sırasında, vücut sürekli düşük genlikli, yavaş salınımlı ve tüm vücut hareketleri ile karakterize edilen postural değişimler göstermektedir. Bu değişimler özellikle sportif etkinliklerde önemlidir. Çünkü sportif etkinliklerde bir motor aktivitenin gerçekleştirilebilmesi, hem dışsal dengeyi (kaygan zemin üzerinde yürümek, ışık değişimi vb) hem de içsel dengeyi bozucu güçlere (kas stiffness'ı, kas iskelet yaralanmaları ve yorgunluk vb) karşı denge görevini sürdürmeyi gerektirmektedir. Bu görevin en az efor ile gerçekleştirilebilmesi için, devam eden duruş sırasında postural değişimler ve vücut salınımındaki artışa en etkili yanıtın verilmesi gerekmektedir. Bu yanıt ise sensör (somatosensör, görsel ve vestibular) ve motor sistemin oldukça kompleks bağlantısını gerektiren postural kontrol sisteminin devreye girmesi ile gerçekleşmektedir. Postural kontrol, dinamik sensör-motor sürecin etkileşimine dayanan kompleks motor bir beceridir ve denge fonksiyonu verilen görev doğrultusunda postural kontrol altındaki tüm sistemlerin etkili kullanımını gerektirmektedir. Bu nedenle postural stabilitenin sportif performans açısından rolünün belirlenmesine yönelik birçok araştırmanın yürütüldüğü görülmektedir. Bu araştırmalar sonucu dinamik ve statik koşullar altında postural stabilitenin değerlendirilebilmesi için çeşitli metotlar ortaya çıkarılmıştır. Bu metotlar kullanılarak her bir spor branşının gereklilikleri ile ilişkili farklı postural sensör-motor stratejiler geliştirilmiştir. Bu çalışma; farklı spor branşlarına özgü motor görevlerin gerçekleştirilmesi sırasında ortaya çıkan postural salınıma ilişkin araştırmaları incelemeyi amaçlamaktadır. Bu amaç doğrultusunda spor branşındaki uzmanlığın postural salınım üzerinde nasıl bir etkiye sahip olduğuna dair spor branşları ile ilgili araştırmalara yer verilecektir. Araştırma destekli bilgi sentezini içeren bu çalışmanın sportif performansın ön koşullarından biri olan postural kontrol sisteminin anlaşılmasına katkı sağlayacağı düşünülmektedir.

The purpose of the study was to investigate the effects of functional balance training on static and dynamic balance performance, kicking velocity and to define the relationship between balance ability and kicking velocity of adolescent soccer players. Material and Methods: Sixteen male players randomly divided into 2 groups (Control Group: age 14,23±0,44; Training Group: age 14,31±0,48). While the control group (n=8) followed regular soccer training, the training group (n=8) performed a functional balance training program additively. The balance training was performed on both stable ground and unstable surface (BOSU ball). SportKat2000 system were used to elicit static and dynamic balance scores of right, left and both leg stance of the soccer players. Results: All static balance variables (dominant, non-dominant and both leg) of training group and one variable (non-dominant leg) of control group showed statistically significant differences (p<0,05) after training. Dynamic dominant leg scores of training group and dynamic non-dominant leg scores of control group were statistically significant as well. Ball velocity of training group improved %5.6 in training group and %3.7 in control group. Besides, dominant leg ball velocity correlated with dynamic dominant (p<0.05; r:-0,767) and both leg (p<0.05; r:-0,787) balance ability for training group. Non-dominant ball velocity also correlated with dynamic dominant (p<0.01; r:-0,844) and dynamic non-dominant leg (p<0.05; r:-0,778) balance ability in training group after training period. Conclusion: As a conclusion, functional balance training performed three times in a week positively affect the balance ability and kicking performance of adolescent soccer players.

The aim of this study was to determine the relationship among maximum isokinetic concentric knee torque, muscle activity (EMG) and vertical jumping height of Turkish elite male volleyball players. M Ma at te er ri ia al l a an nd d M Me et th ho od ds s: : Twelve elite male volleyball players were included voluntary in this study. EMG activity was recorded on the vastus lateralis (VL), vastus medialis (VM), rectus femoris (RF) and biceps femoris (BF) muscles of volleyball players during five maximal isokinetic concentric-concentric contractions at 60°/s, 180°/s and 240°/s. Peak anaerobic power output was calculated using vertical jumping heights. A repeated measures analysis of variance (ANOVA) was used to compare torque values in different angular velocities. Pearson's correlation coefficient was used to evaluate the relationship between torque and muscle activation values. The statistical significance level was set at p<0.05. R Re es su ul lt ts s: : The results of this study show that Hamstring/Quadriceps (H:Q) ratios are greatest at an angular velocity of 240°/s. Differences in EMG activity during isokinetic testing were observed between the knee extensor (VL, VM) and flexor muscles (BF) (p<0.05). Repeated maximal isokinetic concentric contractions caused to increase the EMG activity of the knee and flexor muscles (p<0.05). In this study, it is demonstrated that volleyball players produced significantly higher counter movement jumping (CMJ) heights than squat jumping (SJ) heights (10%) (p=0.028). The maximum power of a CMJ was higher than that of an SJ (p=0.000), concentric work (p=0.001) and peak anaerobic power (p=0.020). Additionally, negative correlation was observed between VM, RF and BF muscle activation and isokinetic concentric-concentric torque values. C Co on nc cl lu us si io on n: : It was thus concluded that the muscle activity of the knee extensor and flexor muscles changes with change in isokinetic torque at different angular velocity and repetition. K Ke ey y W Wo or rd ds s: : Muscle activation; torque; isokinetic force Ö ÖZ ZE ET T A Am ma aç ç: : Çalışmanın amacı Türk elit erkek voleybolcuların diz ekstansör ve fleksör kaslarının maksimum konsantrik tork, dikey sıçrama ve kassal aktivasyon (EMG) değerleri arasındaki ilişkileri belirlemektir. G Ge er re eç ç v ve e Y Yö ön nt te em ml le er r: : On iki elit erkek voleybolcu gönüllü olarak çalışmaya dahil edilmiştir. Voleybolcuların vastus lateralis (VL), vastus medialis (VM), rectus femoris (RF) ve biceps femoris (BF) kaslarının kassal aktiviteleri (EMG), 60°/s, 180°/s and 240°/s açısal hızlarda, 5 maksimal izokinetik konsantrik-konsantrik kasılma sırasında kayıt edilmiştir. Zirve anaerobik güç çıktısı, squat sıçrama (SS) ve aktif sıçrama (AS) verileri hesaplanarak oluşturulmuştur. Farklı açısal hızlarda elde edilen tork değerleri tekrarlayan ölçümlerde varyans analizi (ANOVA) ile karşılaştırılmıştır. Tork ve kassal aktivasyon değerleri arasındaki korelasyonlar Pearson korelasyon katsayısı göz önünde bulundurularak analiz edilmiştir. Bütün istatistiksel testlerin anlamlılık düzeyi p<0,05 olarak alınmıştır. B Bu ul lg gu ul la ar r: : Çalışmanın bulguları 240°/sn açısal hızda en büyük Hamstring/Quadriceps (H:Q) oranına ulaşıldığını göstermektedir. İzokinetik test sırasında diz ekstansör (VL, VM) ve fleksör kasların (BF) EMG aktivitelerinde farklılıklar gözlenmiştir (p<0,05). Tekrarlı maksimal konsantrik izokinetik kasılmalar, diz ekstensör ve fleksör kaslarının EMG aktivitesinde artışa neden olmuştur (p<0,05). Voleybolcuların sıçrama yükseklikleri karşılaştırıldığında voleybolcular önemli derecede daha yüksek AS (%10) ortaya koymuşlardır (p=0,028). Maksimum AS güç çıktısı (p=0,000), konsantrik iş (p=0,001) ve zirve anaerobik güç (p=0,020) değerleri SS'dan daha yüksektir (p<0,05). Bu bulgulara ek olarak, VM, RF ve BF kassal aktivasyon değerleri ile izokinetik konsantrik-konsantrik tork değerleri arasında negatif korelasyon gözlenmiştir. S So on nu uç ç: : Sonuç olarak farklı açısal hız ve tekrarlarda diz ekstensör ve fleksör kaslarındaki EMG aktivitesi değişirken, izokinetik tork yanıtlarında da değişim gözlenmiştir.

Nerium oleander is an ornamental species of high aesthetic value, grown in arid and semiarid regions because of its drought tolerance, which is also considered as relatively resistant to salt; yet the biochemical and molecular mechanisms underlying oleander's stress tolerance remain largely unknown. To investigate these mechanisms, one-year-old oleander seedlings were exposed to 15 and 30 days of treatment with increasing salt concentrations, up to 800 mM NaCl, and to complete withholding of irrigation; growth parameters and biochemical markers characteristic of conserved stress-response pathways were then determined in stressed and control plants. Strong water deficit and salt stress both caused inhibition of growth, degradation of photosynthetic pigments, a slight (but statistically significant) increase in the leaf levels of specific osmolytes, and induction of oxidative stress-as indicated by the accumulation of malondialdehyde (MDA), a reliable oxidative stress marker-accompanied by increases in the levels of total phenolic compounds and antioxidant flavonoids and in the specific activities of ascorbate peroxidase (APX) and glutathione reductase (GR). High salinity, in addition, induced accumulation of Na + and Clin roots and leaves and the activation of superoxide dismutase (SOD) and catalase (CAT) activities. Apart from anatomical adaptations that protect oleander from leaf dehydration at moderate levels of stress, our results indicate that tolerance of this species to salinity and water deficit is based on the constitutive accumulation in leaves of high concentrations of soluble carbohydrates and, to a lesser extent, of glycine betaine, and in the activation of the aforementioned antioxidant systems. Moreover, regarding specifically salt stress, mechanisms efficiently blocking transport of toxic ions from the roots to the aerial parts of the plant appear to contribute to a large extent to tolerance in Nerium oleander.

Bu çalışmada pedagojik formasyon eğitimi sertifika programına katılan ve beden eğitimi ve spor öğretmenliği programında öğrenim gören aday beden eğitimi ve spor öğretmenlerinin alana özel öğretim stillerini kullanma tercihleri, düzeyleri ve stillere ilişkin değer algıları öğretmenlik eğitim programı ve cinsiyet değişkenlerine göre incelenmiştir. Araştırmaya pedagojik formasyon sertifika programından 182 öğretmen adayı ve Beden Eğitimi ve Spor Öğretmenliği Bölümü'nün son sınıfında öğrenimlerine devam eden 187 öğretmen adayı katılmıştır. Araştırmada "Beden Eğitimi Öğretmenleri Öğretim Stilleri Değer Algıları Anketi (BEÖÖSDAA)" ölçme aracı olarak kullanılmıştır. Elde edilen veriler betimsel istatistik yöntemleri, MANOVA ve Ki-Kare testleri ile çözümlenmiştir. Her iki grupta da öğretmen merkezli stillerin en yüksek kullanım düzeyine sahip ve en fazla değer verilen stiller olduğu tespit edilmiştir. Katılımcıların cinsiyetlerine göre öğretim stilleri kullanma düzeyi ve stillere verilen değer arasında istatiksel olarak anlamlı fark görülmezken, eğitim görülen program anlamlı fark oluşturmuştur. Katılımcıların öğretim stillerini kullanma tercihleri incelendiğinde ise, öğretmenlik eğitim programlarında yer alan katılımcıların, formasyon sertifika eğitiminde yer alanlara göre "Komut" ve "Alıştırma" stilleri dışında kalan tüm stilleri anlamlı biçimde daha fazla tercih etmişlerdir. Beden eğitimi öğretmeni mesleki gelişimi ve öğretim programlarının etkin biçimde uygulanması açısından öğretmenlik sertifika programlarının alana özel öğretim yöntemlerine yönelik uygulamalara odaklanması ve alan uzmanlarının programlara destek sağlaması önerilebilir.

The aim of this study was to examine attitudes of physical education and sport teacher candidates, studying in physical education teaching program and alternative teacher certification program in Turkey, towards teaching profession. The sample of this study consisted of 172 physical education teacher candidates in alternative teacher education certificate training in the Faculty of Education, and 179 physical education teacher candidates are continuing their education in the department of physical education and sports teacher education in four different universities in Turkey. "Attitude Scale towards Teaching" was used as data collection tool in this study. The data were examined by descriptive statistics and a two-way ANOVA test. The teacher education program has the main effect on attitudes toward teaching and teacher candidates in physical education department demonstrated significantly higher attitudes compared to alternative teacher education program p<0.05. There was an interaction effect of the education program and gender on attitudes, p<0.05. It is suggested that revising the time of the education process in alternative teaching programs and subsidize these programs by field experts may lead to better attitude development among physical education teacher candidates in alternative teaching education certificate.

In our study that we aimed to see the differences between footballers' plantar pressure distribution and sedentary individuals' in total 31 males [(FG)n=19; age=20.66±1.31 years; body length=178.7±4.64 cm; body weight=75,3±6.1kg), 12 sedentary volunteers (n=12; age= 21.05±2.3 years; body length=177.5±4.8cm; body weight=73.55±8.69 kg)] participated. Right, and left foot dynamic plantar pressures were obtained at 100Hz sample speed with the method of 5 steps dynamic walking. The foot was separated into masks by being divided into 14 different pieces. "MH1: 1. M etatarsal head, MH2: 2. M etatarsal head, M H3: 3. M etatarsal head, M H4: 4. M etatarsal head, M H5: 5. metatarsal head, big toe, 2nd toe, 3rd 4th 5th toes, forefoot, mid foot, hind foot and total foot". Peak p ressure (PP-kPa), maximal force (M F-N), contact area (CA-cm2), contact time (CT-ms) M aximal force normalized to body weight (M FNBW) values were calculated for total foot. Whether there are significant differences between the groups were tested with independent sample t-tests by using SPSS 20.0 software. It is seen that statistically significant differences between football and sedentary groups are in the parameters of M H1 left foot peak pressure (

A limited number of acute whole body vibration (WBV) studies have investigated the effects of WBV treatments which were applied with different vibration frequencies and amplitude combinations on lower extremity muscle activation of well-trained athletes from different sports branches. To compare the effects of WBV on lower extremity muscle activation via Surface Electromyography (sEMG) of well-trained athletes from different sports branches (soccer, basketball and swimming) during static and dynamic squat exercises. sEMG activities of Tibialis Anterior (TA), Gastrocnemius Medialis (GM), Vastus Medialis (VM), Rectus Femoris (RF), Vastus Lateralis (VL) and Biceps Femoris (BF) muscles of 7 male soccer players, 7 male basketball players, and 6 male swimmers were recorded during WBV applied in static squat and dynamic squat positions with different frequencies (30-35-40 Hz) and amplitude (2-4 mm) combinations separated from each other by 5 min passive rest periods. Each combination was a...

Background and Study Aim. This study investigates expert and amateur basketball players&#39; visual tracking strategies accuracy and inaccuracy free throws. Material and Methods. A total of 22 university student, 11 of whom were experts (n = 5 females, n = 6 males) and 11 amateurs (n = 5 females, n = 6 males), without visual impairment, participated the study. Each athlete performed a total of 10 throws. The normal distribution of data recorded in both accurate and inaccurate throws was checked with the Shapiro-Wilk test. All of the data received on accurate and inaccurate throws were analyzed by independent samples t-test. Results. Expert basketball players were recorded to have an average of 78% accurate throws out of 10, and as for amateur basketball players, they were recorded to have 34%. During accurate throws, the quiet eye durations of expert basketball players were identified as ~886ms, and quiet eye durations during inaccurate throws were as ~570ms. During accurate throws,...

The purpose of this study was to examine the differences in Ground Reaction Forces (GRF) between standing and running soccer throw-in. Six male amateur soccer players participated in the current study. All data are expressed as mean±SD. The longer distance was observed in the running throw-in than the standing throw-in. The standing throw-in showed higher values at Vertical (Fz) GRF during back swing, forward swing and release phases. However, that of the running throw-in during follow through phase was higher than that of the standing throw-in. As a result, the longer throwing distance in the running throw-in can be explained that the players spend shorter time in all phases at running throw-in than they did in the standing throw-in. This might causes efficient energy transfer from proximal to distal segment during the running throw-in.

The athletic function of the foot is also extremely important in soccer and constantly exposed to the full impact of weight bearing, because it plays a vital role as a contact point with the ground, absorbing abnormal forces, and main area of the body to kick the ball. The purpose of this study was to compare female soccer players and sedentary individuals in terms of plantar pressure distribution while walking and bilateral standing with barefoot. Eleven female soccer players (21.44±2.12 years, 162.25±5.77 cm, 53.12±6.01 kg, BMI=20.23±1.52 kg/m 2 , Experience=5.98±0.78 years) and 14 sedentary individuals (23.38±5.79 years, 164.92±5.88 cm, 56.31±6.56 kg, BMI=20.67±1.78 kg/m 2 ) participated in this study. Participants performed self-paced walking and 30 seconds bilateral standing on a 1.5-meter walking platform with barefoot. Each footprint was divided into 12 areas as total foot, hindfoot, midfoot, forefoot, 1st metatarsal, 2nd metatarsal, 3rd metatarsal, 4th metatarsal and 5th met...

Dual-tasks are often used with postural control. These tasks, which generally target motor skills and cognitive performance, also help to determine the individual’s postural control. The purpose of this study is to determine the changes in performance during the motor task, which includes the cognitive cues of the hearing-impaired athletes. A total of 31 hearing-impaired athletes (male=19, female=12) and 34 hearing-impaired sedentary people (male=18, female=16) were included voluntarily in the study. The FitLight Trainer™ system was used to determine participants’ reaction time levels. The performance time of hearing-impaired male athletes was significantly lower than the hearing-impaired sedentary men in each of the three tests (Random Test: t = 4, 089, p &lt;0.05; Cue Test: t = 3,551, p &lt;0.05; Mixed Cue Test: t = 2, 393, p&lt;0.05). The performance time of hearing-impaired female athletes was statistically significantly lower than that of sedentary hearing-impaired females for ...

The purpose of this study was to examine the differences in Ground Reaction Forces (GRF) between standing and running soccer throw-in. Six male amateur soccer players participated in the current study. All data are expressed as mean±SD. The longer distance was observed in the running throw-in than the standing throw-in. The standing throw-in showed higher values at Vertical (Fz) GRF during back swing, forward swing and release phases. However, that of the running throw-in during follow through phase was higher than that of the standing throw-in. As a result, the longer throwing distance in the running throw-in can be explained that the players spend shorter time in all phases at running throw-in than they did in the standing throw-in. This might causes efficient energy transfer from proximal to distal segment during the running throw-in.