Relationship between Isokinetic Knee Strength and Speed, Agility, and Explosive Power in Elite Soccer Players

The aim of this study was to determine the relationship between the isokinetic characteristics of knee extensors and flexors with selected motor abilities: Speed, agility, and explosive power of lower extremities of professional football players in the preparation period of a yearly training cycle. Twenty-one players (age: 24.5 ± 3.9 years; body mass: 76.7 ± 4.7 kg and body height: 183.5 ± 5.5 cm) playing in the highest Polish soccer league participated in the study. The isokinetic concentric torque of the knee extensors and flexors was measured at 300°/s, 180°/s, and 60°/s velocities. Sprint performance was assessed in the 30 m sprint test (standing start). The forward, lateral, and backward movements were assessed using the T-Test of agility. Explosive power was quantified by performing the squat jump (SJ) and countermovement (CMJ), using the force platform. Due to sport-specific demands of soccer activities measured in this experiment, the relationships between peak torque (PT) and the 30 m sprint, T-Test of agility, and power of vertical jumps (SJ and CMJ) were low or medium at speeds of 60°/s and 300°/s. One of the main reasons for the lack of high dependence of the above-mentioned factors are that the measurements were performed during the initial training period where the level of individual abilities is at a low level. Additionally, this experiment may also indicate that the measurement of isokinetic knee flexion and extension peak is effective when performed at the correct angular velocity in relation to the evaluation of the intended motion structure.

The influence of special physical fitness of athletes on the level of technique of playing beach volleyball

Background and Study Aim. Aim is to determine the influence of the components of special physical training on the effectiveness of certain elements of the game technique during the competitive activities of beach volleyball athletes. Material and methods. The study involved athletes (n = 20, age - 17-21 years, experience - 8-9 years), who are engaged in beach volleyball (Kherson, Ukraine). Experts (n = 5, work experience - over 20 years) from among the leading volleyball specialists were involved. Training sessions were conducted according to the author’s structure and content of special physical training (preparatory period of the annual cycle). The author's program was to increase the volume of athletic work by 10% (selective classes and integrated work) and 17% (complex classes). The classes used a developed special training device. The device is designed to practice practical game skills. The load at the first stage was 70-80% of the maximum. The load in the second stage was 80-90% of the maximum. Results. Significant (p <0.05) development of explosive power, speed and agility was revealed. There is a significant (p <0,05) increase: in the number of jump serve and spike; improving the quality/number of serve and attack; improving the quality of passing and the number of blocks. Conclusions. The proposed structure and content of special physical training and exercises on a special simulator have significantly increased the level of development of physical qualities. The athlete training program helped to improve the effectiveness of certain technical actions during competitive activities.

The influence of motor skills on the short sprint results

Background and Study Aim. The curriculum of physical education in high schools is based on learning motor skills, as well as their development in sports sections, where the 100-meter sprint dominates. The aim of the study was to determine the influence of motor skills on the 100 m running results. Material and Methods. The research was conducted on a sample of 80 high school students in Novi Pazar and Kraljevo, aged 16 and 17 years (± 6 months). 12 variables were used to assess motor skills, three variables each: explosive power, segmental speed, repetitive power, and flexibility (standing long jump), triple jump, five jumps. For estimating segmental speed: foot tapping, hand tapping, foot tapping on the wall. For the assessment of repetitive power: lifting the torso on the Swedish bench, mixed pull-ups, squats. To assess flexibility: deep bench press, twine, stick twist. Results. Results were obtained to confirm that there is a positive influence of motor skills on the 100 m sprint results at the level of (p=.000). The results in the 100 m sprints are statistically significantly dependent on the motor skills that manifest segmental speed and explosive power. Variables (standing long jump, foot tapping on the wall and foot tapping) have a statistically significant effect on the criterion variable of the 100 m sprint. Conclusions. Recommendation to future researchers would be to conduct a study over a longer period of time with the aim of examining the biomechanical factors that determine the success in sprint, is the production of force in the phase of sprint acceleration and sprint deceleration.

The effect of whey protein on malondialdehyde, aerobic capacity, and leg muscle explosive power in basketball athletes

Background: High-physical activity, including aerobic capacity and leg muscle explosive power, can cause stress oxidative and decrease the performance of athletes. Whey protein contains essential amino acids that were beneficial to decreased malondialdehyde (MDA) levels.Objective: To analyze the effect of whey protein on MDA level, aerobic capacity, and leg muscle explosive power in basketball athletes.Materials and Methods: Randomized controlled trial using pre- and post-test design was conducted on 12 male athletes aged 16-18 years at PPLOP Central Java Basketball Club. The treatment group received 30 grams of whey protein, and the control group received 30 grams of chocolate powder as a placebo for 28 days. MDA levels were measured through Elisa methods. Aerobic capacity was measured by 20 meters sprint. Leg muscle explosive power was measured by vertical jump. Data were analyzed by an independent t-test.Results: The mean MDA levels before intervention in the whey protein group were 182.36 (±59.05), and the mean after the intervention was 171.83 (±5.46). The mean before the aerobic intervention capacity was 36.95 (±5.84), and the mean after the intervention was 49.75 (±3.53). The mean leg muscle explosive was 83.50 (±21.58), and the mean after the intervention was 87.33 (±16.68). There were no effect of whey protein on MDA levels (p>0,05), aerobic capacity (p>0,05) and leg muscle explosive power (p>0,05).Conclusion: Whey protein for 28 days had no effect on MDA levels, aerobic capacity, and leg muscle explosive power

Hubungan Antara Umur, Jenis Kelamin, Indeks Massa Tubuh, Lama Latihan Dengan Daya Ledak Otot Tungkai Pada Atlet Taekwondo

Taekwondo is a martial sport that relies on kicks. For a taekwondo athlete to kick, it is necessary to support the explosive power of the leg muscles. This study aims to analyze the relationship between age, sex, body mass index, length of exercise with leg muscle explosive power in taekwondo athletes. Subjects and Methods: This analytic descriptive study used a cross sectional design. The subjects of the study were taekwondo members at Sangkuriang Sports Hall and Lions Gymnasium in Cimahi City, West Java Province, totaling 95 people. The dependent variable is leg muscle explosive power. The independent variables were age, gender, body mass index and duration of exercise. The instruments used are questionnaires and vertical jump measuring instruments. Data were analyzed bivariately using OR and chi square test. The explosive power of the limbs increased with increasing age (OR= 2.89; 95% CI= 1.23 to 5.77; p= 0.010) and duration of exercise (OR= 7.44; 95% CI= 2.96 to 18.67; p <0.001). Leg explosive power decreased with body mass index but not statistically significant (OR= 0.72; 95% CI= 0.30 to 1.18; p= 0.600). Gender increased limb explosive power, but not statistically significant (OR= 1.14; 95% CI= 0.51 to 2.56; p= 0.900). The explosive power of the limbs increases with age and duration of exercise. The relationship between limb explosive power and sex and body mass index was not statistically significant

HUBUNGAN DAYA LEDAK OTOT TUNGKAI DENGAN KEMAMPUAN SMASH PADA EKTRAKURIKULER BOLAVOLI DI SMP NEGERI 6 KOTA LUBUKLINGGAU

The problem in this study is that volleyball extracurricular students at SMP Negeri 6 Lubuklinggau City still have jumps and punches in the weak category, this is due to the weak power of the students' leg muscles which causes the smash to be performed less than optimal. The research objective was to determine whether there was a relationship between the explosive power of the leg muscles and the smash ability of volleyball players at SMP Negeri 6 Lubuklinggau City. The variables of this study were the leg muscle explosive power as the independent variable, and the smash ability was the dependent variable. This type of research is correlational research. This research was conducted on 14 male volleyball extracurricular students at SMP Negeri 6 Lubuklinggau City. The instrument for collecting the explosive power of the leg muscles used the vertical jump test and the smash used the smash ability test. The data analysis technique used the product moment correlation formula. The results of the study showed that there was a relationship between the leg muscle explosive power (x) and the volleyball smash ability (y), the calculation result was rxy = 0.55 from this value can be categorized as moderate. The results stated that there was a significant relationship between the explosive power of leg muscles on the smash ability of volleyball extracurricular students at SMP Negeri 6 Lubuklinggau City, this was stated based on hypothesis testing where t hit = 2.280 > t tab = 2.178.

HUBUNGAN DAYA LEDAK OTOT TUNGKAI TERHADAP KEMAMPUAN LOMPAT JAUH MAHASISWA PENJASKESREK STKIP-PGRI LUBUKLINGGAU

This study aims to determine the relationship between limb muscle explosive power and the long jump ability of STKIP-PGRI Lubuklinggau students. This research is a correlational study. The population in this study was the 3rd semester of Physical Education and Health students in the 2020 Academic Year STKIP-PGRI Lubuklinggau. The sample used is 30 students. The research method used is correlation, with data collection techniques using tests and measurements. The instrument for measuring the explosive power of the leg muscles uses the standing broud jump test and for the long jump ability using the long jump test. The data analysis technique uses normality, linearity, and product moment correlation tests using SPSS (Statistical Program For Social Science) for windows software. The results showed that: There was a significant relationship between the explosive power of the leg muscles and the long jump ability of the Physical Education students at STKIP-PGRI Lubuklinggau, with the value of rcount = 0.544 > r table = 0.361. With the contribution of leg muscle explosive power to the long jump ability of the 3rd semester physical education and health sector students in the 2020 Academic Year of STKIP-PGRI Lubuklinggau, amounting to 29.6%. Then the alternative hypothesis is accepted.

Inducing low energy availability in trained endurance male athletes results in poorer explosive power

Purpose Low energy availability in males needs more original research to understand its health and performance consequences. The aim of the study was to induce low energy availability in previously healthy male endurance athletes by reducing energy availability by 25% for 14 consecutive days and measure any potential changes in performance, health, mental state or energy markers. Methods Energy availability was reduced in 12 trained, well-trained and elite endurance athletes by increasing energy expenditure and controlling energy intake. After intervention, health was assessed by blood draw, body composition was measured, energy markers by measuring resting energy expenditure, performance with three specific tests (measuring endurance, agility and explosive power) and two questionnaires were used for psychological assessment (the Three Factor Eating Questionnaire and Well-being questionnaire). Results Reduced energy availability (22.4 ± 6.3 kcal/kg FFM/day) caused significantly lower haemoglobin values (t(12) = 2.652, p = 0.022), there was a tendency for lower iron and IGF-1 (p = 0.066 and p = 0.077, respectively). Explosive power was reduced (t(12) = 4.570, p = 0.001), lactate metabolism was altered and athletes reported poorer well-being (t(12) = 2.385, p = 0.036). Cognitive restriction was correlated with energy availability (r = 0.528, p = 0.039). Conclusion This is the first research providing direct evidence that suboptimal energy availability negatively impacts explosive power before hormonal changes occur in male endurance athletes. It is also the first to show direct association of low energy availability and higher cognitive restriction. We also observed worse well-being and lower haemoglobin values. 25% of energy availability reduction as not enough to elicit changes in resting energy expenditure.

Pengaruh Explosive Power Otot Tungkai Dengan Hasil Lompat Jauh Gaya Jongkok Siswa Kelas X Ips Sma Muhammadiyah Kabupaten Kampar

Based on the observations made by the author in Class X Social Studies at SMA Muhammadiyah Kampar Regency, it was found that the ability of students to do long jumps was still in the below-average category. This is due to the low physical condition of students so that they do not produce maximum explosive power of the leg muscles. This research was conducted using a correlational research design. Based on the results of research that has been carried out on class X students of SMA Muhammadiyah Kampar Regency, the value of count = 0.811 > table = 0.514. Obtained r = 0.811 including very strong category. Significance test using the t-test Significance formula. From the calculation results, it is known that t count = 5,006 while t table = 1,771. So t count = 5,006 > t table = 1,771. Thus, a conclusion can be drawn that: There is an effect of explosive power in the leg muscles with the results of the long jump squatting style for X grade students of SMA Muhammadiyah Kampar Regency. Conclusions. Based on the results of research that has been carried out on class X students of SMA Muhammadiyah Kampar Regency, the value of count = 0.811 > table = 0.514. Obtained r = 0.811 including very strong category. Significance test using the t-test Significance formula. From the calculation results, it is known that t count = 5,006 while t table = 1,771. So t count = 5,006 > t table = 1,771. Thus, a conclusion can be drawn that: There is an effect of explosive power in the leg muscles with the results of the long jump squatting style for X grade students of SMA Muhammadiyah Kampar Regency

Hubungan antara Detraining Selama Pandemi Covid-19 dengan Kemampuan Daya Ledak Otot Tungkai Atlet UKM Karate

Karate is one of the most popular martial arts practiced around the world. Karate training puts a great deal of stress on the peripheral joints, and the rotational motion of the spine can greatly affect their mobility. Explosive power is needed in the sport of karate because explosive power is a support in every karate technique movement. Someone who stops exercising for 2-4 weeks will experience a decrease in physiological functions of the body or can be called detraining. The purpose of this study was to determine whether there was a relationship between detraining during the Covid-19 pandemic against the leg muscle explosive power of athletes of Karate UKM State University of Malang. The research is a quantitative correlational study with a causal design. In this research, the sample used is athlete karate State University of Malang as many as 19 people. The data collection method used According to the research, there is a relationship between detraining explosive muscle leg athletes ukm karate Universitas Malang with a p-value is 0.000 less than α is 0,05 and Value correlation coefficient obtained by 0.886. Research concludes that there is a relationship between detraining during the Covid - 19 pandemic on the leg muscle explosive power of SMK karate athletes, State University of Malang. Abstrak: Karate merupakan salah satu beladiri yang paling populer dipraktikkan di seluruh dunia. Pelatihan karate memberikan tekanan yang besar pada sendi perifer, dan gerakan rotasi tulang belakang dapat sangat mempengaruhi mobilitasnya. Daya ledak sangat dibutuhkan dalam olahraga karate dikarenakan daya ledak merupakan penunjang dalam setiap gerakan teknik karate. Seseorang yang berhenti latihan selama 2-4 minggu akan mengalami penurunan fungsi fisiologis terhadap tubuh atau bisa disebut detraining. Tujuan dari penelitian ini adalah untuk mengetahui apakah terdapat hubungan antara detraining selama pandemic Covid-19 terhadap daya ledak otot tungkai Atlet UKM Karate Universitas Negeri Malang. Penelitian ini merupakan penelitian kuantitatif korelasional dengan desain sebab akibat. Dalam penelitian ini, sampel yang digunakan merupakan atlet karate Universitas Negeri Malang sebanyak 19 orang. Metode pengambilan data menggunakan Berdasarkan hasil penelitian, terdapat hubungan antara detraining dengan daya ledak otot tungkai atlet ukm karate Universitas Negeri Malang dengan p-value sama dengan 0,000 kurang dari α sama dengan 0,05 dan Nilai correlation coefficient yang didapatkan sebesar 0,886. Penelitian ini menyimpulkan bahwa terdapat hubungan antara detraining selama pandemic Covid- 19 terhadap daya ledak otot tungkai atlet ukm karate Universitas Negeri Malang.