Jurandir Baptista da Silva

Anthropometric and physical fitness parameters versus specific performance tests in Brazilian field hockey athletes: a pilot study

Summary Study aim: To investigate the correlation between anthropometric parameters, Sargent jump test, core muscles endurance and agility performance versus specific tests with and without a ball in female Brazilian field hockey athletes. Material and methods: Nine professional female field hockey players (age: 27.4 ± 2.5 years) participated in this study. Body height, body weight, body fat percentage, Sargent jump test (SJT), shuttle run agility test (SR), core muscular endurance tests and sport-specific tests - repeated sprint ability test (RSA) and repeated sprint ability with the ball (RSAB) - were assessed in a randomized order. Results: A moderate correlation was noted between SR and RSAB (r = 0.58, p = 0.09) and RSA (r = 0.60, p = 0.08). In addition, a moderate correlation was noted between percentage of body fat with RSAB (r = 0.59, p = 0.09) and with RSA (r = 0.72, p = 0.08). The other variables showed slight agreement or no agreement. Conclusions: These results indicated that the SR could be implemented in training and evaluation programs of hockey athletes due to the correlation with specific tests. Thus, the percentage of body fat was the only anthropometric parameter that showed a correlation with the specific tests, revealing the importance of maintaining a proper percentage of body fat for better performance in hockey.

Electromyography Activation of the Lower Limb Muscles Adopting Physioball and Elastic Band to Stabilize Knee Joint During Multiple Sets With Submaximal Loads

STUDY DESIGN Crossover design. CONTEXT Excessive valgus and varus force which affected the knee joint during dynamic tasks has been often associated to lower extremity injuries. Strategies to increase the resistance against these asymmetries (eg, the use of a physioball between the knees or elastic bands around the knees) are often applied in rehabilitation and conditioning programs. OBJECTIVE The purpose of this study was to investigate the effect of performing leg press (LP) 45° using a physioball and elastic band over multiple sets with submaximal loads on electromyographic (EMG) amplitude and fatigue indices. METHODS 18 trained females volunteered (age: 24.4 ± 2.1 y; height: 168.1 ± 4 cm; body mass: 65.1 ± 4.4 kg) participated in this study. The 10 repetition maximum (RM) loads were determined for the LP. Then, 3 experimental protocols were followed in a randomized crossover design over 3 nonconsecutive days: control protocol-the participants performed 4 LP sets; physioball between knees-4 LP sets were performed with the physioball between the knees; elastic band-4 LP sets were performed with the elastic band involving the knees. Ten repetitions were performed during each set with 70% of 10-RM loads; EMG spectral indices (CRMS and Cf5) was collected from the biceps femoris (BF), vastus lateralis (VL), vastus medialis obliquus (VMO), and rectus femoris (RF) muscles. RESULTS Higher levels of CRMS and Cf5 were noted for RF, VL, and VM muscles using the physioball and elastic band when compared with control protocol, respectively. CRMS index of BF muscle was significantly higher using physioball and elastic band protocol versus control condition, respectively. CONCLUSION Therefore, both physioball and elastic band can be adopted during LP with the goal to reduce excessive varus and valgus forces, respectively, even performing consecutive sets with submaximal loads. Furthermore, this may be an interesting alternative to increasing quadriceps activation and improving the knee joint stabilization.

Lombalgia em professores de musculação da zona oeste da cidade do Rio de Janeiro

JUSTIFICATIVA E OBJETIVOS: A dor lombar e um dos sintomas musculoesqueleticos mais comuns nas sociedades industrializadas, de acordo a Organizacao Mundial de Saude. O objetivo do estudo foi investigar a prevalencia de dor lombar em professores que atuam na atividade de musculacao em academias de ginastica no municipio do Rio de Janeiro e verificar as correlacoes entre idade, tempo de trabalho, horas de trabalho e intensidade da dor lombar. METODOS: Foi aplicado o Questionario adaptado do Quebec Pain Disability Scale em 50 professores de Educacao Fisica de ambos os generos (idade=31,86±6,86 anos) que trabalham na musculacao em academias de ginastica, com jornada semanal minima de 12h de trabalho, e ao menos tres anos de atuacao pratica na area. O trabalho foi caracterizado como um estudo descritivo, de corte transversal do tipo Survey. RESULTADOS: Dos 50 professores entrevistados, 62% alegaram nao sentir qualquer tipo de desconforto na regiao lombar, enquanto apenas 38% afirmaram sentir algum tipo de dor. Desses, 20% alegaram que a manifestacao da dor e diaria, 6% semanal e 12% relataram que as dores sao mensais. Sobre a intensidade da dor em seu pior momento, 14% afirmaram ser suave, 20% moderada e apenas 6% relataram dores intensas. Observou-se correlacao positiva e significativa (p<0,05) entre a idade e tempo de trabalho e entre tempo de trabalho e intensidade da dor lombar. CONCLUSAO: A prevalencia de dor lombar nao foi alta nos profissionais pesquisados da amostra. Os resultados apontam que os individuos com mais idade e que possuem mais tempo de trabalho sao os que apresentam dor lombar em niveis mais elevados.

Determination and comparison of time under tension required to perform 8, 10 and 12-RM loads in the bench press exercise

Summary Study aim: To determine and compare the time under tension (TUT) required to perform 8, 10 and 12 repetition maximum (RM) loads in the bench press exercise. Material and methods: Twenty men (24.17 ± 4.69 years) were selected intentionally and properly. We included in the study physically active individuals, with a weekly frequency of physical activity of at least two days for six months, and excluded individuals with injury or pain that could interfere with the correct execution of the exercise and individuals with positive PAR-Q. The 10-RM test consisted in performing ten consecutive repetitions with maximum overload and the highest speed in bench press exercise on the Smith machine. After 48 h, 10-RM sets were performed with the load obtained in the 10-RM load testing. The TUT in 10-RM was verified through kinematics using the timing technique of the Kinovea software. Results: The RM loads and TUT obtained during the retest session showed normal distribution between subjects. However, no significant differences were found between the loads 8, 10 and 12-RM within and between subjects (p < 0.05). The verified TUT showed a difference from 8 to 10-RM and from 8 to 12-RM, but no significant difference was found between TUT protocols for 10 and 12-RM (p < 0.05). Conclusion: The study results enable evaluation of TUT in bench press exercise on the Smith machine for the study sample, allowing, for this group, the prediction and control of training intensity through the TUT.