Motricidade

Comparative Studies for What?

Effect of imagery on free throw performance in young basketball players

O objetivo da pesquisa foi analisar o efeito do treino mental sobre o desempenho do arremesso de lance livre em jovens atletas de basquetebol. A amostra foi composta por 33 voluntários com idades compreendidas entre os 14 e 15 anos, divididos aleatoriamente em dois grupos: experimental (GE, n = 16) e controle (GC, n = 17). Ambos os grupos (GE e GC) fizeram a mesma planificação de treino físico/técnico no decorrer das 8 semanas. O GC assistiu vídeos sobre história das olimpíadas, ao passo que o GE realizou o treino mental. Foram realizadas 3 sessões semanais de treino mental intercaladas com o período de 48 horas. O desempenho no arremesso de lance livre (percentual de acerto) foi mensurado antes e após as 8 semanas. Os resultados apresentaram efeitos de tempo (F(2, 31) = 19.65, p = .01) e grupo (F(2, 31) = 40.09, p = .001). Foi identificada diferença significativa do desempenho no arremesso de lance livre entre GE e GC após as 8 semanas (F(2, 31) = 43.13, p = .01, d = .5). Assim, concluiu-se que o treino mental foi eficiente para maximizar o desempenho no arremesso de lance livre de jovens atletas de basquetebol.

The purpose of the present study was to analyze the effect of imaginary training on the free-throw performance in young basketball players. The sample consisted of 33 volunteers aged between 14 and 15 years, divided randomly into two groups: experimental (EG, n = 16) and control (CG, n = 17) group. Both groups underwent the same physical/technical training plan during eight weeks. The CG watched videos on the history of the Olympic Games, while the EG performed the imaginary training 3 times for week interspersed with the period of 48 hours. Performance in free-throw (hit percentage) was measured before and after 8 weeks. The results presented time (F(2, 31) = 19.65, p = .01) and group (F(2, 31) = 40.09, p = .001) effect. It was identified significant differences in free-throw performance between EG and CG after 8 weeks (F(2, 31) = 43.13, p = .01, d = .5). Thus, it was concluded that imaginary training was efficient to maximize free-throw performance in young basketball players.

Effects of Tested Rules on Work-Rest Time in Volleyball

The aim of this study was to determine the influence of new rules tested at the inaugural Mens Under 23 (U23) World Championship (set to 21 points and 15 seconds between the end of a point and the new serve) on all aspects of time in volleyball matches. The study sample comprised 36 matches partially segmented into 123 sets and 4583 points played. Applying one-way ANOVA, it was shown that the active part of the set and the whole match last slightly more than one third of the total time. The most frequent rally duration was 5 to 10 seconds (43.5% of points). As sets became more unpredictable and approached the end, rest time between points was longer. Time analysis of volleyball matches is important as it helps with proper development of physical preparation for players, gives coaches insight into appropriate match flow and provides a clear time frame of each part of a volleyball match for organisers of competitive events, pools, championships and tournaments.

Prevalence of Developmental Coordination Disorder signs in children 5 to 14 years in São Carlos

This study aimed to identify the prevalence of Developmental Coordination Disorder (DCD) in children aged 5-14 years, enrolled in public preschools and elementary schools in São Carlos - SP. There were 130 participating families. Instruments were: Developmental Coordination Disorder Questionnaire - Brazil (DCDQ - Brazil), Brazil criteria and a questionnaire for the characterization of children. The prevalence of DCD found was 30%, which is overestimated when compared to data found in much of the literature, justified by the use of the instrument for detection of the DCD. No significant difference was found between the presence of signs in boys and girls and there was a higher concentration of children with DCD signs on B2, C1 and C2 socioeconomic classes. The prevalence of DCD signs was higher in children over 8 years.

Hemodynamic responses to strength exercise with blood flow restriction during different phases of the menstrual cycle

The present study aimed to determine the influence of low-load (LL) resistance exercise (RE) with blood flow restriction (BFR) on systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), heart rate (HR), double product (DP) and oxygen saturation (SpO2) during the phases of the menstrual cycle (MC). Thirty untrained women were randomly and proportionally divided into three groups: HI = high-intensity exercises (80% of one-repetition maximum (1RM)); LL = low-load exercises (20% of 1RM); and LL+BFR = LL exercises combined with BFR. The exercise sessions were performed during the 3rd-4th days (follicular phase), 16th day (ovulatory phase) and the 24th-26th days (luteal phase) of the MC. Before and immediately after the exercises, SBP, DBP, HR and SpO2 were evaluated. We observed an increase in SBP, HR and DP in the three phases of the MC for all groups (p < 0.05). Groups LL and/or LL+BFR exhibited a greater increase in SBP, DBP, MBP, HR and DP when compared with the HI group (p < 0.05), and in the three groups, SpO2 was not reduced (p > 0.05). There was a significant effect of the MC phases on HR and DP (p < 0.05). We conclude that the three groups exhibited increased SBP, HR and DP; however, SpO2 was not different. Furthermore, groups LL and LL+BFR exhibited greater increases in hemodynamics, and the MC phases seem to influence only HR and DP.

Fitness, cardiovascular and metabolic risk factors: A correlational study

This study aimed to verify the relationship between anthropometric measures (AM), blood pressure (BP) and cardiorespiratory fitness (CRF), physical activity (PA), sedentary behaviour (SB), predicted BMI z-score, waist circumference (WC) and waist-to-height ratio (WHtR) variance. A total of 245 children (8.90 ± .80years-old) were recruited from a Portuguese school. WHtR was classified according the reference ≥ 0.5. WC was measured above iliac crest. BP was assessed using a sphygmomanometer, and CRF using 20-m run test. PA and SB were assessed by accelerometers (Actigraph GT3x) and by questionnaire. Participants did not meet recommendations on PA. CRF and vigorous PA (VPA) were inversely correlated with AM. Moderate and vigorous PA were positively correlated with CRF. CRF was inversely correlated with systolic and diastolic BP. CRF and PA explained BMI z-score variance. WC and WHtR variance was predicted by CRF. These results emphasize the importance of international recommendations for PA with the purpose of developing CRF. A new emphasis should be given to CRF and interdisciplinary approaches in international recommendations. This should provide new health implications for primary care providers and school services.

Hepatic glycogen levels in female rats submitted to aquatic therapy after muscle disuse

The aim of the present study was to analyse the changes in liver glycogen content in rats subjected to aquatic therapy post-disuse of the paw. 32 wistar adult female rats were equally divided: Control (C), kept in the cage for two weeks without interventions; Disuse (D) had the right paw immobilized with hip extension, knee and plantar flexion for two weeks; Aquatic Therapy (AT) underwent aquatic therapy with increments of 3 minutes daily for two weeks, totalizing 36 minutes of training; Disused Aquatic Therapy (DTA) was first subjected to immobilization for two weeks and 24 hours after withdrawal of immobilization aquatic therapy was started for two more weeks, in same protocols of D and AT groups. At the end of the experiment, the animals were sacrificed, and tissues were dissected, weighed and stored. The liver tissues were referred analysis of glycogen content. It was observed that the blood glucose levels of the AT group (104 mg/dL) were different from the C group (86 mg/dL; p = 0.0213). Regarding hepatic glycogen, the D (2.35mg±0.07) and AT (2.73mg±0.07) groups had hepatic glycogen reduction by 22% and 15%, relative to C (2.51mg±0.03); p <0.0001). The DTA group presented no differences when compared to the control, suggesting the normalization of the finding. Muscle disuse by two weeks promoted changes in glycogen levels, however, two weeks after disuse condition, the aquatic therapy were able to correct the energetic reserve in liver.

Morfofunctional parameters in judo's fight

Considering the complexity of judo and the ample energy and neuromuscular demands, a whole process of competitive preparation must be directed to different physical capacities allowing the athlete to perform his combat actions with the best suitability possible. Mapping the behaviour of a judo athlete from observations of behaviour units in a real fighting situation would be a way of trying to identify the best topography or the best "aptitude" to achieve victory. The present investigation analysed the judo from the interactions of a real competition situation, aiming to verify, between winners and losers, possible differences or correlations between anthropometric parameters, motor performance and functional behaviours in a competitive situation. The results showed that: a) the experience is decisive between winning or losing; b) leg techniques are the most used between winners and losers, and losers use them more frequently; c) there are different strategies between fights; d) The energy cost in judo depends on the configuration of the fights. It is believed that such results can help coaches and athletes in guiding and rationalizing the training process in relation to performance determinants in judo.

Chronic effects of exhausting exercise and overtraining on the immune response: T_h1 and T_h2 profile

Although physical inactivity figures as one of the main causes attributed to mortality, the damage caused by excessive exercise is also a reality. Professional athletes, amateur or uncompetitive modalities beneficiaries are often affected by deleterious conditions resulting from excessive exercise, such as neurological, endocrine and immune origin. The thin line between losses and benefits of successive fatiguing sessions effort depends on the understanding of concepts and methodological training principles. Exercise may have a paradoxical relationship and its consistent prescription in terms of public health depends on a better understanding of their cellular mechanisms. In this sense, the purpose of this review was to explore a promising topic in sports science, able to contribute to elucidate such mechanisms: Th1 and Th2 profile of the immune response related with chronic exhausting exercise and overtraining.