Improving the process of how physical performance is enhanced is one of the main topics evaluated by physiologists. This process often involves athletes and nonathletic populations. The purpose of this study was to assess the chronic response to 10 weeks of static stretching exercises carried out before and during a strength training program for 8 exercises on an 8 repetition maximum (8RM) test performance, and basal serum insulinlike growth factor (IGF-1) levels. Thirty recreationally trained volunteers were randomly assigned to 1 of 3 training groups: (a) SBST (performed a warm-up with a static stretching protocol before each strength training session); (b) SDST (before each training set, a static stretching exercise was performed); and (c) OST (entire session was performed without any type of stretching exercise). Strength and IGF-1 levels were collected at the beginning (pretest) and end (posttest) of the entire experimental procedure. All the exercises showed a significant increase in muscle strength for the OST group. However, the results revealed a significant increase in the muscle strength for only a few exercises in the SBST (LP, LE) and SDST (LP) experimental conditions. Significant statistical differences were found between SBST and SDST for all the exercises in the OST experimental condition. Furthermore, the IGF-1 expression showed no significant differences in the intragroup analysis. However, the OST group showed higher values (p < 0.05) in the posttest when compared with those of the other groups (increased significantly only in the OST experimental condition). It has been concluded that, although all the groups showed an increase in muscular strength, the strength training performed without any type of stretching exercise, regardless of whether the stretching is performed before or during the lifting session, can more effectively increase muscle strength and basal serum IGF-1 levels. It was concluded that strength training, with or without the use of stretching exercises, increased muscular strength in the studied groups, and can induce an increase in IGF-1 levels.

No abstract

RESUMOO objetivo deste estudo foi comparar a influência aguda do alongamento estático sobre a força muscular máxima (1RM). A amostra não probabilística foi constituída de 30 indivíduos divididos em dois grupos: grupo alongamento estático (GA= 15) e grupo sem alongamento (GC= 15). Para avaliação da força muscular através do teste de 1RM foi utilizado um dinamómetro modelo 32527pp400 Pound push/pull acoplado nos aparelhos cadeira extensora (CE) e supino reto/horizontal (SH). Utilizou-se o teste de Wilcoxon para as comparações intragrupos e o teste de Kruskal-Walis para as comparações intergrupos (p< 0.05). Não foram observadas diferenças estatisticamente significativas (p> 0.05) entre o GA e o GC para o exercício CE e SH. Pode-se concluir que não houve redução no desempenho do teste de 1RM para os exercícios CE e SH, quando precedidos por alongamento estático. Palavras-chave: força muscular, alongamento, alongamento estático ABSTRACTThe aim of this study was to compare the influence of acute static stretching on maximal muscle strength (1RM). The non-probabilistic sample consisted of 30 subjects split into two groups: static stretching (SS= 15) and without stretching group (WS= 15). Muscle strength evaluation (1RM) was conducted with a Dynamometer model 32527pp400 Pound push / pull devices coupled in knee extension (KE) and bench press (BP). The Wilcoxon test for intragroup comparisons and the Kruskal-Wallis test for comparisons between groups (p< 0.05) were selected. There were no significant differences (p> 0.05) between the SS and WS in exercise KE and BP. Therefore, it can be concluded that there was no reduction in the performance of 1RM performing the exercises KE and BP when preceded by static stretching.

Silva JLB, Saraiva AR, Monte Júnior GC, Portal MND, Lima JRP, Dantas EHM. Physical qualities of 13-year-old scholars who went through traditional sportive formation Fit Perf J. 2009 Nov-Dec;8(6):400-6. ;8(6):400-6. ABSTRACTIntroduction: This study had as objective to evaluate the effects of traditional methodology of sportive formation regarding the physical qualities of 13-year-old scholars, who went through a 16-week intervention. Materials and Methods:The sample consisted of 40 scholars divided into two groups (GT=20 and GC =20), as the coordination (Burpee test), explosive strength (vertical impulsion), aerobic resistance and agility (Shuttle Run test), velocity (50m) and flexibility (goniometry) were evaluated. The statistics were descriptive and inferential (t test, Wilcoxon, Kruskal Wallis and Mann-Whitney) with p≤0.05. Results: Intergroup comparisons did not present statistically significant differences; however, in the intragroups comparisons, we found differences with regard to the explosive strength (∆%=6.85; p=0.000), coordination (∆%=13.64; p=0.000), velocity (∆%=-3.58; p=0.002), aerobic resistance (∆%=7.44; p=0.000) and flexibility EAQ (∆%=10.59; p=0.000). The same did not occur with GC. Discussion: The results showed that the use of a traditional methodology was not effective for the development of physical qualities of 13-year-old schoolchildren.

SummaryStudy aim: To compare two exercise training modes on the physical fitness of 10 year-old children. Material and methods: A sample of 60 schoolboys aged 10 years were randomly divided into 3 groups: Traditional (TG), trained according to the Brazilian national curricular parameters, Maturational (MG), in which the degree of difficulty of the activities was adjusted to the level of maturity of subjects, and Control group (CG). The GreulichPyle protocol was used to assess biological maturity. The following fitness tests were applied: 5×10 m shuttle run (SHR), Burpee's test (BCT), goniometric (LABIFIE) measurement of shoulder joint flexibility (SAA), horizontal shoulder flexion (HSF), shoulder joint abduction (SJA), lumbar spine flexion (LSF), hip joint extension (HJE) [10], Sargent's Jump Test (SJT), endurance shuttle run (ESR) and 50-m run. The TG and MG groups trained 16 weeks, twice weekly. Results: The only significant (p<0.05) between-group differences were found for SJA (TG >MG) and LSF (TG >CG). Conclusions: Despite the lack of clear-cut results, biological maturation combined with chronological age should be considered when applying various methodological approaches in order to encourage the engagement in physical exercises as this would have favourable carry-over effects.