Effects of photobiomodulation applied at different times on functional performance and ergogenic response of rugby athletes: Randomized clinical trial.

BACKGROUND: Photobiomodulation (PBM) is indicated to accelerate the recovery of athletes and reduce muscle damage caused by physical exercise. The objective of this study was to establish the best time to apply photobiomodulation to increase the functional performance and ergogenic response of rugby athletes. METHODS: Randomized crossover clinical trial with 18 rugby athletes of both sexes. The interventions were carried out from January to May 2019. The blood levels of creatine kinase (CK) and lactate, and performance in the Modified Star Excursion Balance Test, Single Hop Test, Triple Hop Test, Bangsbo Sprint test (BST), and Yo-Yo intermittent recovery level 1 (YoyoIR1) were evaluated. The athletes underwent two blocks of exercises with the BST and Yoyo-IR1, as well as the random application of four interventions: without application of photobiomodulation (CO), pre-exercise photobiomodulation (PBpre), PBM during the exercise interval (PBint), or post-exercise photobiomodulation (PBpos). The photobiomodulation using light-emitting diodes (850 nm, 8 J/cm2) lasted 10 min and was applied to the quadriceps, hamstrings, and triceps surae muscles. The results were compared between groups and times, and the effect size for the interventions was established. RESULTS: No differences were found between groups in CK, lactate, and performance in the functional tests between groups and times. Only the PBpre presented improved performance in the first Yoyo-1R1 test (p < 0.01), while the PBint improved in the second Yoyo-IR1 test and BST (p < 0.05). CONCLUSION: The PBM did not change muscle damage markers or performance in the functional tests. For an ergogenic response, photobiomodulation applied before exercise improves performance, which can be maintained when PBM is performed in the exercise interval.

Effect of resistance training with different frequencies and detraining on muscular strength and oxidative stress biomarkers in older women.

The aim of this study was to compare the effect of resistance training (RT) performed with different frequencies followed by a detraining period on muscular strength and oxidative stress (OS) biomarkers in older women. Twenty-seven physically independent women (68.8 ± 4.8 years, 69.1 ± 14.3 kg, 156.0 ± 6.5 cm, and 28.3 ± 4.9 to kg.m(-2)) were randomly assigned to perform a RT program for 2 or 3 days per week (G2X = 13 vs. G3X = 14) for 12 weeks followed by 12 weeks of detraining period. One repetition maximum (1RM) tests were used as measures of muscular strength (three exercises, three attempts for each exercise, 3-5 min of rest between attempts, and 5 min of rest between exercises). Advanced oxidized protein products (AOPP) and total radical-trapping antioxidant parameter (TRAP) were used as oxidative stress indicators. Both groups increased muscular strength after 12 weeks of training (P < 0.05) in chest press (G2X = +11.9 % vs. G3X = +27.5 %, P < 0.05), knee extension (G2X = +18.4 % vs. G3X = +16.7 %, P > 0.05), and preacher curl (G2X = +37.6 % vs. G3X = +36.7 %, P > 0.05). On the other hand, 12 weeks of detraining were not sufficient to eliminate the major effects produced by RT on muscular strength, although a significant decrease (P < 0.05) has been observed for chest press (G3X = -9.1 % vs. G2X = -10.2 %, P > 0.05), knee extension (G2X = -14.9 % vs. G3X = -12.1 %, P > 0.05), and preacher curl (G2X = -20.5 % vs. G3X = -17.4 %, P > 0.05). Pre- to post-training, both groups showed significant (P < 0.05) increases in TRAP (G2X = +6.9 % vs. G3X = +15.1 %) with no statistical significant difference between the groups (P > 0.05), and the scores remained elevated compared to pre-training after 12 weeks of detraining. AOPP was not changed by RT or detraining (P > 0.05). The results suggest that a 12-week RT program with a frequency of 2 days per week may be sufficient to improve muscular strength and OS in older women and detraining for 12 weeks does not completely reverse the changes induced by RT.

Effect of resistance training and detraining on the oxidative stress in obese older women / Efeito do treinamento com pesos e do destreinamento sobre o estresse oxidativo em mulheres idosas obesas

Abstract The aim of this study was to investigate the effect of resistance training (RT) followed by a similar detraining period on the modulation of oxidative stress (OS) in obese older women. Fourteen obese women (age: 68.7 ± 4.8 years, body mass: 71.3 ± 14.8 kg, height: 156.3 ± 7.2 cm, body fat: 44.3 ± 4.4%) were submitted to 12 weeks of a RT program followed by a similar detraining period. Advanced oxidation protein products (AOPP) and total radical-trapping antioxidant potential (TRAP) were used as oxidative stress indicators. AOPP was not changed by RT or detraining (P = 0.31). Furthermore, TRAP was increased with RT (+ 15.1%; P < 0.001) and remained high even after 12 weeks of detraining (10.5%; P < 0.001). The results suggest that OS can be improved by RT and the 12-week detraining period does not seem to be enough to reverse adaptations induced by RT in obese older women.

Resumo O objetivo deste estudo foi investigar a efetividade do treinamento com pesos (TP), seguido por um período semelhante de destreinamento, sobre a modulação do estresse oxidativo (EO) em mulheres idosas obesas. Quatorze mulheres (idade: 68,7 ± 4,8 anos; massa corporal: 71,3 ± 14,8 kg; estatura: 156,3 ± 7,2 cm; gordura corporal: 44,3 ± 4,4%) obesas (gordura corporal relativa ≥ 30%) foram submetidas a 12 semanas de um programa de TP seguido por igual período de destreinamento. Os produtos de proteínas de oxidação avançada (AOPP) e a capacidade antioxidante total plasmática (TRAP) foram utilizados como indicadores de estresse oxidativo. A AOPP não foi alterada pelo TP ou pelo destreinamento (P = 0,31). Por outro lado, a TRAP foi aumentada com o TP (+15,1%; P < 0,001) e se manteve elevada mesmo após 12 semanas de destreinamento (+10,5%; P < 0,001). Os resultados sugerem que o EO pode ser melhorado pelo TP e o período de 12 semanas de destreinamento não parece ser suficiente para desfazer as adaptações induzidas pelo TP em mulheres idosas obesas.

Nível de ácido úrico como biomarcador diagnóstico e prognóstico de doenças cardiovasculares / Uric acid level as a diagnostic and prognostic biomarker of cardiovascular diseases

Diversos estudos propõem a relação entre hiperuricemia e doenças cardiovasculares, implicando em uma relação causal, aumento da morbimortalidade cardiovascular e melhoria da evolução clínica, por meio de farmacoterapia para redução de níveis de ácido úrico. A despeito destes achados, ainda incertos, o que a maioria das evidências sugere é que níveis de ácido úrico podem representar um biomarcador de diagnóstico e/ou prognóstico útil e barato. Portanto, a presente revisão de literatura apresenta as principais e mais recentes evidências sobre a relação de ácido úrico com doenças cardiovasculares, tais como aterosclerose, síndrome metabólica, doença arterial coronariana, insuficiência cardíaca, hipertensão, infarto agudo do miocárdio e mortalidade por doenças cardiovasculares. Os dados mais controversos dizem respeito à doença arterial coronariana, possivelmente por tratar-se de uma síndrome que contemple duas condições - angina instável e infarto agudo do miocárdio - tornando a análise pouco específica. A maioria dos estudos sugere que o ácido úrico, principalmente a hiperuricemia, seja um bom preditor diagnóstico (hipertensão e infarto agudo do miocárdio) e prognóstico (doença arterial coronariana e insuficiência cardíaca), no entanto poucos estudos avaliaram o desempenho do marcador em termos de curva ROC, sendo impossível emitir conclusões bem fundamentadas neste sentido. Considerando os resultados da maioria das evidências, a acessibilidade e o baixo custo da mensuração dos níveis de ácido úrico, é recomendável a integração da avaliação da hiperuricemia em um conjunto de análise de outros fatores de risco.

Several studies have suggested an association between hyperuricemia and cardiovascular diseases, resulting in a causal relationship, increased cardiovascular morbidity and improving clinical outcomes by means of pharmacotherapy for reducing uric acid levels. Though still uncertain, most studies suggest that levels of uric acid might be a useful and inexpensive biomarker for diagnosis and / or prognosis. Therefore, this literature review presents the most recent major evidence of uric acid related to cardiovascular diseases such as atherosclerosis, metabolic syndrome, coronary artery disease, heart failure, hypertension, myocardial infarction and mortality from cardiovascular disease. The most controversial data refer to coronary artery disease, possibly because it is a syndrome that includes two conditions - unstable angina and acute myocardial infarction - which makes the analysis low in specificity. Several articles have demonstrated that uric acid, especially hyperuricemia, is a good diagnosis predictor (hypertension and acute myocardial infarction) and prognosis (coronary artery disease and heart failure), however few studies have evaluated the performance of the marker in terms of ROC curve, making it impossible to deliver well-founded conclusions in this regard. Consideringthe results of most of the evidence, accessibility and low cost of measurements of uric acid levels, were commend to integrate both the evaluation of hyperuricemia and the analysis of other risk factors.