Cláudio Ricardo de Oliveira

The influences of positive end expiratory pressure (PEEP) associated with physiotherapy intervention in phase I cardiac rehabilitation

PURPOSE To evaluate the effects of positive end expiratory pressure and physiotherapy intervention during Phase I of cardiac rehabilitation on the behavior of pulmonary function and inspiratory muscle strength in postoperative cardiac surgery. METHODS A prospective randomized study, in which 24 patients were divided in 2 groups: a group that performed respiratory exercises with positive airway expiratory pressure associated with physiotherapy intervention (GEP, n = 8) and a group that received only the physiotherapy intervention (GPI, n = 16). Pulmonary function was evaluated by spirometry on the preoperative and on the fifth postoperative days; inspiratory muscle strength was measured by maximal inspiratory pressure on the same days. RESULTS Spirometric variables were significantly reduced from the preoperative to the fifth postoperative day for the GPI, while the GEP had a significant reduction only for vital capacity (P < .05). When the treatments were compared, smaller values were observed in the GPI for peak flow on the fifth postoperative day. Significant reductions of maximal inspiratory pressure from preoperative to the first postoperative day were found in both groups. However, the reduction in maximal inspiratory pressure from the preoperative to the fifth postoperative day was significant only in the GPI (P < .05). CONCLUSIONS These data suggest that cardiac surgery produces a reduction in inspiratory muscle strength, pulmonary volume, and flow. The association of positive expiratory pressure with physiotherapy intervention was more efficient in minimizing these changes, in comparison to the physiotherapy intervention alone. However, in both groups, the pulmonary volumes were not completely reestablished by the fifth postoperative day, and it was necessary to continue the treatment after hospital convalescence.

MMP(-2) expression in skeletal muscle after strength training.

The aim of this study was to assess the effects of resistance training on ladders (RTL) on MMP(-2) expression and blood lactate concentration [La-]. 30 male (3 months of age), albino rats were divided into 3 groups: sedentary control (SC, n=10), low resistance exercise training (Low-IntRT, n=10) and high-intensive exercise training (High-IntRT, n=10). Animals of High-IntRT were submitted to a progressively increasing overload in relation to body weight until exhaustion, while the Low-IntRT group performed the same exercise regimen with no external load. The program had a frequency of 3 times per week over 8 weeks. MMP(-2) expression of tibialis anterior muscle and [La-] were measured. While there was a significant increase of MMP(-2) (pro-form) in both groups, only High-IntRT significantly increased MMP(-2) in active-form (p<0.05). Both trained groups exhibited an increase in [La-] when compared to controls, however, the increase in [La-] was significantly higher in the High-IntRT compared to Low-IntRT (p<0.05). Strong correlation was found between MMP(-2) (active form) and [La-] in High-IntRT (r=0.91). RTL in using low and high-intensity exercise can serve as a model to demonstrate different responses of MMP(-2) expression in an animal model. It appears active form expression of MMP(-2) is modulated by exercise intensity.

Shuttle walking test in obese women: test-retest reliability and concurrent validity with peak oxygen uptake

The aim of this study was to evaluate the test–retest reliability, concurrent validity and agreement with peak oxygen uptake (VO2) obtained during cardiopulmonary exercise testing (CPX) on a treadmill for the incremental shuttle walking test (ISWT) in obese women.

Prediction of Cardiorespiratory Fitness by the Six-Minute Step Test and Its Association with Muscle Strength and Power in Sedentary Obese and Lean Young Women: A Cross-Sectional Study

Impaired cardiorespiratory fitness (CRF) is a hallmark characteristic in obese and lean sedentary young women. Peak oxygen consumption (VO2peak) prediction from the six-minute step test (6MST) has not been established for sedentary females. It is recognized that lower-limb muscle strength and power play a key role during functional activities. The aim of this study was to investigate cardiorespiratory responses during the 6MST and CPX and to develop a predictive equation to estimate VO2peak in both lean and obese subjects. Additionally we aim to investigate how muscle function impacts functional performance. Lean (LN = 13) and obese (OB = 18) women, aged 20–45, underwent a CPX, two 6MSTs, and isokinetic and isometric knee extensor strength and power evaluations. Regression analysis assessed the ability to predict VO2peak from the 6MST, age and body mass index (BMI). CPX and 6MST main outcomes were compared between LN and OB and correlated with strength and power variables. CRF, functional capacity, and muscle strength and power were lower in the OB compared to LN (<0.05). During the 6MST, LN and OB reached ~90% of predicted maximal heart rate and ~80% of the VO2peak obtained during CPX. BMI, age and number of step cycles (NSC) explained 83% of the total variance in VO2peak. Moderate to strong correlations between VO2peak at CPX and VO2peak at 6MST (r = 0.86), VO2peak at CPX and NSC (r = 0.80), as well as between VO2peak, NSC and muscle strength and power variables were found (p<0.05). These findings indicate the 6MST, BMI and age accurately predict VO2peak in both lean and obese young sedentary women. Muscle strength and power were related to measures of aerobic and functional performance.

Lactate and heart rate variability threshold during resistance exercise in the young and elderly

This purpose of this study was to: 1) determine the intensity corresponding to anaerobic threshold (AT) during a discontinuous resistance exercise protocol in healthy young and elderly subjects by analyzing heart rate variability (HRV) and blood lactate (BL) and 2) investigate the effect of aging on these variables. A total of 28 individuals, 14 young and 14 elderly healthy men underwent one-repetition maximum (1RM) testing to determine maximum load on the leg press. Discontinuous resistance exercise testing was initiated at 10% of the 1RM with subsequent increases of 10%. The load corresponding to AT was approximately 30% 1RM in both groups. The determination of AT by HRV was associated with BL responses (p<0.01). While HRV indexes decreased with increasing of loads in both groups, the elderly had lower values at loads below AT (p<0.05). Additionally, BL increased sharply after the load corresponding to AT in both groups, although elderly subjects showed the lowest values (p<0.05). In conclusion, HRV is an effective tool for determining AT, which was approximately 30% 1RM under the testing procedures included in the present study. Furthermore, there was a marked change in autonomic function, with gradual vagal withdrawal followed by sympathetic activation. These responses were lower in elderly subjects.

Identification of anaerobic threshold by analysis of heart rate variability during discontinuous dynamic and resistance exercise protocols in healthy older men

The purposes of this study were to determine anaerobic threshold (AT) during discontinuous dynamic and resistive exercise protocols by analysing of heart rate variability (HRV) and blood lactate (BL) in healthy elderly subjects and compare the cardiovascular, metabolic and autonomic variables obtained from these two forms of exercise. Fourteen elderly (70 ± 4 years) apparently healthy males underwent the following tests: (i) incremental ramp test on cycle ergometer, (ii) one repetition maximum (1RM) leg press at 45°, (iii) a discontinuous exercise test on a cycle ergometer (DET‐C) protocol and (iv) a resistance exercise leg press (DET‐L) protocol. Heart rate, blood pressure and BL were obtained during each increment of exercise intensity. No significant differences (P>0·05) were found between methods of AT determination (BL and HRV) nor the relative intensity corresponding to AT (30% of maximum intensity) between the types of exercise (DET‐C and DET‐L). Furthermore, no significant differences (P>0·05) were found between the DET‐C and DET‐L in relation to HRV, however, the DET‐L provided higher values of systolic blood pressure and BL (P<0·05) from the intensity corresponding to AT. We conclude that HRV was effective in determination of AT, and the parasympathetic modulation responses obtained during dynamic and resistive exercise protocols were similar when compared at the same relative intensity. However, DET‐L resulted in higher values of blood pressure and BL at workloads beyond AT.

Metabolic and cardiac autonomic effects of high-intensity resistance training protocol in Wistar rats.

Deus, AP, Oliveira, CR, Simões, RP, Baldissera, V, Silva, CA, Rossi, BRO, Sousa, HCD, Parizotto, NA, Arena, R, and Borghi-Silva, A. Metabolic and cardiac autonomic effects of high-intensity resistance training protocol in Wistar rats. J Strength Cond Res 26(3): 618–624, 2012—The aim of this study was to assess the effects of metabolic and autonomic nervous control on high-intensity resistance training (HRT) as determined by pancreatic glucose sensitivity (GS), insulin sensitivity (IS), blood lactate ([La]), and heart rate variability (HRV) in rats. Thirty male, albino Wistar rats (292 ± 20 g) were divided into 3 groups: sedentary control (SC), low-resistance training (LRT), and HRT. The animals in the HRT group were submitted to a high-resistance protocol with a progressively increasing load relative to body weight until exhaustion, whereas the LRT group performed the same exercise regimen with no load progression. The program was conducted 3 times per week for 8 weeks. The [La], parameters related to the functionality of pancreatic tissue, and HRV were measured. There was a significant increase in peak [La] only in the HRT group, but there was a reduction in [La] when corrected to the maximal load in both trained groups (LRT and HRT, p < 0.05). Both trained groups exhibited an increase in IS; however, compared with SC and LRT, HRT demonstrated a significantly higher GS posttraining (p < 0.05). With respect to HRV, the low-frequency (LF) band, in milliseconds squared, reduced in both trained groups, but the high-frequency band, in milliseconds squared and nu, increased, and the LF in nu, decreased only in the HRT group (p < 0.05). The HRT protocol produced significant and beneficial metabolic and cardiac autonomic adaptations. These results provide evidence for the positive benefits of HRT in counteracting metabolic and cardiovascular dysfunction.

Poor glycemic control impacts linear and non-linear dynamics of heart rate in DM type 2

INTRODUCAO: E de conhecimento geral que o diabetes mellitus tipo 2 (DM2) produz neuropatia autonomica cardiovascular (NAC), que pode afetar a modulacao autonomica cardiaca. Entretanto, nao e claro se a falta de controle glicemico em diabeticos tipo 2 sem NAC, poderia impactar negativamente na modulacao autonomica cardiaca. Objetivo: Avaliar a relacao entre controle glicemico e modulacao autonomica cardiaca em individuos com DM2 sem neuropatia autonomica cardiovascular. Estudo descritivo, prospectivo e transversal. METODOS: Quarenta e nove pacientes com DM2 (51±7 anos) foram divididos em dois grupos de acordo com a hemoglobina glicosilada (HbA1c): G1: ≤ 7% e G2: >7,0%. A frequencia cardiaca de repouso (FC) e intervalo RR (iRR) foram obtidos e calculados por metodos lineares (media iRR; media FC; rMSSD; STD RR; LF; HF; LF/HF, TINN e RR Tri) e nao lineares (SD1; SD2; DFα1; DFα2, Entropia de Shannon; ApEn; SampEn e CD) de variabilidade de frequencia cardiaca. Insulina, HOMA-IR, glicemia de jejum e HbA1c foram obtidas por analises sanguineas. RESULTADOS: G2 (HbA1c ≤ 7%) mostrou valores menores para media de iRR; STD RR; RR Tri, TINN, SD2, CD e maiores para media de FR quando comparado com G1 (HbA1c > 7%). Adicionalmente, HbA1c correlacionou-se negativamente com media iRR (r=0,28, p=0,044); STD RR (r=0,33, p=0,017); RR Tri (r=-0,35, p=0,013), SD2 (r=-0,39, p=0,004) e positivamente com media FC (r=0,28, p=0,045). Finalmente, a glicemia de jejum correlacionou-se negativamente com STD RR (r=-0,36, p=0,010); RR Tri (r=-0,36, p=0,010); TINN (r=-0,33, p=0,019) e SD2 (r=-0,42, p=0,002). CONCLUSAO: Conclui que o controle glicemico deficiente relaciona-se com indices de modulacao autonomica cardiaca em individuos com DM2, ainda que nao apresentem neuropatia autonomica cardiovascular.INTRODUCCION: Es de conocimiento general que la diabetes mellitus tipo 2 (DM2) produce neuropatia autonomica cardiovascular (NAC), que puede afectar la modulacion autonomica cardiaca. Entretanto, no es claro si la falta de control glucemico en diabeticos tipo 2 sin NAC, podria impactar negativamente en la modulacion autonomica cardiaca. Objetivo: Evaluar la relacion entre control glucemico y modulacion autonomica cardiaca en individuos con DM2 sin neuropatia autonomica cardiovascular. Estudio descriptivo, prospectivo y transversal. METODOS: Cuarenta y nueve pacientes con DM2 (51±7 anos) fueron divididos en dos grupos de acuerdo con la hemoglobina glucosilada (HbA1c): G1: ≤ 7% y G2: >7,0%. La frecuencia cardiaca de reposo (FC) e intervalo RR (iRR) fueron obtenidos y calculados por metodos lineales (promedio iRR; promedio FC; rMSSD; STD RR; LF; HF; LF/HF, TINN y RR Tri) y no lineales (SD1; SD2; DFα1; DFα2, Entropia de Shannon; ApEn; SampEn y CD) de variabilidad de frecuencia cardiaca. Fueron obtenidas insulina, HOMA-IR, glucemia en ayunas y HbA1c a traves de analisis sanguineos. RESULTADOS: G2 (HbA1c ≤ 7%) mostro valores menores para el promedio de iRR; STD RR; RR Tri, TINN, SD2, CD y mayores para el promedio de FR al ser comparado con G1 (HbA1c > 7%). Adicionalmente, HbA1c se correlaciono negativamente con el promedio iRR (r=0,28, p=0,044); STD RR (r=0,33, p=0,017); RR Tri (r=-0,35, p=0,013), SD2 (r=-0,39, p=0,004) y positivamente con el promedio FC (r=0,28, p=0,045). Finalmente, la glucemia en ayunas se correlaciono negativamente con STD RR (r=-0,36, p=0,010); RR Tri (r=-0,36, p=0,010); TINN (r=-0,33, p=0,019) e SD2 (r=-0,42, p=0,002). CONCLUSION: Concluimos que el control glucemico deficiente se relaciona con indices de modulacion autonomica cardiaca en individuos con DM2, aunque no presenten neuropatia autonomica cardiovascular.

Effects of Blocking αvβ3 integrin by a recombinant RGD disintegrin on remodeling of wound healing after induction of incisional hernia in rats

PURPOSE To investigate the changes induced by DisBa-01 on repair of wound healing after induced incisional hernia (IH) in rats. METHODS Thirty two male albino rats were submitted to IH and divided into four experimental groups: G1, placebo control; G2, DisBa-01-treated; G3, anti-αvβ3 antibodies-treated and G4, anti-α2 antibodies-treated. Histological, biochemical and extracellular matrix remodeling analysis of abdominal wall were evaluated. RESULTS After 14 days, 100% of the G2 did not present hernia, and the hernia ring was closed by a thin membrane. In contrast, all groups maintained incisional hernia. DisBa-01 also increased the number macrophages and fibroblasts and induced the formation of new vessels. Additionally, MMP-2 was strongly activated only in G2 (p<0.05). Anti- αvβ3-integrin antibodies produced similar results than DisBa-01 but not anti-α2 integrin blocking antibodies. CONCLUSION DisBa-01 has an important role in the control of wound healing and the blocking of this integrin may be an interesting therapeutically strategy in incisional hernia.

Effects of inspiratory muscle training in professional women football players: a randomized sham-controlled trial

ABSTRACT This study was conducted to determine the effects of inspiratory muscle training (IMT) on respiratory and peripheral muscles oxygenation during a maximal exercise tolerance test and on repeated-sprint ability (RSA) performance in professional women football players. Eighteen athletes were randomly assigned to one of the following groups: SHAM (n = 8) or IMT (n = 10). After a maximal incremental exercise test, all participants performed (on a different day) a time-to-exhaustion (Tlim) test. Peripheral and respiratory muscles oxygenation by near-infrared spectroscopy, breath-by-breath ventilatory and metabolic variables, and blood lactate concentration were measured. The RSA test was performed on a grass field. After a 6 week intervention, all athletes were reevaluated. Both groups showed increases in inspiratory muscles strength, exercise tolerance and RSA performance, however only the IMT group presented lower deoxyhemoglobin and total hemoglobin blood concentrations on intercostal muscles concomitantly to an increased oxyhemoglobin and total hemoglobin blood concentrations on vastus lateralis muscle during Tlim. In conclusion, these results may indicate the potential role of IMT to attenuate inspiratory muscles metaboreflex and consequently improve oxygen and blood supply to limb muscles during high-intensity exercise, with a potential impact on inspiratory muscle strength, exercise tolerance and sprints performance in professional women football players.