Gisela Arsa

Type 2 Diabetes Elicits Lower Nitric Oxide, Bradykinin Concentration and Kallikrein Activity Together with Higher DesArg9-BK and Reduced Post-Exercise Hypotension Compared to Non-Diabetic Condition

This study compared the plasma kallikrein activity (PKA), bradykinin concentration (BK), DesArg9-BK production, nitric oxide release (NO) and blood pressure (BP) response after moderate-intensity aerobic exercise performed by individuals with and without type 2 diabetes. Ten subjects with type 2 diabetes (T2D) and 10 without type 2 diabetes (ND) underwent three sessions: 1) maximal incremental test on cycle ergometer to determine lactate threshold (LT); 2) 20-min of constant-load exercise on cycle ergometer, at 90% LT and; 3) control session. BP and oxygen uptake were measured at rest and at 15, 30 and 45 min post-exercise. Venous blood samples were collected at 15 and 45 minutes of the recovery period for further analysis of PKA, BK and DesArg9-BK. Nitrite plus nitrate (NOx) was analyzed at 15 minutes post exercise. The ND group presented post-exercise hypotension (PEH) of systolic blood pressure and mean arterial pressure on the 90% LT session but T2D group did not. Plasma NOx increased ~24.4% for ND and ~13.8% for T2D group 15min after the exercise session. Additionally, only ND individuals showed increases in PKA and BK in response to exercise and only T2D group showed increased DesArg9-BK production. It was concluded that T2D individuals presented lower PKA, BK and NOx release as well as higher DesArg9-BK production and reduced PEH in relation to ND participants after a single exercise session.

Effects of treadmill running and resistance exercises on lowering blood pressure during the daily work of hypertensive subjects.

Mota, MR, Pardono, E, Lima, LCJ, Arsa, G, Bottaro, M, Campbell, CSG, and Simões, HG. Effects of treadmill running and resistance exercises on lowering blood pressure during the daily work of hypertensive subjects. J Strength Cond Res 23(8): 2331-2338, 2009-The purposes of this study were to compare the hypotensive effects of treadmill running (TR) and resistance exercise (RE) performed by hypertensive subjects and to verify if the hypotensive effects of these exercises are maintained during a regular white-collar workday. Fifteen white-collar workers (42.9 ± 1.6 years), treated with antihypertensive medication, accomplished three different sessions: 20 minutes of TR (∼70-80% of heart rate reserve), 20 minutes of circuit training RE (20 repetitions at 40% of 1 repetition maximum), and a control session without exercise (CON). The systolic blood pressure (BP), diastolic BP, heart rate, and blood lactate were measured at resting (Rest) and after sessions at 15th (R15), 30th (R30), 45th (R45), and 60th (R60) min, as well as after lunch (AL), four (R4h) and seven (R7h) hours of recovery at the participants workplace. In relation to rest, a higher decrease of systolic BP after TR (−11.1 ± 7.6 mm Hg) and RE (−12.6 ± 7.3 mm Hg) was observed respectively at the R30 and R45. For diastolic BP, the highest decreases after TR (−4.0 ± 6.4 mm Hg) and RE (−9.0 ± 7.0 mm Hg) were observed respectively at the R45 and R30. The systolic BP and mean BP after TR and RE differed significantly from CON session (p < 0.05), and lower post-exercise values could be observed over the workday. In conclusion, both 20 minutes of TR and RE resulted in postexercise hypotension, and were able to reduce BP throughout 7 hours after exercise, even throughout the subjects regular occupational activities. Also, the RE promoted higher cardiac protection and can be a useful model of physical exercise prescription for hypertension individuals.

Methods to identify the lactate and glucose thresholds during resistance exercise for individuals with type 2 diabetes.

Moreira, SR, Arsa, G, Oliveira, HB, Lima, LCJ, Campbell, CSG, Simões, HG. Methods to identify the lactate and glucose thresholds during resistance exercise for individuals with type 2 diabetes. J Strength Cond Res 22: 1108-1115, 2008-The purpose of this study was to compare different methods to identify the lactate threshold (LT) and glucose threshold (GT) on resistance exercise for individuals with type 2 diabetes. Nine men with type 2 diabetes (47.2 ± 12.4 years, 87.6 ± 20.0 kg, 174.9 ± 5.9 cm, and 22.4 ± 7.2% body fat) performed incremental tests (ITs) on the leg press (LP) and bench press (BP) at relative intensities of 10, 20, 25, 30, 35, 40, 50, 60, 70, 80, and 90% of one-repetition maximum (1RM) at each 1-minute stage. During the 2-minute interval between stages, 25 μl of capillary blood were collected from the earlobe for blood lactate [Lac] and blood glucose [Gluc] analysis (YSI 2700S). The LT in the LP and BP was identified at IT by the inflexion in [Lac] response as well as by an equation originated from a polynomial adjustment (LTp) of the [Lac]/% 1RM ratio responses. The lowest [Gluc] during the IT identified the GT. The analysis of variance did not show differences among the 1RM at the thresholds identified by different methods in the LP (LTLP = 31.0% ± 5.3% 1RM; GTLP = 32.1% ± 6.1% 1RM; LTpLP = 36.7% ± 5.6% 1RM; p > 0.05) and BP (LTBP = 29.9% ± 8.5% 1RM; GTBP = 32.1% ± 8.5% 1RM; LTpBP = 31.8% ± 6.7% 1RM; p > 0.05). It was concluded that it was possible to identify the LT and GT in resistance exercise by different methods for individuals with type 2 diabetes with no differences between them. The intensities (kg) corresponding to these thresholds were between 46% and 60% of the body weight on the LP and between 18% and 26% of the body weight on the BP, in which the exercise prescription would be done to this intensity in 3 sets of 20 to 30 repetitions each and 1 minute of rest while alternating the muscle groups for blood glucose control for individuals with characteristics similar to the participants.

Exercise lowers blood pressure in university professors during subsequent teaching and sleeping hours

Background University professors are subjected to psychological stress that contributes to blood pressure (BP) reactivity and development of hypertension. The purpose of this study was to investigate the effects of exercise on BP in university professors during teaching and sleeping hours. Methods Twelve normotensive professors (42.2 ± 10.8 years, 74.2 ± 11.2 kg, 172.8 ± 10.4 cm, 20.1% ± 6.7% body fat) randomly underwent control (CONT) and exercise (EX30) sessions before initiating their daily activities. EX30 consisted of 30 minutes of cycling at 80%–85% of heart rate reserve. Ambulatory BP was monitored for 24 hours following both sessions. Results BP increased in comparison with pre-session resting values during teaching after CONT (P < 0.05) but not after EX30. Systolic, diastolic, and mean arterial BP showed a more pronounced nocturnal dip following EX30 (approximately –14.7, –12.7, and –9.6 mmHg, respectively) when compared with CONT (approximately –6, –5 and –3 mmHg). Conclusion Exercise induced a BP reduction in university professors, with the main effects being observed during subsequent teaching and sleeping hours.

Water aerobics is followed by short-time and immediate systolic blood pressure reduction in overweight and obese hypertensive women

One exercise training session such as walking, running, and resistance can lead to a decrease in blood pressure in normotensive and hypertensive individuals, but few studies have investigated the effects of exercise training in an aquatic environment for overweight and obese hypertensive individuals. We aimed to assess the acute effects of a water aerobics session on blood pressure changes in pharmacologically treated overweight and obese hypertensive women. A randomized crossover study was carried out with 18 hypertensive women, 10 of them were overweight (54.4xa0±xa07.9xa0years; body mass index: 27.8xa0±xa01.7xa0kg/m(2)) and eight obese (56.4xa0±xa06.6xa0years; body mass index: 33.0xa0±xa02.0xa0kg/m(2)). The water aerobics exercise session consisted of a 45-minute training at the intensity of 70%-75% of maximum heart rate adjusted for the aquatic environment. The control group did not enter the pool and did not perform any exercise. We measured systolic blood pressure (SBP) and diastolic blood pressure (DBP) before, immediately after, and every 10xa0minutes up to 30xa0minutes after the aerobic exercise or control session. Overall (nxa0=xa018), DBP did not change after the water aerobic exercise and control session, and SBP decreased at 10 and 20xa0minutes postexercise compared to the control session. Among overweight women, SBP decreased at 10 and 20xa0minutes postexercise. In contrast, among obese women, SBP decreased only at 10xa0minutes postexercise. SBP variation was -2.68xa0mm Hg in overweight and -1.24xa0mm Hg in obese women. In conclusion, the water aerobics session leads to a reduction in SBP, but not in DBP, during 10 and 20xa0minutes postexercise recovery. Thus, it may be safely prescribed to overweight and obese women.

Different land-based exercise training programs to improve bone health in postmenopausal women

Summary Bone mineral density reduction is a health problem in postmenopausal women because it leads to osteoporosis and high risk of falling, and bone fracture. Bone fractures induce functional dis-ability, poor quality of life, and reduced lifespan. Thus, therapies that reduce bone loss are highly necessary. In this study, we summarized findings from the literature regarding several useful land-based (as opposed to aquatic) exercise training programs for bone density maintenance in post-menopausal women. Trials published up to January 2013 in Cochrane Library, PubMed, and Medline databases (n=1966) were evaluated. The search included studies assessing ET effects on BMD in postmenopausal women. In the current literature, 4 types of exercise training programs (resistance, endurance, whole-body vibration, and multi-component training) have shown benefit in multiple bone sites. However, sev -eral studies provide a more positive clinical perspective for multi-component training. We show evidence that several land training programs may benefit bone health, in which multi-component training is most recommended. This is based on findings that multi-component train -ing induces lower fall frequency and risk for osteoporosis.

Blood pressure and cardiac autonomic modulation at rest, during exercise and recovery time in the young overweight

This study aimed to assess the blood pressure (BP), cardiac autonomic modulation at rest, in physical exercise and in the recovery in untrained eutrophic (E) and overweight (O) youth. The body mass index (BMI), waist circumference (WC), systolic BP-SBP (E: 109.80 ± 10.05; O: 121.85 ± 6.98 mmHg) and diastolic BP - DBP (E: 65.90 ± 7.28; O: 73.14 ± 12.22 mmHg) were higher in overweight and the heart rate recovery (%HRR) was lower as compared with E volunteers. The BMI was associated with SBP (r= 0.54), DBP (r= 0.65), load on the heart rate variability threshold - HRVT (r= -0.46), %HRR 2 (r= -0.48) and %HRR 5 (r= -0.48), and WC was associated with SBP (r= 0.54), DBP (r= 0.64) and HRR 2 (r= -0.49). The %HRR was associated to SBP, DBP and HRVT. In summary, the anthropometric variables, BP and cardiac autonomic modulation in the recovery are altered in overweight youth.

Does Stroke Volume Increase During an Incremental Exercise? A Systematic Review

Introduction: Cardiac output increases during incremental-load exercise to meet metabolic skeletal muscle demand. This response requires a fast adjustment in heart rate and stroke volume. The heart rate is well known to increase linearly with exercise load; however, data for stroke volume during incremental-load exercise are unclear. Our objectives were to (a) review studies that have investigated stroke volume on incremental load exercise and (b) summarize the findings for stroke volume, primarily at maximal-exercise load. Methods: A comprehensive review of the Cochrane Library’s, Embase, Medline, SportDiscus, PubMed, and Web of Sci-ence databases was carried out for the years 1985 to the present. The search was performed between February and June 2014 to find studies evaluating changes in stroke volume during incremental-load exercise. Controlled and uncontrolled trials were evaluated for a quality score. Results: The stroke volume data in maximal-exercise load are inconsistent. There is evidence to hypothesis that stroke volume increases during maximal-exercise load, but other lines of evidence indicate that stroke volume reaches a plateau under these circumstances, or even decreases. Conclusion: The stroke volume are unclear, include contradictory evidence. Additional studies with standardized reporting for subjects (e.g., age, gender, physical fitness, and body position), exercise test protocols, and left ventricular function are required to clarify the characteristics of stroke volume during incremental maximal-exercise load.

Heart rate inflection point estimates the anaerobic threshold in overweight and obese young adults

Anaerobic threshold (AT) can be determined by heart rate variability (HRVT) and by heart rate inflection point (HRIP), which is associated with lactate and ventilatory thresholds. Thus, this study aimed to compare the HRVT and HRIP in normal weight (NW: 22.18xa0±xa01.90xa0kgxa0m−2), overweight (Ov: 27.12xa0±xa01.39), and obese (O: 32.85xa0±xa02.40) young people (21.62xa0±xa02.09xa0years old; n: 61). AT was determined by: (1) HRVT using two criteria: HRVT1: first workload with SD1 index <3xa0ms; HRVT2: first workload with a difference <1xa0ms in the SD1 index between two consecutive stages; and (2) HRIP: identified on the maximum distance between a polynomial adjustment and the linear values of HR. The HRIP was identified at similar workloads (NW: 89.35xa0±xa032.45; Ov: 83.57xa0±xa024.45; O: 105.71xa0±xa029.80xa0W) and heart rate (NW: 130.78xa0±xa015.32; Ov: 126.29xa0±xa011.71; 136.24xa0±xa013.43xa0bpm). No significant differences (pxa0>xa00.05) between criteria, methods or groups, and a significant (pxa0<xa00.05) correlation (r 0.28–0.63) were observed for all variables between HRVT1 and HVRT2; for workload between HRVT1 with HRIP (r 0.28); and to rate perceived exertion between HRVT1 (r 0.28) and HVRT2 (r 0.48) with HRIP, with a good agreement for HR between all the methods used for AT identification. In summary, obesity does not seem to interfere on the identification of AT, and HRIP can be used as a reliable method for untrained young people with a wide BMI range.

LIMIAR ANAERÓBIO A PARTIR DA PSE EM EXERCÍCIO RESISTIDO POR MODELOS MATEMÁTICOS

Introduccion: El umbral anaerobico se identifica comunmente en los ejercicios ciclicos, sin embargo, tambien se puede determinar en el ejercicio de resistencia (ER) por diferentes metodos, y por lo tanto, se puede estimar la carga de trabajo relacionada con el estres metabolico. No obstante, su identificacion por otros metodos como el modelo matematico de DMax y sobre todo mediante variables mas accesibles, como el esfuerzo percibido (EP), todavia no se ha analizado. Objetivo: Comparar el umbral de lactato (UL) identificado por el metodo de inspeccion visual (ULIV) con el metodo DMax aplicado a las respuestas de lactato (ULDMax) y EP (EP12/13 y EPDMax) durante los ejercicios de resistencia incremental. Metodos: Diez practicantes de ER (24,8 ± 3,0 anos) fueron sometidos a la prueba de una repeticion maxima (1-RM) y una prueba incremental en la prensa de piernas, obteniendo el EP y el lactato en cada etapa. Resultados: Fue posible identificar el umbral anaerobico por todos los metodos, entre el 30% y el 40% de 1-RM. Las cargas absolutas, las concentraciones de lactato en sangre y EP no fueron diferentes entre los metodos utilizados y mostraron buena concordancia entre si. Conclusion: Es posible identificar el umbral anaerobico tanto por inspeccion visual como por el modelo matematico de DMax de lactato y el EP, ampliando las posibilidades de determinar el umbral anaerobico en el ejercicio de resistencia por metodos de bajo costo y no invasivos.