Laila Cândida de Jesus Lima

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.

Hypotensive effects of exercise performed around anaerobic threshold in type 2 diabetic patients

AIM To verify the occurrence of post-exercise hypotension (PEH) in type 2 diabetics (DM(2)) and the effects of exercise intensity on post-exercise blood pressure (BP). METHODS Eleven men and women with DM(2) (58.5+/-10.2 years; 160+/-0.1cm; 80.6+/-13.5kg; 31.2+/-3.8kg/m(2), 19+/-3.2mLkgmin(-1) of VO(2max), 155.0+/-39.2mgdL(-1) of fasting blood glucose and 126+/-10/75+/-7mmHg of resting BP) performed an incremental test (IT) for cardiovascular evaluation and anaerobic threshold (AT) determination. Then, participants randomly underwent 2 exercise sessions (90% and 110% AT) and a control session (CON). In all sessions, BP was measured at resting, during 20min of exercise/control and at each 15min through 120min of post-exercise recovery (R15-R120). RESULTS The mean results of systolic BP (SBP)/diastolic BP (DBP) over the 120min of recovery were 125+/-16/76+/-7mmHg, 122+/-13/75+/-6mmHg and 129+/-16/78+/-7mmHg, respectively for 90%, 110% and CON. Significant reductions of SBP occurred after 90% (R15-R45) and 110% (R15-R90), while only after 110% there were reductions of DBP (R15, R45) and MAP (R15, R45, R75, R90, R105). CONCLUSIONS Both exercise intensities evoked reductions in SBP while DBP and MAP were reduced only after 110%. Despite the higher intensity exercise to be more effective in promoting BP reductions, we suggest caution while prescribing exercise for DM(2).

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.

Effect of type 2 diabetes on plasma kallikrein activity after physical exercise and its relationship to post-exercise hypotension

AIM The present study was undertaken to determine the effects of type 2 diabetes (T2D) on plasma kallikrein activity (PKA) and postexercise hypotension (PEH). METHODS Ten T2D patients (age: 53.6±1.3 years; body mass index: 30.6±1.0kg/m(2); resting blood glucose: 157.8±40.2mgdL(-1)) and 10 non-diabetic (ND) volunteers (age: 47.5±1.0 years; body mass index: 28.3±0.9kg/m(2); resting blood glucose: 91.2±10.5mgdL(-1)) underwent two experimental sessions, consisting of 20min of rest plus 20min of exercise (EXE) at an intensity corresponding to 90% of their lactate threshold (90LT) and a non-exercise control (CON) session. Blood pressure (BP; Microlife BP 3AC1-1 monitor) and PKA were measured during rest and every 15min for 135min of the postexercise recovery period (RP). RESULTS During the RP, the ND individuals presented with PEH at 30, 45 and 120min (P<0.05) while, in the T2D patients, PEH was not observed at any time. PKA increased at 15min postexercise in the ND (P<0.05), but not in the T2D patients. CONCLUSION T2D individuals have a lower PKA response to exercise, which probably suppresses its hypotensive effect, thus reinforcing the possible role of PKA on PEH.

Assessment of aerobic capacity during swimming exercise in ob/ob mice

Obesity is a highly prevalent condition associated with several diseases. Physical exercise has been considered as a non‐pharmacological tool in the treatment of obesity. However, several aspects underlying exercise evaluation and prescription in obesity and associated pathologies are still under investigation. Although many research involving exercise have been performed in animal models, there is a lack of protocols for aerobic capacity assessment in obese animals, such as the ob/ob mice. This study aimed the following: (i) to verify the possibility of determining the lactate threshold (LT) on swimming exercise in ob/ob mice and in non‐obese heterozygote mice (ob/OB), through visual inspection (vLT) and polynomial adjustment (pLT); and (ii) to verify if the LT determined through these protocols corresponds to the maximal lactate steady state (MLSS). Eight ob/ob and ten ob/OB mice performed an incremental exercise test to determine vLT and pLT as well as constant‐load exercise bouts to determine MLSS. There were no within‐group differences between vLT, pLT and MLSS [ob/ob: ~5.3% body weight (BW); ob/OB: ~3·6%BW] with a high agreement among protocols. In conclusion, the identification of the LT and MLSS intensities was possible for both groups. These data suggest that the proposed protocols may be used in new research on the effects of different exercise intensities on some aspects of obesity. Copyright

Respostas cardiovasculares pós-exercício de natação

INTRODUCAO: A crescente procura da natacao como um tratamento nao-farmacologico da hipertensao arterial tem aumentado. Objetivo: Analisar as respostas da pressao arterial (PA) apos o exercicio de natacao e durante a rotina diaria de trabalho de individuos pre-hipertensos. METODOS: Oito individuos pre-hipertensos (128,2 ± 7,8 / 77,8 ± 6,0mmHg; 41,8 ± 3,2 anos; 84,7 ± 17,9kg; 180,4 ± 4,8cm; 27,3 ± 5,8kg.m2(-1)) foram submetidos a duas sessoes, sendo uma de natacao (SN) e a outra de controle (SC). A PA foi medida no repouso pre-exercicio e durante 12 horas de recuperacao pos-exercicio. Na SN, os pacientes nadaram por 45min em uma intensidade moderada a alta (PSE 14,5 ± 1,6), e, durante a SC, os sujeitos permaneceram em repouso na posicao sentada pelo mesmo periodo de tempo. RESULTADOS: ANOVA para medidas repetidas evidenciou diminuicao significativa (p < 0,05) na PAS por duas horas apos a SN em relacao ao repouso, e uma diferenca significativa entre os deltas do PAS (Δ - PAS variacao na recuperacao pos-exercicio em relacao ao repouso pre-exercicio) foi observada entre as sessoes na primeira e segunda horas apos a recuperacao, respectivamente (ΔSS = -10,4 e -9,3 vs. ΔCS = 0,8 e 4,4mmHg, p < 0,05). Nγo houve diferencas significativas da PAD, intra e entre as sessoes. CONCLUSAO: O exercicio de natacao em intensidade moderada a alta foi eficaz para promover reducao da PA pos-exercicio em individuos hipertensos durante a sua rotina de trabalho.