Spectral analyses of systolic blood pressure and heart rate variability and their association with cognitive performance in elderly hypertensive subjects.

Systolic hypertension is associated with cognitive decline in the elderly. Altered blood pressure (BP) variability is a possible mechanism of reduced cognitive performance in elderly hypertensives. We hypothesized that altered beat-to-beat systolic BP variability is associated with reduced global cognitive performance in elderly hypertensive subjects. In exploratory analyses, we also studied the correlation between diverse discrete cognitive domains and indices of systolic BP and heart rate variability. Disproving our initial hypothesis, we have shown that hypertension and low education, but not indices of systolic BP and heart rate variability, were independent predictors of lower global cognitive performance. However, exploratory analyses showed that the systolic BP variability in semi-upright position was an independent predictor of matrix reasoning (B = 0.08 ± .03, P-value = 0.005), whereas heart rate variability in semi-upright position was an independent predictor of the executive function score (B = -6.36 ± 2.55, P-value = 0.02). We conclude that myogenic vascular and sympathetic modulation of systolic BP do not contribute to reduced global cognitive performance in treated hypertensive subjects. Nevertheless, our results suggest that both systolic BP and heart rate variability might be associated with modulation of frontal lobe cognitive domains, such as executive function and matrix reasoning.

Work volume in strength training is not affected by rest interval strategy.

AIM: Between-set rest intervals (RI) may be determined using exercise-recovery-ratio (ERR) or fixed periods. The study investigated the influence of different ERR and fixed RI on the training volume in sessions aiming for hypertrophy with upper-body exercises recruiting different muscle mass (bench press-BP and triceps extension-TE). METHODS: Sixteen men (25±2 years, 78±6 kg, 178±5 cm) with previous experience in resistance training performed 5 sets of maximum repetitions in each exercise with five RI protocols (RR1:3 [I3]; ERR1:5 [I5]; ERR1:7 [I7]; increasing ERR [IP] (1:3-1:5-1:7-1:9); 2-min fixed [2F]) in a counterbalanced design. The number of repetitions and work volume (load x repetitions) in each set and along the sessions (load x repetitions x sets) were compared across the RI protocols. RESULTS: The maximum repetitions decreased along with the sets in both exercises, but TE had lower percent decrease compared to BP, due to a longer time to perform the sets and therefore longer absolute rest time (P<0.05). The I3 exhibited the lowest repetitions sustainability (P<0.05). The training volume in I7, IP and 2F was always higher than I3 and I5 (P>0.05). However the absolute RI in 2F (~2 min) was shorter than in I7 and IP (~3 min), which reduced the total duration of the training session. CONCLUSION: Determining between-set RI based on ERR instead of using fixed intervals does not enable more work to be done in multiple-set/high intensity resistance training sessions.

Effects of Growth Hormone Administration on Muscle Strength in Men over 50 Years Old.

Growth hormone (GH) use has been speculated to improve physical capacity in subjects without GH deficiency (GHD) through stimulation of collagen synthesis in the tendon and skeletal muscle, which leads to better exercise training and increased muscle strength. In this context, the use of GH in healthy elderly should be an option for increasing muscle strength. Our aim was to evaluate the effect of GH therapy on muscle strength in healthy men over 50 years old. Fourteen healthy men aged 50-70 years were evaluated at baseline for body composition and muscle strength (evaluated by leg press and bench press exercises, which focus primarily on quadriceps-lower body part and pectoralis major-upper body part-muscles, resp.). Subjects were randomised into 2 groups: GH therapy (7 subjects) and placebo (7 subjects) and reevaluated after 6 months of therapy. Thirteen subjects completed the study (6 subjects in the placebo group and 7 subjects in the GH group). Subjects of both groups were not different at baseline. After 6 months of therapy, muscle strength in the bench press responsive muscles did not increase in both groups and showed a statistically significant increase in the leg press responsive muscles in the GH group. Our study demonstrated an increase in muscle strength in the lower body part after GH therapy in healthy men. This finding must be considered and tested in frail older populations, whose physical incapacity is primarily caused by proximal muscle weakness. The trial was registered with NCT01853566.

Identification of sarcopenic obesity in postmenopausal women: a cutoff proposal

Sarcopenic obesity is the combination of reduced fat-free mass (FFM) and increased fat mass (FM) with advancing age but there is lack of clear criteria for its identification. The purposes of the present investigation were: 1) to determine the prevalence of postmenopausal women with reduced FFM relative to their FM and height, and 2) to examine whether there are associations between the proposed classification and health-related variables. A total of 607 women were included in this cross-sectional study and were separated into two subsets: 258 older women with a mean age of 66.8 ± 5.6 years and 349 young women aged 18-40 years (mean age, 29.0 ± 7.5 years). All volunteers underwent body composition assessment by dual-energy X-ray absorptiometry. The FFM index relative to FM and height was calculated and the cutoff value corresponded to two standard deviations below the mean of the young reference group. To examine the clinical significance of the classification, all older participants underwent measurements of quadriceps strength and cardiorespiratory fitness. Values were compared between those who were classified as low FFM or not, using an independent samples t-test and correlations were examined. The cutoff corresponded to a residual of -3.4 and generated a sarcopenic obesity prevalence of 19.8 percent that was associated with reduced muscle strength and aerobic fitness among the older participants. Also, the index correlated significantly with the health-related fitness variables. The results demonstrated reduced functional capacity for those below the proposed cutoff and suggested applicability of the approach as a definition for sarcopenic obesity.

Identification of sarcopenic obesity in postmenopausal women: a cutoff proposal.

Sarcopenic obesity is the combination of reduced fat-free mass (FFM) and increased fat mass (FM) with advancing age but there is lack of clear criteria for its identification. The purposes of the present investigation were: 1) to determine the prevalence of postmenopausal women with reduced FFM relative to their FM and height, and 2) to examine whether there are associations between the proposed classification and health-related variables. A total of 607 women were included in this cross-sectional study and were separated into two subsets: 258 older women with a mean age of 66.8 ± 5.6 years and 349 young women aged 18-40 years (mean age, 29.0 ± 7.5 years). All volunteers underwent body composition assessment by dual-energy X-ray absorptiometry. The FFM index relative to FM and height was calculated and the cutoff value corresponded to two standard deviations below the mean of the young reference group. To examine the clinical significance of the classification, all older participants underwent measurements of quadriceps strength and cardiorespiratory fitness. Values were compared between those who were classified as low FFM or not, using an independent samples t-test and correlations were examined. The cutoff corresponded to a residual of -3.4 and generated a sarcopenic obesity prevalence of 19.8% that was associated with reduced muscle strength and aerobic fitness among the older participants. Also, the index correlated significantly with the health-related fitness variables. The results demonstrated reduced functional capacity for those below the proposed cutoff and suggested applicability of the approach as a definition for sarcopenic obesity.

Effects of a supervised exercise program on the physical fitness and immunological function of HIV-infected patients.

AIM: Exercise effects in subjects with HIV/AIDS are not entirely understood. The study aimed to investigate the effects of a supervised exercise program on the physical fitness and immunological function of HIV-infected subjects. METHODS: Twenty-seven highly active antiretroviral therapy treated HIV-infected patients (age: 45±2 years; CD4-T: 21.3±2.2%) were assigned to a control (CG, n=8) or experimental (EG, n=19) group. The EG participated in a 12-week exercise program, consisting of aerobic training, strength, and flexibility exercises (3 times/wk; aerobic-30min: PWC 150; strength-50min: 3 sets of 12 reps of 5 exercises at 60-80% 12 RM; flexibility-10min: 2 sets of 30 s at maximal range of motion of 8 exercises). RESULTS: Prior to training there was no significant difference in any variable between the EG and the CG. Flexibility (23%, P<0.05), 12 repetition maximum in the leg press and seated bilateral row exercises (54% and 65% respectively, P<0.05) increased, while the heart rate at a given cycle ergometer workload declined (19% for slope and 12% for intercept, P<0.05) in the EG, but not in the CG. No significant differences were found for the relative and absolute CD4 T-cell counts between groups prior to or after training, but there was a slight enhancement trend in the EG (16%, P=0.19). CONCLUSION: Overall training can improve the muscle and aerobic fitness of HIV-infected patients with no negative effect on their immunological function.

Influence of cardiopulmonary exercise testing protocol and resting VO(2) assessment on %HR(max), %HRR, %VO(2max) and %VO(2)R relationships.

The findings of previous studies investigating the strength of the relationships between the percentages of maximal heart rate (%HR(max)), heart rate reserve (%HRR), maximal oxygen uptake (%VO(2max)), and oxygen uptake reserve (%VO(2)R) have been equivocal. This inconsistency between studies could largely be due to differences in methodology. The purpose of this study was therefore to determine whether different VO(2max) test protocols and resting VO(2) assessment influence the relationships between the %HR(max), %HRR, %VO(2max), and %VO(2)R. Thirty-three young men performed maximal treadmill protocols (ramp, Bruce) to assess HR(max) and VO(2max). Resting VO(2) was assessed as follows: a) resting VO(2standard), using strict criteria (24 h exercise abstention, alcohol, soft drinks, or caffeine; 8 h fasting; 30 min assessment); b) resting VO(2sitting) and; c) resting VO(2standing) (both 5 min before exercise testing). The %HRR was closer to %VO(2max) than to %VO(2)R, especially in the ramp protocol (p<0.001). In the Bruce protocol, relationships were closer to the identity line, and there was no significant difference between %HRR and %VO(2max), or %VO(2)R. The VO(2max) was significantly higher in the ramp protocol compared to the Bruce protocol (p<0.001). In both protocols resting VO(2) assessment produced no significant difference in the intercepts and slopes of the %HRR-%VO(2)R relationships obtained from individual regression models. The %VO(2)R calculated using resting VO(2standard) was closer to %HRR compared to VO(2sitting) and VO(2standing). The premise that %HRR is more strongly related to %VO(2)R than to %VO(2max) was not confirmed. Methodological differences should be considered when interpreting previous studies investigating %HR(max), %HRR, %VO(2max), and %VO(2)R relationships.

Walk-run transition in young and older adults: with special reference to the cardio-respiratory responses.

Cardio-respiratory responses of young and older subjects performing walking and running protocols at the walk-run transition speed (WRT) were compared. A total of 26 volunteers assigned to younger (YG, 24 +/- 3 years) and older (OG, 64 +/- 6 years) groups underwent a protocol to determine the WRT used in 6-min walking and running protocols. Oxygen uptake (VO(2)), ventilation (V (E)), expired carbon dioxide (VCO(2)), heart rate (HR) and perceived exertion (RPE) were assessed. Oxygen pulse (O(2) pulse) and respiratory exchange ratio (RER) were calculated. The WRT was not different between groups (OG: 6.84 +/- 0.69 km h(-1) vs. YG: 7.04 +/- 0.77 km h(-1), P = 0.62). No between-group differences were found within a given gait pattern for VO(2) (P = 0.061) and VCO(2) (P = 0.076). However, VO(2) (P = 0.0022) and VCO(2) (P = 0.0041) increased in OG when running, remaining stable in YG (VO(2): P = 0.622; VCO(2): P = 0.412). The VE was higher in OG compared to YG in walking (P = 0.030) and running (P = 0.004) protocols. No age-related (P = 0.180) or locomotion (P = 0.407) effects were found for RER. The HR increased in OG and between-group difference was detected while running (P = 0.003). No within- (P = 0.447) or between-group (P = 0.851) difference was found for O(2) pulse. The net VO(2) increased from walking to running in OG (P < 0.0001) but not in YG (P = 0.53), while RPE was lower in YG (P = 0.041) but stable in OG (P = 0.654). In conclusion, the WRT speed was similar across the age groups. However, the VO(2) and VCO(2) increase from walking to running was larger for OG than YG. The HR, VE and RPE were also higher when running in OG compared to YG. Therefore, the locomotion strategy had different impacts on the metabolic demand of older and younger subjects.

Effects of age and rest interval on strength recovery.

The purpose of this study was to compare the effect of two different rest intervals between sets of isokinetic knee extension exercise on peak torque (PT), and Total Work (TW) between untrained younger and older men. Seventeen young men (24.22+/-2.58 yrs) and 20 older men (66.85+/-4.02 yrs) performed 3 sets of 10 unilateral isokinetic knee extension repetitions at 60 degrees /s. The rest intervals between sets were 1 and 2 min. There was a significant decline in PT when 1 and 2 min rest intervals were used for young men, but not when a 2 min rest interval was applied for old men. There was also a significant decline in TW among the 3 sets when 1 and 2 min rest intervals were applied for young men, whereas the decline in TW in older men occurred only between the 2(nd) and 3(rd) sets. PT and TW in the 3(rd) set were significant greater following a 2 min rest interval than a 1 min rest in both young and older men. The present study indicated that non-resistance trained young men may require longer rest interval to recover full PT and TW when compared to older men.

Correlação entre flexibilidade das articulações glenoumerais e coxofemorais e o desempenho funcional de idosas fisicamente ativas / Association between flexibility of the glenohumeral and hip joints and functional performance in active elderly women

OBJETIVO: Investigar a relação entre a flexibilidade da flexão e extensão das articulações glenoumerais (GU) e coxofemorais (CF) e o desempenho funcional (DF) de idosas funcionalmente independentes e fisicamente ativas. MÉTODOS: Determinou-se em 22 voluntárias (idade=70±6 anos) seis conjuntos de amplitudes de movimentos por goniometria ativo-assistida (ADM) na flexão e extensão das GU e CF. O DF foi determinado pelos testes: velocidade de caminhada habitual (VCH) e máxima (VCM); levantar e sentar em cadeira (LSC); Timed up and Go Test (TUGT); vestir blusa (VBL); subir degraus (SE); levantar do decúbito dorsal (LDD); pegar moeda no solo (PMS); teste de caminhada de seis minutos (TC6M). As associações entre as variáveis ADM e o DF foram testadas por técnicas de correlação simples e múltipla. RESULTADOS: Houve correlações significantes (p<0,05) entre as ADM de CF e os testes LSC (r=0,42 e r=0,45), SE (r=0,52 e r=0,53) e TC6M (r=0,58 e r=0,59) (lados direito e esquerdo, respectivamente). A correlação múltipla ratificou esses resultados (r²=0,51; p<0,05), indicando que 51 por cento da variância nos testes deveu-se à ADM de CF. Não houve associações significantes entre as ADMs de GU e os testes de DF. CONCLUSÕES: Verificou-se associação significante entre a flexibilidade ativo-assistida de CF e alguns testes específicos de DF. Nenhuma relação foi identificada para ADM de GU. Estudos adicionais são necessários para elucidar as relações entre flexibilidade passiva de diferentes grupos articulares e a funcionalidade de idosos.

OBJECTIVE: To investigate the relationship between flexibility of flexion and extension of the glenohumeral and coxofemoral joints and functional performance among physically active and functionally independent elderly women. METHODS: Six sets of range of motion (ROM) measurements relating to flexion and extension of the glenohumeral and coxofemoral joints were determined in 22 volunteers (age 70±6 years), using assisted-active goniometry. Functional performance was measured using the following tests: normal walking speed (NWS); maximum walking speed (MWS); sit-to-stand test (SST); timed up and go test (TUGT); putting on a blouse (PBL); going up stairs (GUS); rising from dorsal decubitus (RDD); picking up a coin from the floor (PCF); and 6-minute walk test (6WT). The relationships between the ROM variables and functional performance were tested using simple and multiple regression techniques. RESULTS: There were significant correlations (p<0.05) between coxofemoral ROM and the SST (r=0.42 and r=0.45), GUS (r=0.52 and r=0.53) and 6WT (r=0.58 and r=0.59) (right and left sides, respectively). The multiple regression ratified the results (r²=0.51; p<0.05), thus indicating that coxofemoral ROM accounted for 51 percent of the variance in the tests. There were no significant correlations between the glenohumeral ROMs and the functional performance tests. CONCLUSIONS: There was a significant association between assisted-active flexibility of the coxofemoral joint and some specific functional performance tests. No relationship involving glenohumeral ROM was identified. Additional studies are needed in order to elucidate the relationships between passive flexibility of different joint groups and functional performance in elderly people.

Efeitos de um programa de treinamento resistido com volume e intensidade moderados e velocidade elevada sobre o desempenho funcional de mulheres idosas / Effects of a programme of resistance training with volume and intensity moderates and high speed on functional performance of old women

A tensão muscular pode ser influenciada pela velocidade de movimento, sendo um componente importante da prescrição do treinamento da força em idosos. Esse estudo observou os efeitos de 12 semanas de treinamento resistido (TR), realizado com intensidade e volume moderados e velocidade elevada, porém não explosiva, sobre a força/potência muscular (FM) e o desempenho funcional (DF). Para tal, 24 idosas (68,7±9 anos) fisicamente ativas, foram igualmente distribuídas em grupos controle (GCO) e experimental (GEX). O GEX realizou, 2 X por semana durante 12 semanas, de série única de 10 a 15 repetições de exercícios com intensidade relativa de 50 a 70% de 1RM e fase concêntrica das contrações fixada em menos de 1 seg. O grupo controle não praticou exercícios de força. A FM foi aferida pelo teste de 1RM nos exercícios leg press horizontal (LPH) e flexão dos joelhos na cadeira (CF). Mediu-se o DF através do tempo para realizar as seguintes tarefas: a) caminhada de 10 metros (C10); b) levantar da posição ajoelhada (LPA); c) levantar e sentar de uma cadeira (LSC). Não havia diferenças entre os grupos na linha de base. Ao fim da intervenção, a ANOVA de duas entradas para medidas repetidas seguida da verificação post-hoc de Fisher (p<0,05), demonstrou não haver diferenças significativas para GCO. No GEX foram observados incrementos significativos em todos as medidas de FM (LPH, p<0,0001; CF, p<0,0001) e DF (CAM10, p<0,0001; LSC, p=0,004; LPA, p=0,005). Conclui-se que idosas fisicamente ativas podem ter melhoria significativa de FM e DF em decorrência de TR realizado com intensidade e volume moderados e velocidade elevada.

It has been suggested that lower extremity muscle power and strength are important for physical function in older adults. However, the majority of studies investigating the effects of training on muscle power are based on isokinetic exercises and few studies have determined the effects of isoinertial resistance training (RT) on muscle power and strength and functional performance in older adults. The purpose of the present study was to evaluate the effects of a 12 weeks RT in muscle strength and functional performance in healthy, active, older women. Twentyfour independent and active older women (aged 60-85 years) were assigned either to a control group (CG, n=12), or to a RT group (RTG, n=12). The RTG trained 10 exercises for whole body with one set of 10-15 repetitions at 50 to 70% of 1-repetition maximum (1-RM) released with high-velocity (concentric phase ≤1sec), 2 days per week for 12 weeks. The CG did not perform strength exercises. Both groups were evaluated in 1-RM lower body strength in horizontal leg press (HLP) and knee flexion (KF), maximal walking speed (MWS); kneel rise time (KRT); fivetimes-sit-to-stand test (FTSST) before and after the training period. There was no significant difference between groups in base-line (p<.05). After the 12 weeks, the 2-way ANOVA showed inter and intragroups significant differences (p<.05). RTG significantly increased the results for all 1RM tests: HLP (p<.0001); KF (p<.0001) and physical performance: MWS (p<.0001); KRT (p=.005); FTSST (p=.004). In conclusion, strength training of moderate volume/intensity and high-velocity can promote gains in tasks related with lower extremity muscle power in elder women.