DHEA, DHEA-S and cortisol responses to acute exercise in older adults in relation to exercise training status and sex

The aim of the present study was to investigate resting measures of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulphate (DHEA-S) and cortisol, and the response and recovery of these hormones to acute exercise, in male and female older adults of different exercise training status. Participants were 49 community-dwelling older adults (23 females) aged between 60 and 77 years who were either sedentary (n = 14), moderately active (n = 14) or endurance trained (n = 21). Participants undertook an acute bout of exercise in the form of an incremental submaximal treadmill test. The exercise lasted on average 23 min 49 s (SD = 2 min 8 s) and participants reached 76.5% (SD = 5.44) of the predicted maximal heart rate. Blood samples were collected prior to exercise, immediately, and 1 h post-exercise. DHEA levels significantly increased immediately post-exercise; however, DHEA-S levels only significantly increased in females. Cortisol significantly decreased immediately post-exercise and 1 h post-exercise compared to pre-exercise. There were no significant differences in resting hormone levels or hormonal responses to exercise between training status groups. The findings suggest that exercise can stimulate DHEA production in older adults and that hormonal responses to exercise differ between male and female older adults.     

Aging and physical mobility in group-housed Old World monkeys

While indices of physical mobility such as gait speed are significant predictors of future morbidity/mortality in the elderly, mechanisms of these relationships are not understood. Relevant animal models of aging and physical mobility are needed to study these relationships. The goal of this study was to develop measures of physical mobility including activity levels and gait speed in Old World monkeys which vary with age in adults. Locomotor behaviors of 21 old ( = 20 yoa) and 24 young ( = 9 yoa) socially housed adult females of three species were recorded using focal sample and ad libitum behavior observation methods. Self-motivated walking speed was 17% slower in older than younger adults. Likewise, young adults climbed more frequently than older adults. Leaping and jumping were more common, on average, in young adults, but this difference did not reach significance. Overall activity levels did not vary significantly by age, and there were no significant age by species interactions in any of these behaviors. Of all the behaviors evaluated, walking speed measured in a simple and inexpensive manner appeared most sensitive to age and has the added feature of being least affected by differences in housing characteristics. Thus, walking speed may be a useful indicator of decline in physical mobility in nonhuman primate models of aging.     

The influence of physical exercise and leisure activity on neuropsychological functioning in older adults

It has been suggested that leisure activity and physical exercise can be a protective factor for neuropsychological functions and are associated with a reduced risk of dementia. Thus, the purpose of this study was to investigate the influence of physical exercise and leisure on the neuropsychological functions of healthy older adults. The sample was composed of 51 sedentary female volunteers who were 60–70 years old and were distributed into three groups: A—control, B—leisure, and C—training. Volunteers were submitted to a physical and neuropsychological assessment at baseline and after 6 months. Groups A and B were monitored longitudinally three times a week. Group C improved their neuropsychological functioning and oxygen consumption compared to groups A and B (p = <0.05). The neuropsychological functions of groups A and B were significantly worse after 6 months of monitoring (p = <0.05). The data suggest that physical exercise improves neuropsychological functioning, although leisure activities may also improve this functioning. Thus, an aerobic physical fitness program can partially serve as a non-medication alternative for maintaining and improving these functions in older adults; however, leisure activities should also be considered.     

Validating a widely used measure of frailty: are all sub-components necessary? Evidence from the Whitehall II cohort study

There is growing interest in the measurement of frailty in older age. The most widely used measure (Fried) characterizes this syndrome using five components: exhaustion, physical activity, walking speed, grip strength, and weight loss. These components overlap, raising the possibility of using fewer, and therefore making the device more time- and cost-efficient. The analytic sample was 5,169 individuals (1,419 women) from the British Whitehall II cohort study, aged 55 to 79 years in 2007–2009. Hospitalization data were accessed through English national records (mean follow-up 15.2 months). Age- and sex-adjusted Cox models showed that all components were significantly associated with hospitalization, the hazard ratios (HR) ranging from 1.18 (95 % confidence interval = 0.98, 1.41) for grip strength to 1.60 (1.35, 1.90) for usual walking speed. Some attenuation of these effects was apparent following mutual adjustment for frailty components, but the rank order of the strength of association remained unchanged. We observed a dose–response relationship between the number of frailty components and the risk for hospitalization [1 component—HR = 1.10 (0.96, 1.26); 2—HR = 1.52 (1.26, 1.83); 3–5—HR = 2.41 (1.84, 3.16), P trend <0.0001]. A concordance index used to evaluate the predictive power for hospital admissions of individual components and the full scale was modest in magnitude (range 0.57 to 0.58). Our results support the validity of the multi-component frailty measure, but the predictive performance of the measure is poor.

Electronic supplementary material

The online version of this article (doi:10.1007/s11357-012-9446-2) contains supplementary material, which is available to authorized users.     

Effect of Exercise on Blood Pressure in Type 2 Diabetes: A Randomized Controlled Trial

BACKGROUND

Increased blood pressure (BP) in type 2 diabetes (T2DM) markedly increases cardiovascular disease morbidity and mortality risk compared to having increased BP alone.

OBJECTIVE

To investigate whether exercise reduces suboptimal levels of untreated suboptimal BP or treated hypertension.

DESIGN

Prospective, randomized controlled trial for 6 months.

SETTING

Single center in Baltimore, MD, USA.

PATIENTS

140 participants with T2DM not requiring insulin and untreated SBP of 120–159 or DBP of 85–99 mmHg, or, if being treated for hypertension, any SBP <159 mmHg or DBP < 99 mmHg; 114 completed the study.

INTERVENTION

Supervised exercise, 3 times per week for 6 months compared with general advice about physical activity.

MEASUREMENTS

Resting SBP and DBP (primary outcome); diabetes status, arterial stiffness assessed as carotid-femoral pulse-wave velocity (PWV), body composition and fitness (secondary outcomes).

RESULTS

Overall baseline BP was 126.8 ± 13.5 / 71.7 ± 9.0 mmHg, with no group differences. At 6 months, BP was unchanged from baseline in either group, BP 125.8 ± 13.2 / 70.7 ± 8.8 mmHg in controls; and 126.0 ± 14.2 / 70.3 ± 9.0 mmHg in exercisers, despite attaining a training effects as evidenced by increased aerobic and strength fitness and lean mass and reduced fat mass (all p < 0.05), Overall baseline PWV was 959.9 ± 333.1 cm/s, with no group difference. At 6-months, PWV did not change and was not different between group; exercisers, 923.7 ± 319.8 cm/s, 905.5 ± 344.7, controls.

LIMITATIONS

A completion rate of 81 %.

CONCLUSIONS

Though exercisers improve fitness and body composition, there were no reductions in BP. The lack of change in arterial stiffness suggests a resistance to exercise-induced BP reduction in persons with T2DM.KEY WORDS: exercise training, diabetes, high blood pressure, randomized trial     

Effects of combined exercise on gait variability in community-dwelling older adults

Training that focuses on strength, balance, and endurance, the so-called combined exercise, can enhance physical function, including gait, according to a literature review. However, the effects of combined exercise on improving gait variability are limited. The objective of this study is to investigate the effects of 12 weeks of combined exercise comprised of resistance, endurance, and balance training on gait performance in older adults. Twenty-nine community-dwelling older adults were recruited and assigned to either the experimental group (n = 17) or the control group (n = 12). The 12-week intervention was a combined exercise program at 1 h per day and 3 days per week. The participants received an assessment for both a 6-min walk and gait during both habitual walking and fast walking conditions at pre-intervention and after 8 and 12 weeks of exercise. The 6-min walk was used to assess gait endurance. GAITRite was used to evaluate gait. An analysis of covariance with the pretest score as the covariate was used to determine the difference in each dependent variable between groups. The level of significance was set as p less than 0.05. Our results showed significant between-group effects in the 6-min walk and velocity, stride time, and stride length in both conditions after 8 weeks of exercise and significant between-group effects in the 6-min walk test and all selected gait parameters in both conditions after 12 weeks of exercise. Our findings demonstrate that a 12-week combined exercise program may positively affect gait endurance and gait performance including gait variability in habitual walking and fast walking conditions among older adults. The current study provides important evidence of short-term combined exercise effects on improvements in gait performance.     

Acute exercise increases resistance to oxidative stress in young but not older adults

A single bout of acute exercise increases oxidative stress and stimulates a transient increase in antioxidant enzymes. We asked whether this response would induce protection from a subsequent oxidative challenge, different from that of exercise, and whether the effects were affected by aging. We compared young (20 ± 1 years, n = 8) and older (58 ± 6 years, n = 9) healthy men and women. Resistance to oxidative stress was measured by the F₂-isoprostane response to forearm ischemia/reperfusion (I/R) trial. Each participant underwent the I/R trial twice, in random order; once after performing 45 min of cycling on the preceding day (IRX) and a control trial without any physical activity (IRC). Baseline F₂-isoprostane levels were significantly lower at IRX compared to IRC (P < 0.05) and not different between groups. F₂-isoprostane response to IRX was significantly lower compared to IRC in young (P < 0.05) but not different in the older group. Superoxide dismutase activity in response to acute exercise was significantly higher in young compared to older adults (P < 0.05). These data suggest that signal transduction of acute exercise may be impaired with aging. Repeated bouts of transient reactive oxygen species production as seen with regular exercise may be needed to increase resistance to oxidative stress in older individuals.     

Neuropsychological benefits of stationary bike exercise and a cybercycle exergame for older adults with diabetes: an exploratory analysis

Objective

This quasi-experimental exploratory study investigated neuropsychological effects of exercise among older adults with diabetes mellitus (DM) compared with adults without diabetes (non-DM), and it examined the feasibility of using a stationary bike exergame as a form of exercise for older adults with and without diabetes. It is a secondary analysis that uses a small dataset from a larger randomized clinical trial (RCT) called the Cybercycle Study, which compared cognitive and physiological effects of traditional stationary cycling versus cybercycling.

Methods

In the RCT and the secondary analysis, older adults living in eight independent living retirement facilities in the state of New York were enrolled in the study and assigned to exercise five times per week for 45 min per session (two times per week was considered acceptable for retention in the study) by using a stationary bicycle over the course of 3 months. They were randomly assigned to use either a standard stationary bicycle or a “cybercycle” with a video screen that displayed virtual terrains, virtual tours, and racing games with virtual competitors. For this secondary analysis, participants in the RCT who had type 2 DM (n = 10) were compared with age-matched non-DM exercisers (n = 10). The relationship between exercise and executive function (i.e., Color Trials 2, Digit Span Backwards, and Stroop C tests) was examined for DM and non-DM patients.

Results

Older adults with and without diabetes were able to use cybercycles successfully and complete the study, so the feasibility of this form of exercise for this population was supported. However, in contrast with the larger RCT, this small subset did not demonstrate statistically significant differences in executive function between the participants who used cybercycles and those who used stationary bikes with no games or virtual content on a video screen. Therefore, the study combined the two groups and called them “exercisers” and compared cognitive outcomes for DM versus non-DM patients. As predicted, exercisers with DM exhibited significant gains in executive function as measured by the Color Trails 2 test, controlling for age and education, while non-DM exercisers did not significantly gain in this measure [group × time interaction, F(1,16]) = 9.75; p = .007].

Conclusions

These preliminary results support the growing literature that finds that exercise may improve cognition among older adult with DM. Additional research is needed to clarify why certain aspects of executive function might be differentially affected. The current findings may encourage physicians to prescribe exercise for diabetes management and may help motivate DM patients’ compliance for engaging in physical activity.     

Creatine supplementation and physical training in patients with COPD: A double blind, placebo-controlled study

Study objectives

Patients with chronic obstructive pulmonary disease (COPD) have low exercise capacity and low content of high energetic phosphates in their skeletal muscles. The aim of the present study was to investigate whether creatine supplementation together with exercise training may increase physical performance compared with exercise training in patients with COPD.

Design

In a randomized, double-blind, placebo-controlled study, 23 patients with COPD (forced expiratory volume in one second [FEV₁] < 70% of predicted) were randomized to oral creatine (n = 13) or placebo (n = 10) supplementation during an 8-week rehabilitation programme including exercise training. Physical performance was assessed by Endurance Shuttle Walking Test (ESWT), dyspnea and leg fatigue with Borg CR-10, quality of life with St George’s Respiratory Questionnaire (SGRQ). In addition, lung function test, artery blood gases, grip strength test, muscle strength and fatigue in knee extensors were measured.

Results

COPD patients receiving creatine supplementation increased their average walking time by 61% (ESWT) (p < 0.05) after the training period compared with 48% (p = 0.07) in the placebo group. Rated dyspnea directly after the ESWT decreased significantly from 7 to 5 (p < 0.05) in the creatine group. However, the difference between the groups was not statistically significant neither in walking time nor in rated dyspnea. Creatine supplementation did not increase the health related quality of life, lung function, artery blood gases, grip strength and knee extensor strength/fatigue.

Conclusions

Oral creatine supplementation in combination with exercise training showed no significant improvement in physical performance, measured as ESWT, in patients with COPD compared with exercise training alone.     

Impact of low-volume,high-intensity interval training on maximal aerobic capacity,health-related quality of life and motivation to exercise in ageing men

There is a demand for effective training methods that encourage exercise adherence during advancing age, particularly in sedentary populations. This study examined the effects of high-intensity interval training (HIIT) exercise on health-related quality of life (HRQL), aerobic fitness and motivation to exercise in ageing men. Participants consisted of males who were either lifelong sedentary (SED; N = 25; age 63 ± 5 years) or lifelong exercisers (LEX; N = 19; aged 61 ± 5 years). V˙O2max and HRQL were measured at three phases: baseline (Phase A), week seven (Phase B) and week 13 (Phase C). Motivation to exercise was measured at baseline and week 13. V˙O2max was significantly higher in LEX (39.2 ± 5.6 ml kg min⁻¹) compared to SED (27.2 ± 5.2 ml kg min⁻¹) and increased in both groups from Phase A to C (SED 4.6 ± 3.2 ml kg min⁻¹, 95 % CI 3.1 – 6.0; LEX 4.9 ± 3.4 ml kg min⁻¹, 95 % CI 3.1–6.6) Physical functioning (97 ± 4 LEX; 93 ± 7 SED) and general health (70 ± 11 LEX; 78 ± 11 SED) were significantly higher in LEX but increased only in the SED group from Phase A to C (physical functioning 17 ± 18, 95 % CI 9–26, general health 14 ± 14, 95 % CI 8–21). Exercise motives related to social recognition (2.4 ± 1.2 LEX; 1.5 ± 1.0 SED), affiliation (2.7 ± 1.0 LEX; 1.6 ± 1.2 SED) and competition (3.3 ± 1.3 LEX; 2.2 ± 1.1) were significantly higher in LEX yet weight management motives were significantly higher in SED (2.9 ± 1.1 LEX; 4.3 ± 0.5 SED). The study provides preliminary evidence that low-volume HIIT increases perceptions of HRQL, exercise motives and aerobic capacity in older adults, to varying degrees, in both SED and LEX groups.     

Resistance,Aerobic, and Combination Training on Vascular Function in Overweight and Obese Adults

J Clin Hypertens (Greenwich). 2012; 14:848–854. ©2012 Wiley Periodicals, Inc.The authors investigated the effects of moderate‐intensity resistance, aerobic, or combined exercise on blood pressure and arterial stiffness in overweight and obese individuals compared with no exercise. Participants were randomized to 4 groups: control, aerobic, resistance, and combination. Assessments were made at baseline, week 8, and week 12. In participant‐designated responders, those in the intervention groups who had improved levels of systolic blood pressure (SBP) or augmentation index (AI), we observed a significant decrease of SBP in aerobic (−4%, P=.027), resistance (−5.1%, P=.04), and combination groups (−6.3%, P=.000) at week 8 and in the combination group (−6.3%, P=.005) at week 12, compared with baseline. AI was significantly lower at week 12 in the aerobic (−12%, P=.047), resistance (−9.5%, P=.036), and combination (−12.7%, P=.003) groups compared with baseline, as well as in the combination group (−10.7%, P=.047) compared with the control group. We did not observe significant changes in SBP, DBP, or AI between the interventions when assessing the entire cohort, although there were significant improvements in a subgroup of responders. Thus, some but not all overweight and obese individuals can improve blood pressure and arterial stiffness by participating in regular combination exercise, decreasing the risk of developing cardiovascular disease.

Hypertension is associated with increased risk of coronary heart disease (CHD), stroke, heart failure, and kidney failure. ¹ In Australia, hypertension is a major health problem and data from the 1999–2000 AusDiab study ² indicated that 30% of the population 25 years and older had high systolic (≥140 mm Hg) or diastolic (≥90 mm Hg) blood pressure (BP) or were taking medication to control hypertension. Many people with hypertension go untreated, as there are rarely signs or symptoms of the condition. ³ Higher levels of physical activity are associated with decreased prevalence of hypertension. ³ Endurance training decreases BP due to lower systemic vascular resistance involving the sympathetic nervous system and the renin‐angiotensin system. ⁴ Regular aerobic exercise has also been demonstrated to significantly decrease BP in healthy sedentary normotensive and/or hypertensive adults, ⁵ while other studies have confirmed that resistance training is also beneficial in reducing BP. ⁶ , ⁷ There are limited data, however, on the effect of a combination of aerobic and resistance exercise training on BP.Endurance exercise training is associated with lower levels of stiffness in central arteries, which suggests that regular exercise may be able to delay or prevent age‐related increases in arterial stiffness. ⁸ A single bout of aerobic exercise can improve endothelial function in sedentary ⁹ and physically active individuals. ¹⁰ In addition, the beneficial effects of aerobic training on arterial stiffness and endothelial function have also been observed in numerous studies. ¹¹ , ¹² In contrast, the effect of resistance training has not been studied as extensively as aerobic training, although current data indicate a role in improving endothelial dysfunction. ⁷ Resistance training has also been associated with lower levels of arterial compliance. ¹³ However, a cross‐sectional study by Cooks and colleagues ¹⁴ observed that rowing, which has both aerobic and resistance exercise components, has an overall positive effect on arterial stiffness compared with sedentary controls.There is much evidence supporting the beneficial effects of aerobic exercise on BP and arterial stiffness, but limited data on the effect of other exercise types such as resistance or a combination of aerobic and resistance training. Thus, the aim of this study was to investigate the chronic effects of resistance, aerobic, or combined exercise at moderate intensity on BP and arterial stiffness in overweight and obese individuals compared with no exercise.     

Linkage and association of successful aging to the 6q25 region in large Amish kindreds

Successful aging (SA) is a multidimensional phenotype involving living to older age with high physical function, preserved cognition, and continued social engagement. Several domains underlying SA are heritable, and identifying health-promoting polymorphisms and their interactions with the environment could provide important information regarding the health of older adults. In the present study, we examined 263 cognitively intact Amish individuals age 80 and older (74 SA and 189 “normally aged”) all of whom are part of a single 13-generation pedigree. A genome-wide association study of 630,309 autosomal single nucleotide polymorphisms (SNPs) was performed and analyzed for linkage using multipoint analyses and for association using the modified quasi-likelihood score test. There was evidence for linkage on 6q25-27 near the fragile site FRA6E region with a dominant model maximum multipoint heterogeneity LOD score = 3.2. The 1-LOD-down support interval for this linkage contained one SNP for which there was regionally significant evidence of association (rs205990, p = 2.36 × 10⁻⁵). This marker survived interval-wide Bonferroni correction for multiple testing and was located between the genes QKI and PDE10A. Other areas of chromosome 6q25-q27 (including the FRA6E region) contained several SNPs associated with SA (minimum p = 2.89 × 10⁻⁶). These findings suggest potentially novel genes in the 6q25-q27 region linked and associated with SA in the Amish; however, these findings should be verified in an independent replication cohort.

Electronic supplementary material

The online version of this article (doi:10.1007/s11357-012-9447-1) contains supplementary material, which is available to authorized users.     

Exercise effects on bone mineral density in older adults: a meta-analysis of randomized controlled trials

The purpose of the study was to assess the effects of exercise interventions with different impact loading characteristics on lumbar spine (LS) and femoral neck (FN) bone mineral density (BMD) in older adults. We searched electronic databases and hand searched selected journals up to February 2011 for randomized controlled trials (RCTs) investigating the effects of impact exercise interventions on LS and FN BMD in older adults. Exercise protocols were categorized according to impact loading characteristics. Weighted mean difference (WMD) meta-analyses were undertaken. Heterogeneity amongst trials and publication bias was tested. Random-effects models were applied. Trial quality assessment was also undertaken. Nineteen RCTs, including 1577 subjects, met the inclusion criteria. Twenty-two study group comparisons reported BMD data at the LS. Meta-analysis showed a significant change in BMD at this site (WMD 0.011 g/cm², 95% CI 0.003 to 0.020; p = 0.007), although results were moderately inconsistent (I² = 52.2%). BMD data at the FN were available from 19 study group comparisons among older adults. Results were inconsistent (I² = 63.6%) in showing a significant positive effect of exercise on BMD at this site (WMD 0.016 g/cm², 95% CI 0.005 to 0.027; p = 0.004). Combined loading studies of impact activity mixed with high-magnitude joint reaction force loading through resistance training were effective at LS (WMD 0.016 g/cm², 95% CI 0.002 to 0.036; p = 0.028), and no inconsistency existed among these trials. Odd-impact protocols were also effective in increasing BMD at LS (WMD 0.039 g/cm², 95% CI 0.002 to 0.075; p = 0.038) and FN (WMD 0.036 g/cm², 95% CI 0.012 to 0.061; p = 0.004), although heterogeneity was evident (I² = 87.5% and I² = 83.5%, respectively). We found consistency among results for low-impact and resistance exercise studies on LS and FN, although non-significant BMD changes were evident amongst these types of protocols at any site and amongst the RCTs that provided a combined loading impact exercise at FN. Funnel plots showed no evidence of publication bias. Trial quality was moderate to high. The findings from our meta-analysis of RCTs support the efficacy of exercise for increasing LS and FN BMD in older adults.     

Effect of increased fruit and vegetable consumption on physical function and muscle strength in older adults

Fruit and vegetable (FV) intake, which is often low in older people, may be associated with improved muscle strength and physical function. However, there is a shortage of intervention trial evidence to support this. The current study examined the effect of increased FV consumption on measures of muscle strength and physical function among healthy, free-living older adults. A randomized controlled intervention study was undertaken. Eighty-three participants aged 65–85 years, habitually consuming ≤2 portions of FV/day, were randomised to continue their normal diet (≤2 portions/day), or to consume ≥5 portions of FV/day for 16 weeks. FV were delivered to all participants each week, free of charge. Compliance was monitored at baseline, 6, 12 and 16 weeks by diet history and by measuring biomarkers of micronutrient status. Grip strength was measured by a hand-held dynamometer, while lower-extremity physical function was assessed by performance-based measures. Eighty-two participants completed the intervention. The 5 portions/day group showed greater change in daily FV consumption compared to the 2 portions/day group (P < 0.001). This was reflected in significant increases in biomarkers of micronutrient status. No significant differences were evident in change in physical function between the two groups. However, there was a trend towards a greater change in grip strength in the 5 portions/day compared to the 2 portions/day group (mean change at 16 weeks ± SD, 2.04 ± 5.16 and 0.11 ± 3.26 kg, respectively, P = 0.06). Increased FV consumption may modestly increase grip strength but has no effect on physical function in healthy older adults.     

Growing older with health and vitality: a nexus of physical activity,exercise and nutrition

The preservation of skeletal muscle mass and strength with advancing age are, we propose, critical aspects of ageing with health and vitality. Physical inactivity and poor nutrition are known to accelerate the gradual age-related decline in muscle mass and strength—sarcopenia—however, both are subject to modification. The main purpose of this review is to present the latest, evidence-based recommendations for physical activity and exercise, as well as diet for older adults that would help in preserving muscle mass and strength. We take the position that future physical activity/exercise guidelines need to make specific reference to resistance exercise and highlight the benefits of higher-intensity aerobic exercise training, alongside advocating older adults perform aerobic-based physical activity and household tasks (e.g., carrying groceries). In terms of dietary recommendations, greater emphasis should be placed on optimal rather than minimum protein intakes for older adults. Indeed, guidelines that endorse a daily protein intake of 1.2–1.5 g/kg BM/day, which are levels 50–90 % greater than the current protein Recommendation Dietary Allowance (0.8 g/kg BM/day), are likely to help preserve muscle mass and strength and are safe for healthy older adults. Being cognisant of factors (e.g., reduced appetite) that may preclude older adults from increasing their total daily protein intake, we echo the viewpoint of other active researchers in advocating that protein recommendations for older adults be based on a per meal approach in order to maximize muscle protein synthesis (MPS). On this basis, assuming three meals are consumed daily, a protein dose of 0.4–0.5 g/kg BM should be contained in each meal. We are beginning to understand ways in which to increase the utilization of ingested protein for the stimulation of MPS, namely by increasing the proportion of leucine contained in a given dose of protein, co-ingesting other nutrients (e.g., carbohydrate and fat or supplementation with n-3 polyunsaturated fatty acids) or being physically active prior to protein intake. Clearly, developing simple lifestyle interventions targeted at preserving muscle mass and strength with advancing age is crucial for facilitating longer, healthier lives into older age.     

Oxidative stress in older adults: effects of physical fitness

Acute exercise results in transient change in redox balance. High concentrations of reactive oxygen species (ROS) can lead to oxidative damage to macromolecules. However, moderate periodic increases in ROS, such as experienced with habitual exercise, may activate signal transduction pathways which stimulate increases in endogenous antioxidant systems. This study tested the hypothesis that physically fit older adults would have less oxidative stress than unfit age-matched controls, due to greater circulating concentrations of non-enzymatic antioxidants and greater capacity to upregulate antioxidant enzymes. We compared 37 fit (mean age 65.2 ± 5 years) and 35 unfit (mean age 67.7 ± 4 years) men and women. Fitness status was classified by VO_2 max and maximal leg power. Basal levels of oxidative stress were assessed by measuring urinary markers of nucleic acid damage and lipid peroxidation. Antioxidant status was assessed by measuring total antioxidant power and ratios of reduced to oxidized glutathione in plasma, at rest. The capacity to counteract an oxidative insult was assessed by measuring changes in plasma F₂-isoprostanes in response to forearm ischemia–reperfusion. The fit individuals had significantly lower levels of urinary markers of oxidative damage (all P <0.05) and lower F₂-isoprostane response to the oxidative challenge (P < 0.05), but there were no group differences in antioxidant status. The lower levels of oxidative stress in the fit individuals were not mediated by known effects of exercise training such as adiposity, HDL concentrations, or small molecular weight antioxidants. These data suggest that reduced oxidative stress associated with physical fitness results from differences in activity of antioxidant enzymes.

Electronic supplementary material

The online version of this article (doi:10.1007/s11357-011-9277-6) contains supplementary material, which is available to authorized users.     

Comparison of quadriceps strength and handgrip strength in their association with health outcomes in older adults in primary care

Sarcopenia is thought to play a major role in the functional impairment that occurs with old age. In clinical practice, sarcopenia is often determined by measuring handgrip strength. Here, we compared the lower limb quadriceps strength to the handgrip strength in their association with health outcomes in older adults in primary care. Our study population consisted of older adults (n = 764, 68.2 % women, median age 83) that participated in the Integrated Systemic Care for Older People (ISCOPE) study. Participants were visited at baseline to measure quadriceps strength and handgrip strength. Data on health outcomes were obtained at baseline and after 12 months (including life satisfaction, disability in daily living, GP contact-time and hospitalization). Quadriceps strength and handgrip strength showed a weak association (β = 0.42 [95 % CI 0.33–0.50]; R² = 0.17). Quadriceps strength and handgrip strength were independently associated with health outcomes at baseline, including quality of life, disability in daily living, GP contact-time, hospitalization, and gait speed. Combined weakness of the quadriceps and handgrip distinguished a most vulnerable subpopulation that presented with the poorest health outcomes. At follow-up, handgrip strength showed an association with quality of life (β = 0.05; P = 0.002) and disability in daily living (β = −0.5; P = 0.004). Quadriceps weakness did not further contribute to the prediction of the measured health outcomes. We conclude that quadriceps strength is only moderately associated with handgrip strength in an older population and that the combination of quadriceps strength and handgrip strength measurements may aid in the identification of older adults in primary care with the poorest health outcomes. In the prediction of poor health outcomes, quadriceps strength measurements do not show an added value to the handgrip strength.     

Effect of upper extremity exercise in people with COPD

Background

Exercise for people with COPD has focused on leg training, such as walking and cycling. The role and effectiveness of arm training has not been investigated in detail. This review was undertaken to examine the literature for the effectiveness of upper extremity exercise on arm exercise capacity and arm strength in people with COPD.

Methods

Trials relating to arm endurance and strength training in COPD were located by searching electronic databases and screening the reference lists of pertinent articles. Where possible, effect sizes and 95% CI were determined and meta-analysis used.

Results

The search strategy yielded 24 articles. Unsupported arm training improved arm endurance capacity (standard mean difference [SMD] =1.25; 95% CI=0.16 to 2.66) and was the optimal mode of arm endurance training. Combined unsupported and supported arm training was also found to have a large positive effect on peak arm exercise capacity (SMD=1.27; 95% CI=0.59 to 1.94). In addition arm strength training produced moderate improvements in arm strength (SMD=0.46; 95% CI=0.10 to 0.81).

Conclusion

This review suggests that in the short term, arm endurance training improves arm exercise capacity and arm strength training improves arm strength. Further research is required, in people with COPD, to investigate the long-term effects of arm training.     

Enhancing Care for Hospitalized Older Adults with Cognitive Impairment: A Randomized Controlled Trial

Background

Approximately 40% of hospitalized older adults have cognitive impairment (CI) and are more prone to hospital-acquired complications. The Institute of Medicine suggests using health information technology to improve the overall safety and quality of the health care system.

Objective

Evaluate the efficacy of a clinical decision support system (CDSS) to improve the quality of care for hospitalized older adults with CI.

Design

A randomized controlled clinical trial.

Setting

A public hospital in Indianapolis.

Population

A total of 998 hospitalized older adults were screened for CI, and 424 patients (225 intervention, 199 control) with CI were enrolled in the trial with a mean age of 74.8, 59% African Americans, and 68% female.

Intervention

A CDSS alerts the physicians of the presence of CI, recommends early referral into a geriatric consult, and suggests discontinuation of the use of Foley catheterization, physical restraints, and anticholinergic drugs.

Measurements

Orders of a geriatric consult and discontinuation orders of Foley catheterization, physical restraints, or anticholinergic drugs.

Results

Using intent-to-treat analyses, there were no differences between the intervention and the control groups in geriatric consult orders (56% vs 49%, P = 0.21); discontinuation orders for Foley catheterization (61.7% vs 64.6%, P = 0.86); physical restraints (4.8% vs 0%, P = 0.86), or anticholinergic drugs (48.9% vs 31.2%, P = 0.11).

Conclusion

A simple screening program for CI followed by a CDSS did not change physician prescribing behaviors or improve the process of care for hospitalized older adults with CI.

Electronic supplementary material

The online version of this article (doi:10.1007/s11606-012-1994-8) contains supplementary material, which is available to authorized users.KEY WORDS: cognitive impairment, clinical trial, decision support, hospitalized elders