Cross-validation of the recumbent stepper submaximal exercise test to predict peak oxygen uptake in older adults.

BACKGROUND: Submaximal exercise testing can have a greater application in clinical settings because peak exercise testing is generally not available. In previous work, a prediction equation was developed to estimate peak oxygen consumption (Vo2) using a total body recumbent stepper (TBRS) and the Young Men's Christian Association (YMCA) protocol in adults who were healthy. OBJECTIVE: The purpose of the present study was to cross-validate the TBRS peak Vo2 prediction equation in older adults. DESIGN: A cross-sectional study was conducted. METHODS: Thirty participants (22 female, 8 male; mean age=66.8 years, SD=5.52; mean weight=68.51 kg, SD=13.39) who previously completed a peak exercise test and met the inclusion criteria were invited to participate in the cross-validation study. Within 5 days of the peak Vo2 test, participants completed the TBRS submaximal exercise test. The TBRS submaximal exercise test equation was used to estimate peak Vo2. The variables in the equation included age, weight, sex, watts (at the end of the submaximal exercise test), and heart rate (at the end of the submaximal exercise test). RESULTS: A strong correlation was found between the predicted peak Vo2 and the measured peak Vo2. The difference between the values was 0.9 mL·kg(-1)·min(-1), which was not statistically different. The standard error of the estimate was 4.2 mL·kg(-1)·min(-1). LIMITATIONS: The sample included individuals who volunteered to perform a peak exercise test, which may have biased the results toward those willing to exercise to fatigue. CONCLUSION: The data suggest the TBRS submaximal exercise test and prediction equation can be used to predict peak Vo2 in older adults. This finding is important for health care professionals wanting to provide information to their patients or clients regarding their fitness level.

Submaximal and peak cardiorespiratory response after moderate-high intensity exercise training in subacute stroke.

PURPOSE: Reduced cardiovascular fitness post-stroke may negatively impact recovery. There is little information regarding exercise testing performance and cardiorespiratory response to an aerobic exercise intervention in subacute stroke. The purpose of this study was to examine cardiorespiratory response in subacute stroke after an 8-week aerobic exercise intervention using a total body recumbent stepper (TBRS). METHODS: Nine individuals with mean age 61.2 (SD 4.7) years and mean 66.7 (SD 41.5) days post-stroke completed the exercise intervention. Participants had a mean Fugl-Meyer score of 100.3 (SD 29.3). Outcome measures were obtained at baseline and postintervention. A peak exercise test using a TBRS assessed oxygen consumption, heart rate, and minute ventilation. Participants completed an 8-week exercise intervention on a recumbent stepper 3 times per week at a prescribed heart rate intensity. RESULTS: Submaximal VO2 was significantly lower from baseline to postintervention with a main effect of Study Visit (F1,8 = 8.5, p = 0.02). Heart rate was not significantly different pre- to postintervention. Minute ventilation exhibited no main effect of Study Visit or Test Minute. CONCLUSION: Moderate-high intensity aerobic exercise in subacute stroke appears to be beneficial for improving cardiovascular outcomes during submaximal performance of an exercise test.

The role of patient demographics and clinical presentation in predicting discharge placement after inpatient stroke rehabilitation: analysis of a large, US data base.

PURPOSE: To determine whether functional ability at admission and demographics predict discharge placement after inpatient rehabilitation for older adults recovering from stroke. METHOD: In this retrospective study, we examined records of 31,910 adults 65 years of age and older who were admitted for inpatient rehabilitation post-stroke. Binary logistic regression was used with the outcome of placement and potential predictors of the admission Functional Independence Measure (FIM) score, age, sex and marital status. RESULTS: The average admission FIM was 60.0 out of 126; the average FIM at discharge was 84.8. The mean age was 77.7 ± 7.3 years, 57% were female and 52.5% were not married. More than three quarters of the patients were discharged to home. Odds ratios (ORs) with 95% confidence intervals (CIs) showed that patients with a FIM score below the mean of our sample (OR = 5.8, CI = 5.5-6.2), older than the mean age of our sample (OR = 1.6, CI = 1.5-1.7), and who were not married (OR = 1.9, CI = 1.8-2.0) (p-values <0.001) were more likely to be discharged to residential care. Sex was not predictive of placement. CONCLUSION: The admission FIM was an important predictor of discharge placement after rehabilitation in older adults. Age and marital status were also significant predictors of discharge placement. Sex was not a significant predictor.

Aerobic exercise in subacute stroke improves cardiovascular health and physical performance.

BACKGROUND AND PURPOSE: Cardiovascular health is often impaired after stroke. Reduced exercise capacity ((Equation is included in full-text article.)VO(2peak)) and changes in the vascular system in the stroke-affected limb may impact performance of physical activities such as walking. There is little information regarding the role of prescribed moderate- to high-intensity exercise in subacute stroke. The purpose of this study was to examine whether an 8-week aerobic exercise intervention would improve cardiovascular health and physical performance in participants with subacute stroke. METHODS: Ten subjects were enrolled in the study and 9 of them completed the intervention. Participants were aged 61.2 ± 4.7 years old, were 66.7 ± 41.5 days poststroke, and had minor motor performance deficits (Fugl-Meyer score, 100.3 ± 29.3). Outcome measures were taken at baseline, postintervention, and at 1-month follow-up. Brachial artery vasomotor reactivity (flow-mediated dilation [FMD]) of both arms was used to assess vascular health, and a peak exercise test was used to assess exercise capacity. The 6-minute walk test (6MWT) was used to assess physical performance. Participants exercised on a recumbent stepper 3 times per week for 8 weeks at a prescribed heart rate intensity. RESULTS: At baseline, we identified between-limb differences in brachial artery FMD and low (Equation is included in full-text article.)VO(2peak) values. After the intervention, significant improvements were observed in the FMD in both arms, resting systolic blood pressure, and the 6MWT. Although we also observed improvements in the resting diastolic blood pressure, heart rate, and (Equation is included in full-text article.)VO(2peak) values, these changes were not significantly different. DISCUSSION AND CONCLUSION: Aerobic exercise in participants with subacute stroke was beneficial for improving cardiovascular health, reducing cardiac risk, and improving physical performance (6MWT).

Recumbent stepper submaximal exercise test to predict peak oxygen uptake.

PURPOSE: The purpose of this study was to examine the ability of the YMCA submaximal exercise test protocol using a total body recumbent stepper to predict V˙O(2peak). METHODS: Of 112 individuals initially screened, 110 individuals with low to moderate cardiovascular disease risk met the inclusion criteria for participation in the study. The maximal exercise test used a motorized treadmill and the Bruce or modified Bruce protocol. Oxygen uptake was measured and analyzed through collection of expired gases using a metabolic measurement system. The submaximal exercise test was performed at least 24 h later but no more than 5 d after maximal exercise testing. Participants were instructed to keep a pace of 100 steps per minute and the resistance increase every 3 min according to the protocol until fatigue, or until 85% of HR max was achieved. A cross-validation study was also performed to determine the accuracy of the prediction equation. RESULTS: Using a stepwise regression, we report that V˙O(2peak) can be predicted using a five-element model including age, weight, sex, wattsend_submax, and HRend_submax (F5,69 = 70.31, P < 0.001). We report a strong correlation between the predicted V˙O(2peak) to the actual V˙O(2peak). CONCLUSIONS: These data suggest the YMCA submaximal exercise test can be used with the total body recumbent stepper to predict V˙O(2peak) in healthy adults.

Measures of Cardiovascular Health and Physical Function after an Aerobic Exercise Intervention in a Patient Fifteen Days Post-Stroke.

Study Design: Case Study Background: Changes in cardiorespiratory (CR) fitness post-stroke severely impact an individual's quality of life. The purpose of this case study was to demonstrate whether a moderate to high intensity aerobic exercise program would improve cardiovascular fitness, and physical performance measures in a participant following discharge from acute stroke rehabilitation. The participant is a 58 year-old female who experienced an ischemic stroke 15 days prior to beginning the exercise intervention. Case Description: The participant was provided a supervised 8-week exercise intervention on a Total Body Recumbent Stepper (TBRS). The exercise intervention consisted of three sessions per week; the first 4 weeks the participant exercised at a moderate intensity of 50-59% heart rate reserve (HRR) calculated from the baseline exercise test; the last 4 weeks the intensity was increased to 60-69% HRR. Exercise duration began at 20 minutes with the goal of reaching 30 minutes of continuous exercise at a specified workload. Outcomes: Following 8-weeks of intervention, the participant showed improvement in cardiovascular measures including: resting blood pressure (BP), resting heart rate (HR), VO2 peak, and the maximum distance walked (6-MWT). Conclusion: The use of a moderate to high intensity aerobic exercise intervention may be effective for participants in the sub-acute phase of stroke recovery in order to improve cardiovascular health and physical function.

Primary somatosensory cortex in chronic low back pain - a H-MRS study.

The goal of this study was to investigate whether certain metabolites, specific to neurons, glial cells, and the neuronal-glial neurotransmission system, in the primary somatosensory cortex (SSC), are altered and correlated with clinical characteristics of pain in patients with chronic low back pain (LBP). Eleven LBP patients and eleven age-matched healthy controls were included. N-acetylaspartate (NAA), choline (Cho), myo-inositol (mI), and glutamine/glutamate (Glx) were measured with proton magnetic resonance spectroscopy ((1)H-MRS) in left and right SSC. Differences in metabolite concentrations relative to those of controls were evaluated as well as analyses of metabolite correlations within and between SSCs. Relationships between metabolite concentrations and pain characteristics were also evaluated. We found decreased NAA in the left SSC (P = 0.001) and decreased Cho (P = 0.04) along with lower correlations between all metabolites in right SSC (P = 0.007) in LBP compared to controls. In addition, we found higher and significant correlations between left and right mI (P < 0.001 in LBP vs P = 0.1 in controls) and between left mI and right Cho (P = 0.048 vs P = 0.6). Left and right NAA levels were negatively correlated with pain duration (P = 0.04 and P = 0.02 respectively) while right Glx was positively correlated with pain severity (P = 0.04). Our preliminary results demonstrated significant altered neuronal-glial interactions in SSC, with left neural alterations related to pain duration and right neuronal-glial alterations to pain severity. Thus, the (1)H-MRS approach proposed here can be used to quantify relevant cerebral metabolite changes in chronic pain, and consequently increase our knowledge of the factors leading from these changes to clinical outcomes.