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Aging is associated with neurodegeneration and a loss of muscle function, especially in lower-limb muscles. While caffeine may augment muscle force generation through multiple effects on the central nervous system, no studies have yet compared the effects of caffeine on force-generating capacity between younger and older men, who might respond differently due to age-related changes in the structures on which caffeine acts. In a double-blind, controlled trial, 22 younger (25 ± 5 years) and 21 older (68 ± 6 years) men were tested for isometric plantarflexor torque on two separate days (2–7 days apart) before and 60 min after ingesting 3 mg/kg (∼2 cups of coffee) of caffeine or placebo. No effects of caffeine ingestion on peak torque or rate of torque development were detected in either older or younger men. Therefore, 3 mg/kg of caffeine may not acutely counteract age-related decreases in force capacity of the functionally important plantarflexor muscles.

As a preliminary step in developing the physical-functioning measure of the Late-Life Function and Disability Instrument (LLFDI), the authors compared its items with the physical-functioning items (PF-10) on the SF-36 Health Survey. They compared the item coverage, hierarchy, and scale-separation properties of the PF-10 items with those of the physical-functioning items of the LLFDI. Both questionnaires were administered to 50 community-dwelling older adults. A partial-credit, 1-parameter, item-response-theory model was used to scale the items. The LLFDI improved the range of ability of daily activities that was encompassed by the PF-10 items by 46%. By sequentially deleting new items with poor fit to the overall scale and items with redundant content, the authors developed a scale more capable of accurately assessing low-functioning activities. The LLFDI function component incorporates a broader content range and better person and item separation than the PF-10 items. It appears to have potential as a comprehensive functional-activity assessment for community-dwelling older adults.

The primary purpose of this study was to determine the reproducibility of the 6-min-walk test (6MWT) in older women. A secondary purpose was to document heart rate (HR), blood pressure (BP), and ratings of perceived exertion (RPE) in response to the 6MWT. Twenty-eight women with an average age of 80.0 years (±5.2) participated. They performed 2 trials of the 6MWT on 3 separate days, for a total of 6 trials. Heart rate, BP, RPE, and the total distance walked were recorded for each trial. The results indicated a significant increase from Trial 1 to Trial 2, with no differences between Trials 2–6, F(5, 131) = 7.02, p = .000. HR and BP were consistent across the 6 trials, and RPE was higher for the second trial on the second day of testing, F(5, 131) = 2.72, p = .023. The intraclass correlation coefficient for distance walked was .94. After the initial trial, performance on the 6MWT appears to be stable in older women.

This study used a randomized online survey design to examine the potential influence of ageism on physical activity (PA) prescription for hypothetical patients with prediabetes of different chronological ages. Participants included 356 kinesiology students who were randomly assigned to one of four conditions. Each condition presented a clinical case study of a hypothetical patient with prediabetes referred to the participant as a qualified exercise professional for a PA intervention. Case studies were identical except for the reported patient’s chronological age. Participants provided recommendations for PA support, frequency, duration, and intensity. Significant main effects were observed for PA duration, F(3, 352) = 8.62; p < .001, and intensity, F(3, 352) = 16.20; p < .001. The older patient was prescribed significantly lower PA duration and intensity compared to younger patients and no-age control. This study provides evidence for the presence and independent influence of ageism against older patients in PA prescription for prediabetes management.

Previous research has found that increased physical activity may provide a protective effect on depression status; however, these studies do not account for cognitive function. This study’s aim was to determine whether cognitive function mediates the association between physical activity depression status in older adults. Data from 501 older adults were used for this analysis. Physical activity had a significant protective effect on depression (OR = 0.761, 95% CI [0.65, 0.89], p = .001). Adjusted analysis yielded an attenuated association (OR = 0.81, 95% CI [0.69, 0.95], p = .01) with a significant interaction for physical activity and cognitive function (OR = 0.991, 95% CI [0.985, 0.997], p = .005). MoCA performance also had a significant mediating effect on the relationship between physical activity and depression status (p = .04). These findings suggest that cognitive function is associated with, and does mediate, the relationship between physical activity and depression status.

The purpose of this investigation is to examine differences in rest-activity patterns and sleep characteristics in older adults with heart failure (HF) and healthy older adults. The sample included older adults with HF (n = 20) and a reference group of healthy older adults (n = 20). Traditional cosinor analysis was used to assess three parameters of rest–activity from wrist actigraphy data: amplitude (range of activity), mesor (mean activity), and acrophase (time of peak activity). Traditional sleep characteristics were also determined from actigraphy data: total sleep time (TST), sleep latency (SL), sleep efficiency (SE), and wake after sleep onset (WASO). The HF group demonstrated significantly lower mesor and amplitude than the reference group (p < .01). The HF group had significantly greater TST (p < .01), but the groups had similar SE, SL, and WASO. Despite similar sleep characteristics to healthy older adults, overall rest–activity patterns were significantly dampened in those with HF.

It is widely assumed that healthy aging includes a decline in the stability of standing body sway. Certainly, the spatial magnitude of postural sway increases with age. However, the interpretation of this effect as a decline in the ability to stabilize posture rests, in part, on assumptions about the nature and definition of stability in stance. In this article, I review data on the control of standing posture in healthy older adults. I focus on a growing list of studies that demonstrate the retention, among healthy older adults, of the ability functionally to modulate postural sway in support of “suprapostural” activities. I address laboratory research, but also field studies carried out in a setting that dramatically challenges the control of stance: life on ships at sea. I argue that it may be possible, and certainly will be useful, to address directly the functional control of stance in older adults.