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Reto W Kressig

Publications and source records attributed to Reto W Kressig.

13 recordsLinked to original sources
PubMed2006

Relationships between dual-task related changes in stride velocity and stride time variability in healthy older adults.

Dual-task related gait changes have been previously reported for healthy older adults, suggesting that gait control requires attention. Compared to balance control, the involvement of attention in the control of the rhythmic stepping mechanism, as reflected by stride time variability, is not well known. In particular, under dual-task, the relative contributions of a second, attention-demanding task and changes in walking speed remain unclear. Thus, the aims of this study were (1) to assess whether walking with a slow-selected speed or walking while performing an attention-demanding task affected stride time variability in a sample of healthy older participants, and (2) to establish whether stride time variability under dual-task conditions is related either to the decrease of walking speed or the simultaneous attention-demanding task, or to both. Forty-five healthy older participants performed four experimental conditions: (1) walking at a normal self-selected speed, (2) walking at a slow self-selected speed, (3) performing a verbal fluency task when sitting on a chair, and (4) performing the verbal fluency task while walking at self-selected walking speed. Gait parameters were recorded across 15 meters, using Physilog. Results showed a significant dual-task related decrease in mean values of stride velocity, as well as a significant increase in mean values and coefficients of variation of stride time. These dual-task related changes in stride time were explained by the simultaneous performance of the verbal fluency task, the decrease of gait speed and the variability between participants. Although a relationship exists between decreased walking speed and increased stride time variability, the dual-task related increase of stride time variability was also significantly associated with the attention-demanding task, suggesting some attentional control for the rhythmic stepping mechanism of walking in healthy older adults.

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PubMed2006

Guidelines for clinical applications of spatio-temporal gait analysis in older adults.

Quantifying spatio-temporal gait parameters in stationary and ambulatory geriatric settings may aid the early identification of potential fallers, as well as the documentation of illness-specific gait disorders and intervention-related changes in rehabilitative medicine. Bringing gait analysis out of the laboratory and into a clinical setting is the goal of the European GAITRite network group, initiated in 2003 in Geneva. To enhance reproducibility of gait measures and for better comparability of outcomes in clinical environments, a consensus on data collection was formulated and presented at the 2nd European GAITRite Meeting in Marseilles. The guidelines presented here are intended to facilitate network collaborations and to provide guidance to clinicians who wish to implement spatio-temporal gait analysis in clinical settings.

Accidental Falls↗
PubMed2006

The influence of intense Tai Chi training on physical performance and hemodynamic outcomes in transitionally frail, older adults.

BACKGROUND: Few data exist to evaluate whether Tai Chi (TC) training improves physical performance and hemodynamic outcomes more than a wellness education (WE) program does among older fallers transitioning to frailty. METHODS: This 48-week randomized clinical trial was provided at 10 matched pairs of congregate living facilities in the Atlanta metropolitan area to 291 women and 20 men, who were transitionally frail, >or=70 years old, and had fallen at least once within the past year. Pairs of facilities were randomized to either TC exercise (n = 158) or WE (control) interventions (n = 153) over 48 weeks. Physical performance (freely chosen gait speed, reach, chair-rises, 360 degrees turn, picking up an object from the floor, and single limb support) and hemodynamic outcomes (heart rate and blood pressure) were obtained at baseline and after 4, 8, and 12 months. RESULTS: Mean percent change (baseline to 1 year) for gait speed increased similarly in both cohorts (TC: 9.1% and WE: 8.2%; p =.78). However, time to complete three chair-rises decreased 12.3% for TC and increased 13.7% for WE (p =.006). Baseline to 1 year mean percent change decreased among TC and increased within WE cohorts for: body mass index (-2.3% vs 1.8%; p <.0001), systolic blood pressure (-3.4% vs 1.7%; p =.02), and resting heart rate (-5.9% vs 4.6%; p <.0001). CONCLUSIONS: TC significantly improved chair-rise and cardiovascular performance. Because TC training reduced fall occurrences in this cohort, factors influencing functional and cardiovascular improvements may also favorably impact fall events.

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PubMed2005

Stride-to-stride variability while backward counting among healthy young adults.

BACKGROUND: Little information exists about the involvement of attention in the control of gait rhythmicity. Variability of both stride time and stride length is closely related to the control of the rhythmic stepping mechanism. We sought 1) to determine whether backward counting while walking could provoke significant gait changes in mean values and coefficients of variation of stride velocity, stride time and stride length among healthy young adults; and 2) to establish whether change in stride-to-stride variability could be related to dual-task related stride velocity change, attention, or both. METHODS: Mean values and coefficients of variation of stride velocity, stride time and stride length were recorded using the Physilog-system, at a self-selected walking speed in 49 healthy young adults (mean age 24.1 +/- 2.8 years, women 49%) while walking alone and walking with simultaneous backward counting. Performance on backward counting was evaluated by recording the number of figures counted while sitting alone and while walking. RESULTS: Compared with walking alone, a significant dual-task-related decrease was found for the mean values of stride velocity (p < 0.001), along with a small but significant increase for the mean values and coefficients of variation of stride time (p < 0.001 and p = 0.015, respectively). Stride length parameters did not change significantly between both walking conditions. Dual-task-related increase of coefficient of variation of stride time was explained by changing stride velocity and variability between subjects but not by backward counting. The number of figures counted while walking decreased significantly compared to backward counting alone. Further, the dual-task related decrease of the number of enumerated figures was significantly higher than the dual-task related decrease of stride velocity (p = 0.013). CONCLUSION: The observed performance-changes in gait and backward counting while dual tasking confirm that certain aspects of walking are attention-demanding in young adults. In the tested group of 49 young volunteers, dual tasking caused a small decrease in stride velocity and a slight increase in the stride-to-stride variability of stride time, while stride velocity variability was not affected by the attention-demanding task. The increase in stride time variability was apparently the result of a change in gait speed, but not a result of dual tasking. This suggests that young adults require minimal attention for the control of the rhythmic stepping mechanism while walking.

Journal Article↗
PubMed2005

Relationship between dual-task related gait changes and intrinsic risk factors for falls among transitional frail older adults.

BACKGROUND AND AIMS: Gait changes in dual-task conditions have been associated with an increased risk of falling in older adults, and become more important in increasingly frail older adults. We studied the relationship between commonly known intrinsic risk factors for falls and dual-task related gait changes among transitional frail older adults. METHODS: Walking time and number of steps were measured while walking alone and while walking with counting backward on a 10-m walkway in 66 transitional frail older adults (mean age 83.6+/-6.1, 84.9% women). Uni- and multiple linear regression analyses were performed to explore the relationship between dual-task related gait changes (walking time and number of steps) and age over 85 years, polymedication, psychoactive drugs, poor distance vision, abnormal mobility and cognitive impairment. RESULTS: Compared with walking alone, both walking time and number of steps increased significantly while counting backward (p<0.001). Polymedication and abnormal mobility were associated with a significant increase of walking time and number of steps (p<0.01 for unadjusted change, p<0.05 for adjusted change). CONCLUSIONS: Dual-task related gait changes were closely correlated with polymedication and impaired mobility in our sample of transitional frail older adults. These findings give some insight into the complexity of performing attention-demanding tasks while walking and accentuate the need for multi-factorial, personalized intervention strategies, to prevent decline in dual-task performance in this fall-prone population.

Accidental Falls↗
PubMed2004

Temporal and spatial features of gait in older adults transitioning to frailty.

Examining gait characteristics in older adults who are transitioning to frailty enhances our understanding of movement control in this fall-prone population and helps to better target preventive interventions. This work presents data on temporal and spatial gait parameters of a group of older adults who have been operationally defined as "transitionally frail". Gait speed, cadence, stride length, stance, swing, double-support, and horizontal heel velocity at heel contact were measured in 50 transitionally frail older adults while walking at a self-selected pace. These data suggest that the temporal and spatial gait features of these older adults differ substantially from published results from other older adults.

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PubMed2003

[T'ai chi in the elderly: practical aspects].

New approaches to health promotion for the growing geriatric population are needed. Low to moderately intense exercise programs, such as T'ai Chi seem particularly appropriate for older individuals because of many worthwhile physiological and psychological long-term benefits. T'ai Chi reduces falls and improves postural stability in older adults. It also has a positive impact on muscle strength and cardiovascular fitness and can improve mobility in patients with rheumatoid arthritis. It imparts a sense of well-being and confidence, and can reduce fear of falling in older adults. This article reviews the current medical literature regarding the multiple effects of T'ai Chi. Historical aspects of T'ai Chi and its current adaptation for practice by healthy older adults are presented. Finally, a set of modified exercises is proposed that is based on underlying principles of T'ai Chi and can be applied to patients with mild to moderate cognitive impairment.

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PubMed2002

Exercise prescribing: computer application in older adults.

PURPOSE: The purpose of this study was to determine if older adults are capable and willing to interact with a computerized exercise promotion interface and to determine to what extent they accept computer-generated exercise recommendations. DESIGN AND METHODS: Time and requests for assistance were recorded while 34 college-educated volunteers, equal numbers of men and women, ranging in age from 60 to 87, interfaced with a health promotion tool. The computerized exercise promotion tool's ease of use and the acceptability of the exercise recommendations made were rated by the participants. RESULTS: On average, completion of the items on the computer took 33 min and each participant made 3 requests for assistance, of which only 22% were mouse related. The system's ease of use and the exercise prescription acceptability ratings were high and independent of prior experience with computers. IMPLICATIONS: User friendliness of computerized health promotion tools will determine if, and how, health providers integrate these new technologies into daily practice. The participants in the study were able to complete the computerized items within a reasonable amount of time and with minimal assistance from the provider. These data support the potential of interactive technology in health promotion among the expanding older population.

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PubMedDate not supplied

Dual-task-related gait changes in transitionally frail older adults: the type of the walking-associated cognitive task matters.

BACKGROUND: Changes in gait patterns due to a simultaneously performed cognitive task have been reported previously and associated with an increased falling risk among older adults. Little is known whether the type of cognitive task performed while walking is important concerning possible gait interference in older fall-prone individuals. OBJECTIVE: To quantify and compare the effects of two different cognitive tasks on gait in transitionally frail older adults. MEASUREMENTS: Gait was tested in 30 transitionally frail older adults (mean age 82.6 +/- 7.1 years, 90% female) while either walking alone, performing a simple arithmetic task, or performing a task of verbal fluency. Walking time in seconds, number of steps, frequency of lateral line stepping-over, and stops were recorded. Health status was assessed using standard instruments of geriatric assessment. The classification of Speechley and Tinetti was used to define the participants' degree of frailty. RESULTS: Walking time and number of steps increased significantly under both dual-task conditions compared to walking alone (p < 0.001) without reaching a significant difference between the two dual-task conditions (respectively, p = 0.131 and p = 0.407), whereas lateral gait instability (frequency of lateral line stepping-over) increased significantly in association with counting backward (p = 0.006) but not with the verbal fluency task (p = 1). CONCLUSION: Among the studied sample of transitional older adults, a walking- associated arithmetic task significantly interfered with lateral gait stability, whereas no lateral gait deviations were seen in association with a verbal fluency task. We, therefore, suggest that the choice of the attention-splitting task in dual-task gait assessment among older adults must be made carefully.

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