The relationship between lower body strength and obstructed gait in community-dwelling older adults

OBJECTIVES: To determine the relationship between lower body strength of community-dwelling older adults and the time to negotiate obstructed gait tasks.

DESIGN: A correlational study.

SETTING: The Biomechanics Laboratory, Deakin University, Australia.

PARTICIPANTS: Twenty-nine women and 16 men aged 62 to 88 were recruited using advertisements placed in local newspapers. The participants were independent community dwellers, healthy and functionally mobile.

MEASUREMENTS: Maximal isometric strength of the knee extensors and dynamic strength of the hip extensors, hip flexors, hip adductors, hip abductors, knee extensors, knee flexors, and ankle plantar flexors were assessed. The times to negotiate four obstructed gait tasks at three progressively challenging levels on an obstacle course and to complete the course were recorded. The relationship between strength and the crossing times was explored using linear regression models.

RESULTS: Significant associations between the seven strength measures and the times to negotiate each gait task and to walk the entire course at each level were obtained (r = -0.38 to -0.55; P < .05). In addition, the percentage of the variance explained by strength (R2), consistently increased as a function of the progressively challenging level. This increase was particularly marked for the stepping over task (R2 = 19.3%,25.0%, and 27.2%, for levels 1, 2, and 3, respectively) and the raised surface condition (R2 = 17.1%,21.1%, and 30.8%, for levels 1,2, and 3, respectively) .

CONCLUSION: The findings of the study showed that strength is a critical requirement for obstructed locomotion. That the magnitude of the association increased as a function of the challenging levels suggests that intervention programs aimed at improving strength would potentially be effective in helping community-dwelling older adults negotiate environmental gait challenges.

Constipation and diet in a community sample of older Australians

Objective: To estimate the prevalence of constipation and laxative use in a sample of people 65 years and over and examine relationships between usual diet and constipation.
Design: A mailed survey using validated instruments to measure bowel habit and laxative use with follow-up interviews to collect dietary data.
Subjects and setting: Three hundred and thirty people aged 65 years and over living at home in Melbourne were randomly selected from the electoral roll of a federal electorate.
Statistical analysis: Descriptive statistics, frequencies and two sample t-tests were used.
Results: Seventy-nine people responded to the mailed bowel survey and 61 were interviewed to collect food intake data. The proportion of constipated people was approximately one quarter (n = 18). Laxative use in the previous 12 months was reported by a fifth of respondents and in these subjects one in four was not constipated. Analysis of the dietary data revealed that the average number of cereal and vegetable serves consumed per day was similar to the national average but less than recommended by nutrition bodies although fruit intake met these recommendations. Constipated subjects consumed fewer serves from the cereals food group than those who were not constipated (2.9 and 3.5 serves respectively, P = 0.03).
Conclusion: Constipation and laxative use appears to be as common in older Australians as in similar populations overseas. Low intake of cereal foods may be a contributing factor.

Motor-unit Coherence During Isometric Contractions Is Greater in a Hand Muscle of Older Adults

The purpose of this study was to quantify the strength of motor-unit coherence from the first dorsal interosseus muscle in young and old adults using data obtained in a previous study, where no differences in motor-unit synchronization between the two groups were observed.

The Effects of Progressive Resistance Training on Obstructed-Gait Tasks in Community-Living Older Adults

This study examined the effects of improved strength on an obstacle course (OC) simulating gait tasks commonly encountered by community-living older adults. Forty-five adults (mean age 68.2 +/- 1.5 years) were randomly assigned to a control (10 women, 5 men) or an experimental group (EXP; 19 women, 10 men) and trained 3 days/week for 12 weeks.