Write a structured abstract for the given article. 
Background:
Physical activity is an important element of a healthy lifestyle. In general, the total amount of physical activity, as well as the diversity in types of activity, declines with age. In the Netherlands in 2000, 59% of people aged 65 and over were not engaged in sufficient physical activity to obtain health benefits, i.e. at least 30 minutes of moderate intensity activity on five days a week [1,2]. Another possible benefit of exercise programs or enhancement in habitual physical activity may be a decline in complaints of constipation. Underlying mechanisms regarding the association between physical exercise and constipation are unclear but a favourable effect on colonic motility, decreased blood flow to the gut, biomechanical bouncing of the gut during running, compression of the colon by abdominal musculature, and increased fibre intake as a result of increased energy expenditure have all been reported [7]. Constipation is a common complaint in older people, and many people become gradually more constipated with age [8]. One of the contributing factors may be decreased mobility and physical inactivity.

Methods:
Study design:
We conducted a 6-months randomized controlled trial of three different moderate-intensity training protocols among older adults living in long-term care facilities, i.e. homes for the aged, with services ranging from independent living to skilled nursing. In this report we describe the effects on habitual physical activity and constipation, which were secondary outcome measures. Effects on the primary outcomes i.e. physical function and wellbeing are described elsewhere [11,12].
Study population:
Participants of the study were living in six residential and extended care facilities in the North-Western part of The Netherlands (i.e. West-Friesland). Informative meetings were organized in each home so that the design of the study and the interventions could be explained in detail. Information regarding the study was also available in brochures for the people to take home. At the end of the meeting, subjects received a form on which they could indicate whether they were interested in the study.


Results:
In total, 224 subjects were enrolled in the study and randomly assigned to the four intervention groups. Mean age of these subjects was 81.7, ranging from 64 to 94 yr. For 157 subjects (70%) complete data were available from the physical activity questionnaire. Mainly due to technical problems, complete accelerometer data were availa Make sure your entire response is wrapped in JSON format.
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