Increased sleep fragmentation, attributed to a decline in the amplitude of sleep-wake cycle (SWC) that seems to be linked to ageing, has been described as the most important factor for impaired sleep quality in the elderly. In this work we assessed possible between SWC circadian amplitude and; a-increasing age; and b-subjective sleep quality. Twenty five healthy and active subjects (aged from 60 to 83) completed sleep logs for 23 consecutive days in April 1989. Twenty two of them were also evaluated concerning subjective sleep quality. Data thus obtained were submitted to spectral analysis (to assess the strength of rhythmic components of SWC) and descriptive statistics. Significant correlations were evaluated using Spearman's rank correlation test. Results showed no significant correlation between subjects' ages and the strength of the circadian and the semicircadian components of SWC. 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