The purpose of the present study was to identify changes in different components of physical capacity among middle-aged women and men employed in the municipal branch for 16 years. The data were obtained by laboratory measurements and postal questionnaires. The study group consisted of 45 middle-aged subjects, who were on average 51.5 years old at the beginning of the follow-up in 1981 and 67.3 years in 1997. During the 16-year follow-up period, the average physical capacity of these workers decreased by approximately 20%. The study showed that the greatest changes occurred in isometric trunk muscle strength and in the flexibility of the spine, whereas smaller changes were noted in anthropometrics. The decrease of physical capacity was greater among men (range 11.6% to 33.7%) than among women (range 3.3% to 26.7%), although women had more individual variations. On average, people without disease or who were physically active displayed better physical capacity than people with disease or who were physically passive.