RESUMO
To quantify changes in leisure time physical activity (LTPA) type, frequency, duration and intensity during the first half of pregnancy as compared with the year prior to pregnancy. A cross sectional study was conducted at the Maternal University Hospital in Granada, Spain. A total of 1,175 healthy pregnant women attending a scheduled visit during the 20-22nd gestational week were enrolled in the study. Information about socio-demographic, obstetric and life-style variables during the previous year and the first half of pregnancy were collected. LTPA was quantified by assigning metabolic equivalents to each activity according to frequency, intensity and duration. The prevalence of women who met the optimal physical activity recommendations before and during pregnancy was calculated, and the McNemar-Bowker symmetry test was used to assess changes in type, frequency, intensity and duration of activities between the two periods. Some sort of LTPA was performed before and during pregnancy by 68.6% of the pregnant women. Respectively, just 27.5% and 19.4% of women fulfilled LTPA recommendations prior to pregnancy and during pregnancy; 12.6% of the women meeting recommendations prior to pregnancy later did not meet those recommendations during gestation, and 4.5% showed the reverse trend. A light increase in walking as a LTPA, and a decrease in the rest of the LTPA type activities, were seen during pregnancy. Some 13.4% of women changed from moderate--the year before- to light LTPA- during pregnancy. Pregnancy involved a decrease in LTPA, not only regarding frequency, but also duration and intensity.