Effect of a physical activity programme in the aquatic environment on haemodynamic constants in pregnant women.

OBJECTIVE: To evaluate the effect of a physical activity programme in the aquatic environment with immersion up to the neck, of six weeks duration, on haemodynamic constants in pregnant women.

METHODS: A six-week physical activity programme in the aquatic environment was carried out with a total of 46 pregnant women, who were distributed into an experimental group (n = 18), which participated in the programme, and a control group (n = 28), which followed routine care. In both groups different haemodynamic measurements were evaluated before and after the program.

RESULTS: At the beginning of the programme the mean systolic blood pressure was similar between groups, but diastolic blood pressure was slightly higher in the experimental group. When the measurements at the last session were compared, arterial pressures (systolic, diastolic and mean) were significantly higher in the control group (p <.050). Similarly, the initial plasma volume values did not differ between groups, but after the intervention, the control group women showed a higher mean (p <.010). The fraction of sodium excretion (FENa) increased significantly in the experimental group, after the programme, with a mean three times higher (p <.050). Aldosterone plasma levels did not show significant differences between the groups in the different measurements.

CONCLUSION: A programme of swimming and immersion exercises in pregnant women contributes to hydrosaline balance, preventing an excessive increase in usual plasma volume during pregnancy and in the activity of the renin-aldosterone axis.