Acute Response of Heart Rate Variability to Hydrotherapy in Pregnant Women in the Second and Third Trimesters

• Grant number: 25/06698-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2025
• End date: June 30, 2026
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Mikaela da Silva Corrêa
• Grantee: Maria Clara de Brito Rauli
• Host Institution: Faculdade de Filosofia e Ciências (FFC). Universidade Estadual Paulista (UNESP). Campus de Marília. Marília , SP, Brazil

Abstract

Pregnancy induces profound changes in the cardiovascular system. The autonomic nervous system, with reduced parasympathetic activity, results in lower heart rate variability (HRV). Although physical exercise can increase HRV and improve autonomic control, the results in pregnant women remain controversial. Hydrotherapy offers specific benefits during pregnancy, but its effects on HRV still require further investigation.Objective: To evaluate the acute effects of hydrotherapy on the heart rate variability of pregnant women in different trimesters.Methodology: Pregnant women from the 13th gestational week, classified as low-risk and over 18 years old, will be recruited through social media advertisements. Participants who sign the Informed Consent Form will undergo anamnesis, a six-minute walk test (6MWT), and heart rate and R-R interval measurements using a heart rate monitor after active postural change (10 minutes in the left lateral decubitus position and 10 minutes standing), initially. Additionally, a 10-minute resting R-R interval signal will be collected before and after a hydrotherapy session.Data Analysis: After assessing data normality and homogeneity, appropriate statistical tests will be used to compare HRV indices before and after hydrotherapy, compare HRV responses to exercise with responses to active postural change, and compare HRV indices and 6MWT distance across gestational trimesters. A significance level of 5% will be adopted.