This clinical trial aims to compare the immediate tissue response in postpartum women with and without rectus abdominis diastasis (RAD) after undergoing radiofrequency diathermy (RFD) treatment. The main question it seeks to answer is: Do postpartum women with and without RAD exhibit different acute tissue responses in terms of pressure pain threshold, superficial thermal sensitivity, and tissue elasticity? To determine whether there are differences in these acute tissue responses between the groups, researchers will compare RFD with a sham RFD intervention in postpartum women with and without RAD.

Participants will receive one session of either RFD or a sham RFD intervention and will complete three assessments: one at baseline and two after the intervention, one immediately afterwards and one 20 minutes afterwards.

A randomised controlled experimental study will be conducted. The sample will consist of 48 postpartum women: 24 who have been diagnosed with pathological RAD and 24 who have not. The participants will be randomly assigned to one of two groups: (i) a radiofrequency diathermy (RFD) group (n = 12), and (ii) a sham RFD group (n = 12). All participants will receive a single treatment session. Evaluations will be performed at three time points: baseline, immediately after the intervention and 20 minutes post-intervention. The variables assessed will include pressure pain threshold, superficial thermal sensitivity and tissue elasticity.

Inclusion Criteria:

• Age between 20 and 45 years old.
• BMI between 18.5 and 29.9 kg/mw.
• Postpartum period between 6 months and 1 year Additionally, in the group of women with RAD, pathological RAD will be defined as an inter-rectus distance greater than 2.2 cm (measured 3 cm above the navel), according to the criteria of Beer et al. (2009)

Exclusion Criteria:

• Previous surgeries involving the abdominal wall.
• Cesarean deliveries.
• Women diagnosed with chronic pain