Consequences of the modulation of gestational resistance training intensity for placental cell composition and nutrient transporter expression.

Introduction: Resistance training during pregnancy provides benefits for the mother and fetus, but little is known about the effects of resistance training on placental structure and function or the repercussions of modifying resistance training intensity on the mother-fetus-placenta triad.

Methods: Female Wistar rats were submitted to resistance training involving a ladder climb (80 % of maximum load carried (MLC), 5-day/week for 3-weeks) before pregnancy. After confirmation of mating, the rats were randomly divided into three groups, according to resistance training intensity during pregnancy: constant-intensity training (CIT, trained at 80 % of MLC through gestation), decreasing-intensity training (DIT, 80 % of MLC during first and second weeks of gestation and 50 % of MLC in the third week), and undulating-intensity training (UIT, 50 % of MLC in the first and third weeks, and 80 % of MLC in the second week).