Background and Objective: Abnormal regulation of apoptosis and metallothioneine in maternal tissues may be dangerous for the developing fetus. The aim of this study was to investigate the effect of endurance swimming training on liver apoptotic index and metallothioneine concentration in pregnant rats.

Materials and Methods: Sixteen pregnant Wistar rats (200 ± 20 g) were divided into two groups: control (Cnt) and swimming training (ST). Pregnant rats in ST group were forced to swimming in a specific pool from first day of pregnancy until delivery. The time of training in first day of pregnancy was 30 min and this time in second week reached to 60 min by increasing of 5 min per day. This time (60 min) continued to the end of third week. Liver tissue was collected two days after delivery. The liver apoptotic index and MT concentration were determined with TUNEL and ELISA methods, respectively. Independent sample t-test was applied for statistical analysis of the data (p < 0.05).

Results: Endurance swimming training did not cause significant changes in liver MT levels in pregnant rats (p=0.509). No significant changes were observed in liver apoptotic index between the groups (p=0.424). Morphological characteristics of hepatocytes showed no changes during training program as compared to control group.

Conclusion: Sub-maximal endurance swimming training during pregnancy can be used to gain the benefits of exercise during pregnancy without induction of maternal liver apoptosis or changes in MT concentration