Submission Date


Document Type

Paper- Restricted to Campus Access


Health & Exercise Physiology

Faculty Mentor

Stephen Kolwicz Jr.

Student Contributor

Jack Thompson

Second Student Contributor

Paige Ponzo


Presented during the 25th Annual Summer Fellows Symposium, July 21, 2023 at Ursinus College.

Project Description

Running is considered one of the most popular forms of exercise worldwide with 7.9-13.3% of adults participating. Popularity in distance running has grown since 2020 with runners increasing weekly mileage by approximately 3 kilometers or 1.8 miles. Running is associated with numerous benefits, but also increases the risk of anemia due to repeated pounding of the foot which may decrease red blood cell mass by intravascular hemolysis. Female endurance athletes are especially at risk with nearly half experiencing exercise-induced or iron-deficiency anemia which is often attributed to menstruation. We explored sex differences in physical activity and hemoglobin levels in mice. Male and female were randomly assigned to a sedentary control (n=23) or voluntary wheel running (VWR, n=26) group. Mice in the VWR group were housed in a cage with unlimited access to a running wheel. Distances were tracked as revolutions on 30-minute intervals through a data acquisition software for a total of 6 weeks. Both control and VWR mice were fed a chow diet (58% carbohydrates, 13% fat, 29% protein). Body weights were tracked weekly, and after the 6-week training period concluded mice were given a 48-hour recovery period before organs (spleen, heart, liver, soleus, quadriceps) were harvested, weighed, and frozen for mitochondrial respiratory chain enzymatic activity assays and other tissue analysis. Whole blood and serum were extracted at time of harvest for hemoglobin assays. The findings of the study will provide greater insight into sex differences associated with physical activity and the effects on hemoglobin levels.


Available to Ursinus community only.