# Effects of Ladder-Climbing Exercise on Mammary Cancer: Data from a Chemically Induced Rat Model

## TL;DR

This study investigates how resistance training affects mammary cancer in rats, finding that while tumors appeared slightly earlier, they were less aggressive and mortality was lower.

## Contribution

The study introduces evidence that resistance training may reduce tumor aggressiveness and mortality in chemically induced mammary cancer in rats.

## Key findings

- Tumors appeared earlier in exercising rats but were less aggressive.
- Mortality rates were lower in the exercising group compared to the control group.
- No harmful systemic inflammation was observed in exercising rats.

## Abstract

Breast cancer is a major health concern for both humans and companion animals, particularly female dogs and cats. This study explores whether resistance training can influence the development of mammary cancer in female rats. The rats were divided into four groups, including those that exercised by climbing a ladder with increasing weight three times a week for 18 weeks. At the end of the study, tumor development, inflammation, and overall health were assessed. While tumors appeared slightly earlier and in more animals that exercised, these tumors were less aggressive, and the mortality rate was lower. Importantly, no signs of harmful systemic inflammation were found. Exercise is known to support health by improving fitness, strengthening immunity, and enhancing metabolism. These findings suggest that resistance training may have potential benefits in managing mammary cancer in pets. However, more research is needed to confirm how exercise can be safely and effectively used in veterinary medicine.

Breast cancer remains a significant global health issue, affecting both humans and companion animals, particularly female dogs and cats, where mammary tumors are among the most common cancers. Strategies to minimize the impact of this disease on patients, pet owners, and veterinary medicine are essential. This study analyses the effects of resistance training on the development of chemically induced mammary cancer in female Wistar rats, divided into four groups: sedentary control (CTR), sedentary induced (CTR+N-methyl-N-nitrosourea (MNU)), exercised control (EX), and exercised induced (EX+MNU). The exercise protocol involved ladder climbing three times a week for 18 weeks with the load progressively increasing. At the study’s end, blood and histopathological samples were collected and analyzed. Although tumor onset occurred two weeks earlier and incidence was slightly higher in the exercised group (EX+MNU) compared to the control group (CTR+MNU), the mortality rate was lower, and the malignancy was not as aggressive. No systemic inflammation was observed, as the levels of albumin, C-reactive protein (CRP), and interleukin 6 (IL-6) in the MNU groups remained similar to the controls. Exercise has been shown to promote overall health by increasing physical fitness, boosting immunological function, and improving metabolic health. These findings may offer valuable insights into the potential role of resistance training in managing mammary cancer in companion animals. However, further research is required to assess clinical applicability and to establish safe and effective exercise protocols for veterinary oncology.