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Related Experiment Video

Updated: Jun 21, 2026

Imaging Approaches to Assessments of Toxicological Oxidative Stress Using Genetically-encoded Fluorogenic Sensors

Imaging Approaches to Assessments of Toxicological Oxidative Stress Using Genetically-encoded Fluorogenic Sensors

Published on: February 7, 2018

Commentary: oxidative stress reconsidered.

Regina Brigelius-Flohé¹

¹German Institute of Human Nutrition Potsdam-Rehbruecke, 14558, Nuthetal, Germany, flohe@dife.de.

Genes & Nutrition

|July 18, 2009

Summary

Reactive oxygen species (ROS) are essential for healthy life, not just damaging. Moderate ROS levels during exercise aid muscle function and adaptation, while antioxidants may hinder this process.

Area of Science:

Physiology
Cell Biology
Exercise Science

Background:

Traditionally, oxidants and reactive oxygen species (ROS) are viewed as solely damaging.
Emerging evidence suggests ROS play crucial physiological roles in maintaining health.
A paradigm shift is occurring regarding the dual nature of ROS.

Purpose of the Study:

To discuss the changing understanding of reactive oxygen species (ROS) and antioxidants.
To explore the beneficial roles of ROS in physiological processes.
To highlight the impact of exercise on ROS and adaptation.

Main Methods:

Symposium discussion involving experts in nutrition, oxygen biology, and medicine.
Review of current evidence on the physiological functions of ROS.

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Focus on exercise as a model for understanding beneficial oxidant effects.

Main Results:

Low to moderate concentrations of ROS produced during exercise are beneficial.
ROS are necessary for skeletal muscle force production and training adaptation.
Antioxidant supplementation during training can impede adaptation and endogenous defense induction.

Conclusions:

Reactive oxygen species (ROS) have essential physiological functions beyond toxicity.
Exercise-induced ROS are critical for muscle adaptation and performance.
Further research is needed to fully elucidate the conditions under which ROS are beneficial or detrimental.