How Endurance Exercise Affects Your Heart, Muscles, and Kidneys: Insights from 2025 Biomedical Research

Sports Formula
Dec 24, 2025
2 min read

Long-distance running and other endurance sports are widely praised for their health benefits, but what happens inside the body during and after prolonged aerobic exercise?

A 2025 biomedical study provides one of the most detailed analyses of how cardiac, muscle, and kidney biomarkers respond to endurance activity, especially in trained individuals with obesity. (pubmed.ncbi.nlm.nih.gov)

🧬 The Study in a Nutshell

Researchers recruited 17 trained men with obesity to participate in half-marathons, 30 km races, or full marathons. Biomarkers were measured at three points:

Before exercise
Immediately after
72 hours post-exercise

They analyzed:

Cardiac markers: troponin I, CK-MB
Muscle damage markers: myoglobin, LDH
Kidney function markers: creatinine, eGFR

❤️ What Happens to Your Heart

Cardiac biomarkers like troponin I increased after long-distance running.
This indicates temporary cardiac stress, even in trained athletes.
The good news: levels usually return to normal within a few days.

Takeaway: Endurance exercise is safe for healthy hearts but triggers short-term cardiac strain that the body adapts to over time.

🦵 Muscle Response

Biomarkers such as myoglobin and LDH rose significantly, reflecting micro-injuries in skeletal muscles.
This is a normal response to prolonged exertion and part of muscle remodeling and adaptation.

Tip: Proper recovery and nutrition are key to muscle repair after long runs.

🩺 Kidney Impact

Kidney function showed temporary changes: eGFR decreased right after the race.
Most markers returned to baseline within 72 hours, but transient stress on the kidneys was observed.

Implication: Hydration and gradual progression in training are essential, especially for individuals with higher risk of kidney or metabolic issues.

🧠 Clinical Takeaways

Exercise is medicine—but dose matters: The intensity and duration of activity influence how much stress your heart, muscles, and kidneys experience.
Monitoring recovery is important: Even healthy adults benefit from paying attention to sleep, nutrition, and gradual progression.
Personalized programs work best: Especially for overweight or obese individuals, tailored training helps maximize benefits while minimizing risk.

📊 Why This Research Matters

This study is a biomedical milestone because it:

Tracks multiple organ systems simultaneously during real-world endurance exercise.
Provides guidance for safe exercise prescription in populations with metabolic risk factors.
Helps coaches, clinicians, and fitness enthusiasts understand how long-distance aerobic exercise affects the body at the biomolecular level.

🔹 Reference

D’Alleva M, Sanz JM, Giovanelli N, et al. The influence of prolonged aerobic exercise on cardiac, muscular, and renal biomarkers in trained individuals with obesity. European Journal of Applied Physiology, 125(5):1485–1500, 2025. (pubmed.ncbi.nlm.nih.gov)

🔹 Key Takeaway

Endurance exercise is beneficial but stresses the heart, muscles, and kidneys temporarily. Knowing how your body responds at the biomarker level can help you train smarter, recover faster, and stay healthier.