Physiological Changes, Activity, and Stress During a 100-km-24-h Walking-March

Area of Science:

• Exercise Physiology
• Sports Medicine
• Human Metabolism

Background:

• Long-endurance exercises induce metabolic and physiological changes.
• Limited research exists on very long-duration, low-intensity exercise in healthy individuals.

Purpose of the Study:

• To evaluate changes in body composition and metabolism during low-intensity, long-endurance events.

Main Methods:

• Recruited 43 healthy recreational athletes (25 male, 18 female) for the "100 km Mammutmarsch" hiking event.
• Measured body composition (BIA) pre- and post-event; analyzed serum markers (NT-pro-BNP, CRP, lipids, CK, etc.) at various stages.
• Utilized actimeters and heart rate monitors to assess exercise intensity (METs) and heart rate; compared finishers vs. non-finishers.

Main Results:

• Significant elevations in muscle/cardiac stress markers (CRP, CK, cortisol, NT-pro-BNP) and decreases in lipid metabolism markers (cholesterol, LDL).
• Physiological alterations were comparable to high-intensity exercise, with NT-pro-BNP increasing fourfold and LDL decreasing by 20%.
• Exercise duration, age, BMI, training status, and sex influenced stress marker elevation; NT-pro-BNP may indicate cardiovascular fitness.

Conclusions:

• Low-intensity, long-endurance walking triggers substantial systemic stress and favorable lipid profile shifts, similar to higher-intensity events.
• No cardiac cell damage was observed despite increased cardiac stress parameters.
• Exercise duration appears to be a more significant factor than intensity for stress markers and metabolism.