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Updated: Jan 31, 2026

Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading

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Published on: March 6, 2014

Internal and External Training Load: 15 Years On.

Franco M Impellizzeri, Samuele M Marcora, Aaron J Coutts

International Journal of Sports Physiology and Performance

|January 8, 2019

Summary

This summary is machine-generated.

Understanding exercise and athlete stress requires precise training load management. This commentary refines the concepts of internal and external training load for better scientific application and athlete adaptation.

Keywords:

exercise training psychobiological response stimulus stressor workload

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Area of Science:

Sports Science
Exercise Physiology
Human Adaptation

Background:

Exercise acts as a physiological stressor, triggering adaptations across organ systems.
Optimizing athletic performance necessitates individualized stress management through training load control.
A theoretical framework for training load (internal and external) was proposed in 2003.

Purpose of the Study:

To extend and clarify the theoretical framework of training load.
To refine the definitions of internal and external training load.
To prevent misinterpretation of training load concepts in sports science.

Main Methods:

Conceptual analysis and theoretical extension.
Review and refinement of existing definitions.
Discussion of measurable constructs in the training process.

Main Results:

Proposed enhancements to the existing training load framework.
Clarified definitions for internal and external training load.
Provided a foundation for more precise training load quantification.

Conclusions:

Refined definitions improve the understanding and application of training load.
Accurate training load management is crucial for maximizing athlete adaptation.
Further clarification prevents misinterpretation and enhances scientific rigor.