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Related Experiment Video

Updated: Jun 24, 2026

Improving Strength, Power, Muscle Aerobic Capacity, and Glucose Tolerance through Short-term Progressive Strength Training Among Elderly People

Improving Strength, Power, Muscle Aerobic Capacity, and Glucose Tolerance through Short-term Progressive Strength Training Among Elderly People

Published on: July 5, 2017

Muscle efficiency improves over time in world-class cyclists.

Alfredo Santalla¹, José Naranjo, Nicolás Terrados

¹Departamento de Deportes e Informática (despacho 11.1.30), Pablo de Olavide University, Seville, Spain. asanher@upo.es

Medicine and Science in Sports and Exercise

|April 7, 2009

Summary

Professional cyclists improved muscular efficiency (delta efficiency) over five seasons without significant changes in maximal oxygen uptake. This enhanced efficiency may compensate for lower VO2max, aiding performance.

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Area of Science:

Sports Science
Exercise Physiology
Biomechanics

Background:

Elite cyclists undergo rigorous training and competition.
Muscular efficiency is a key factor in endurance performance.
Longitudinal studies on physiological adaptations in professional athletes are crucial.

Purpose of the Study:

To quantify changes in muscular efficiency in professional cyclists over a five-season period.
To investigate the relationship between muscular efficiency and maximal oxygen uptake (VO2max) in elite cyclists.
To explore the role of improved delta efficiency in performance compensation.

Main Methods:

Twelve world-class male professional road cyclists were studied.
Incremental cycling tests were performed before and after a five-season training/competition period.
Delta efficiency (DE) was calculated based on workload and oxygen consumption.

Main Results:

Delta efficiency significantly increased from 23.6% to 27.0% over five seasons (P < 0.01).
Maximal oxygen uptake (VO2max) did not show significant changes.
A significant inverse correlation was observed between DE and VO2max in the fifth season.

Conclusions:

Professional cyclists demonstrate increased delta efficiency with prolonged training and competition.
Enhanced delta efficiency may serve as a compensatory mechanism for performance, particularly in athletes with lower VO2max.
The findings highlight the adaptive capacity of muscular efficiency in elite endurance athletes.