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Related Experiment Video

Updated: May 18, 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

Maximal strength training and increased work efficiency: contribution from the trained muscle bed.

Zachary Barrett-O'Keefe¹, Jan Helgerud, Peter D Wagner

¹Department of Exercise and Sport Science, University of Utah, Salt Lake City, UT 84148, USA.

Journal of Applied Physiology (Bethesda, Md. : 1985)

|September 18, 2012

Summary

Maximal strength training improves exercise efficiency by reducing oxygen uptake in trained muscles. This adaptation lowers muscle blood flow but does not change the arterial-venous oxygen difference.

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Area of Science:

Exercise Physiology
Skeletal Muscle Physiology
Metabolic Adaptations

Background:

Maximal strength training (MST) is known to enhance exercise efficiency, indicated by reduced pulmonary oxygen uptake (Vo(2)) at a given workload.
However, the precise origin of this increased efficiency within trained skeletal muscle and its impact on local muscle hemodynamics and oxygen extraction remain unclear.

Purpose of the Study:

To investigate whether MST-induced improvements in exercise efficiency originate in skeletal muscle.
To determine the effect of MST on single-leg muscle blood flow and arterial-venous oxygen difference (a-vO(2diff)) during submaximal exercise.

Main Methods:

Five trained subjects completed an 8-week MST program focusing on the rate of force development.
Pre- and post-training assessments included pulmonary Vo(2) via indirect calorimetry, single-leg blood flow using thermodilution, and single-leg a-vO(2diff) via blood gas analysis during submaximal cycling.

Main Results:

MST did not alter peak pulmonary Vo(2) or peak work rate.
Following MST, pulmonary Vo(2) during submaximal cycling (237 W) was significantly reduced.
This reduction was associated with decreased single-leg Vo(2) and single-leg blood flow, but no significant change in single-leg a-vO(2diff).

Conclusions:

The enhanced exercise efficiency following MST is attributable to adaptations within skeletal muscle.
MST reduces the metabolic demand of trained muscle, leading to decreased muscle blood flow.
Muscle oxygen extraction, as reflected by a-vO(2diff), is not altered by MST-induced efficiency gains.