Balshaw et al 2021 MSSE HUMAN MUSCLE SIZE-STRENGTH RELATIONSHIP (for repository).pdf (1.41 MB)
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The human muscle size and strength relationship: effects of architecture, muscle force, and measurement location

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posted on 10.05.2021, 14:51 authored by Tom BalshawTom Balshaw, Tom Maden-Wilkinson, Garry J Massey, Jonathan FollandJonathan Folland
PURPOSE: This study aimed to determine the best muscle size index of muscle strength by establishing if incorporating muscle architecture measurements improved the human muscle size-strength relationship. The influence of calculating muscle force, and the location of anatomical cross-sectional area (ACSA) measurements on this relationship were also examined. METHODS: Fifty-two recreationally active males completed unilateral isometric knee extension strength assessments and MRI scans of the dominant thigh and knee to determine quadriceps femoris (QF) size variables (ACSA along the length of the femur, maximum ACSA [ACSAMAX] and volume [VOL]) and patellar tendon moment arm. Ultrasound images (2 sites per constituent muscle) were analyzed to quantify muscle architecture (fascicle length, pennation angle), and when combined with VOL (from MRI), facilitated calculation of QF effective PCSA (EFFPCSA) as potentially the best muscle size determinant of strength. Muscle force was calculated by dividing maximum voluntary torque (MVT) by the moment arm and addition of antagonist torque (derived from hamstring EMG). RESULTS: The associations of EFFPCSA (r=0.685), ACSAMAX (r=0.697), or VOL (r=0.773) with strength did not differ, although qualitatively VOL explained 59.8% of the variance in strength, ~11-13% greater than EFFPCSA or ACSAMAX. All muscle size variables had weaker associations with muscle force than MVT. The association of strength-ACSA at 65% of femur length (r=0.719) was greater than for ACSA measured between 10-55% and 75-90% (r=-0.042-0.633) of femur length. CONCLUSIONS: In conclusion, using contemporary methods to assess muscle architecture and calculate EFFPCSA did not enhance the muscle strength-size association. For understanding/monitoring muscle size, the major determinant of strength, these findings support the assessment of muscle volume, that is independent of architecture measurements, and was most highly correlated to strength.


Versus Arthritis Centre for Sport, Exercise, and Osteoarthritis (Grant reference 20194)



  • Sport, Exercise and Health Sciences

Published in

Medicine and Science in Sports and Exercise








Lippincott, Williams & Wilkins


AM (Accepted Manuscript)

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© American College of Sports Medicine

Publisher statement

This is a non-final version of an article published in final form in Medicine & Science in Sports & Exercise: October 2021 - Volume 53 - Issue 10 - p 2140-2151 doi: 10.1249/MSS.0000000000002691.

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Prof Jonathan Folland. Deposit date: 9 May 2021