A1 Journal article (refereed)
High Responders to Hypertrophic Strength Training Also Tend to Lose More Muscle Mass and Strength During Detraining Than Low Responders (2021)

Räntilä, A., Ahtiainen, J. P., Avela, J., Restuccia, J., Kidgell, D., & Häkkinen, K. (2021). High Responders to Hypertrophic Strength Training Also Tend to Lose More Muscle Mass and Strength During Detraining Than Low Responders. Journal of Strength and Conditioning Research, 35(6), 1500-1511. https://doi.org/10.1519/jsc.0000000000004044

JYU authors or editors

Publication details

All authors or editors: Räntilä, Aapo; Ahtiainen, Juha P.; Avela, Janne; Restuccia, Joel; Kidgell, Dawson; Häkkinen, Keijo

Journal or series: Journal of Strength and Conditioning Research

ISSN: 1064-8011

eISSN: 1533-4287

Publication year: 2021

Publication date: 05/04/2021

Volume: 35

Issue number: 6

Pages range: 1500-1511

Publisher: Lippincott Williams & Wilkins

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1519/jsc.0000000000004044

Publication open access: Not open

Publication channel open access: Channel is not openly available

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/80002


This study investigated differences in individual responses to muscle hypertrophy during strength training and detraining. Ten weeks of resistance training was followed by 6 weeks of detraining in men (n 5 24). Bilateral leg press (LP) one-repetition maximum (1RM) and maximal electromyography (EMGs) of vastus lateralis (VL) and vastus medialis, maximal voluntary activation (VA), transcranial magnetic stimulation for corticospinal excitability (CE), cross-sectional area of VL (VLCSA), selected serum hormone concentrations were measured before and repeatedly during training and detraining. In the total group, VLCSA increased by 10.7% (p 5 0.025) and LP 1RM by 16.3% (p , 0.0001) after training. The subjects were split into 3 groups according to increases in VLCSA: high responders (HR) . 15% (n 5 10), medium responders (MR) 15–4.5% (n 5 7), and low responders (LR) , 4.5% (n 5 7). Vastus lateralis CSA in HR and MR increased statistically significantly from pre to posttraining but not in LR. Only HR increased LP 1RM statistically significantly from pre to post. Maximal EMG activity increased 21.3 6 22.9% from pre- to posttraining for the total group (p 5 0.009) and for MR (p , 0.001). No significant changes occurred in VA and CE or serum hormone concentrations. During detraining, HR showed a decrease of 210.5% in VLCSA, whereas MR and LR did not. None of the subgroups decreased maximal strength during the first 3 weeks of detraining, whereas HR showed a slight (by 2.5%) rebound in strength. The present results suggest that strength gains and muscle activation adaptations may take place faster in HR and decrease also faster compared with other subgroups during detraining.

Keywords: strength training; training response; muscle mass; muscle strength

Free keywords: strength training; hypertrophy; high and low responders; detraining

Contributing organizations

Ministry reporting: Yes

Reporting Year: 2021

JUFO rating: 1

Last updated on 2022-20-09 at 13:47