Abstract
The aim of this study was to investigate the effect of aging and resistance training with a moderate load on the size and mechanical properties of the patellar (PT) and Achilles tendon (AT) and their associated aponeuroses; medial gastrocnemius (MG) and vastus lateralis (VL). Young (Y55; 24.8 ± 3.8 yrs, n = 11) and old men (O55; 70.0 ± 4.6 yrs, n = 13) were assigned to undergo a training program (12 weeks; 3 times/week) of moderate slow resistance training [55% of one repetition maximum (RM)] of the triceps surae and quadriceps muscles. Tendon dimensions were assessed using 1.5 T magnetic resonance imaging before and after 12 weeks. AT and PT cross sectional area (CSA) were determined every 10% of tendon length. Mechanical properties of the free AT, MG aponeurosis, PT, and VL aponeurosis were assessed using ultrasonography (deformation) and tendon force measurements. CSA of the AT but not PT was greater in O55 compared with Y55. At baseline, mechanical properties were generally lower in O55 than Y55 for AT, MG aponeurosis and VL aponeurosis (Young’s modulus) but not for PT. CSA of the AT and PT increased equally in both groups following training. Further, for a given force, stiffness and Young’s modulus also increased equally for VL aponeurosis and AT, for boths groups. The present study highlights that except for the PT, older men have lower tendon (AT, MG aponeurosis, and VL aponeurosis) mechanical properties than young men and 12-weeks of moderate slow resistance training appears sufficient to improve tendon size and mechanical adaptations in both young and older men. New and Noteworthy: These novel findings suggest that short-term moderate slow resistance training induces equal improvements in tendon size and mechanics regardless of age.
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Data availability
Data can be send to any colleague that would need it. They just have to contact me by email. Actually, the numerous data corresonding to the different tested population and the different training intensities are in numerous excel files. The experiment was also focused on the effect of training intensity with age and show for the first time that a moderate training intensity induce the exact same effects on muscle and tendon adaptations as a high trining intensity with aging. These data will be submitted in another journal as EJAP rejected these data. Thus all these numerous data are in our excel files at the moments.
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The authors are grateful to all voluntaries who kindly participated in this study and to MRI technicians who made it possible to carry out the acquisition sessions. The study was funded by the research department of the regional council of Picardie (Amiens, France, reference funding number: TAGE2014), the French Ministère de l’Enseignement Supérieur et de la Recherche (MESER), Bispebjerg Hôpital (Denmark), and University of Copenhagen (Centre fo Healthy aging, Denmark). The funding body has no role in the collection, analysis, and interpretation of data or in the writing of the paper.
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AJL: acquisition, analysis, interpretation of data, draft of the paper, final approval of the version to be published, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. RBS: conception and design of the work, analysis, or interpretation of data for the work, review of the paper, final approval of the version to be published, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. FM: acquisition of data for the work, review of the paper, final approval of the version to be published, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. FC: acquisition of data for the work, review of the paper, final approval of the version to be published, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. FM: conception and design of the work, interpretation of data for the work, review of the paper, final approval of the version to be published, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. QD: acquisition and analysis of data for the work, review of the paper, final approval of the version to be published, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. SPM: conception and design of the work, interpretation of data for the work, review of the paper, final approval of the version to be published, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. CC: conception and design of the work, interpretation of data for the work, review of the paper, final approval of the version to be published, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. JFG: conception and design of the work, acquisition, analysis, and interpretation of data for the work, review of the paper, final approval of the version to be published, agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.
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Létocart, A.J., Svensson, R.B., Mabesoone, F. et al. Structure and function of Achilles and patellar tendons following moderate slow resistance training in young and old men. Eur J Appl Physiol (2024). https://doi.org/10.1007/s00421-024-05461-y
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DOI: https://doi.org/10.1007/s00421-024-05461-y