TY - JOUR
T1 - American Society of Biomechanics Journal of Biomechanics Award 2017
T2 - High-acceleration training during growth increases optimal muscle fascicle lengths in an avian bipedal model
AU - Salzano, M. Q.
AU - Cox, S. M.
AU - Piazza, S. J.
AU - Rubenson, J.
N1 - Funding Information:
We would like to thank Justin Csaszar, Josh Remillard, Leighann Warholak, Paige Reynolds, Melissa Minniti, Jillian Butkiewicz, Sina Pooresmaeil, Stephen Blakely, Brandon Stone, and Tyler Faimon for their help with the training, dissections, and movement scores. We would also like to thank Emily Southmayd and Melissa Welker for performing the DXA and X-ray scans, respectively. Finally, we would like to thank the staff of the Penn State Animal Resource Program for the care of our animals during the study., Research reported in this publication was supported in part through a seed grant from the Center for Human Evolution and Diversity, Penn State University and The National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health under award number R21AR071588. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health., The authors declare no conflicts of interest.
Funding Information:
Research reported in this publication was supported in part through a seed grant from the Center for Human Evolution and Diversity, Penn State University and The National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health under award number R21AR071588. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
Publisher Copyright:
© 2018 Elsevier Ltd
PY - 2018/10/26
Y1 - 2018/10/26
N2 - Sprinters have been found to possess longer muscle fascicles than non-sprinters, which is thought to be beneficial for high-acceleration movements based on muscle force-length-velocity properties. However, it is unknown if their morphology is a result of genetics or training during growth. To explore the influence of training during growth, thirty guinea fowl (Numida meleagris) were split into exercise and sedentary groups. Exercise birds were housed in a large pen and underwent high-acceleration training during their growth period (age 4–14 weeks), while sedentary birds were housed in small pens to restrict movement. Morphological analyses (muscle mass, PCSA, optimal fascicle length, pennation angle) of a hip extensor muscle (ILPO) and plantarflexor muscle (LG), which differ in architecture and function during running, were performed post-mortem. Muscle mass for both ILPO and LG was not different between the two groups. Exercise birds were found to have ∼12% and ∼14% longer optimal fascicle lengths in ILPO and LG, respectively, than the sedentary group despite having ∼3% shorter limbs. From this study we can conclude that optimal fascicle lengths can increase as a result of high-acceleration training during growth. This increase in optimal fascicle length appears to occur irrespective of muscle architecture and in the absence of a change in muscle mass. Our findings suggest high-acceleration training during growth results in muscles that prioritize adaptations for lower strain and shortening velocity over isometric strength. Thus, the adaptations observed suggest these muscles produce higher force during dynamic contractions, which is beneficial for movements requiring large power outputs.
AB - Sprinters have been found to possess longer muscle fascicles than non-sprinters, which is thought to be beneficial for high-acceleration movements based on muscle force-length-velocity properties. However, it is unknown if their morphology is a result of genetics or training during growth. To explore the influence of training during growth, thirty guinea fowl (Numida meleagris) were split into exercise and sedentary groups. Exercise birds were housed in a large pen and underwent high-acceleration training during their growth period (age 4–14 weeks), while sedentary birds were housed in small pens to restrict movement. Morphological analyses (muscle mass, PCSA, optimal fascicle length, pennation angle) of a hip extensor muscle (ILPO) and plantarflexor muscle (LG), which differ in architecture and function during running, were performed post-mortem. Muscle mass for both ILPO and LG was not different between the two groups. Exercise birds were found to have ∼12% and ∼14% longer optimal fascicle lengths in ILPO and LG, respectively, than the sedentary group despite having ∼3% shorter limbs. From this study we can conclude that optimal fascicle lengths can increase as a result of high-acceleration training during growth. This increase in optimal fascicle length appears to occur irrespective of muscle architecture and in the absence of a change in muscle mass. Our findings suggest high-acceleration training during growth results in muscles that prioritize adaptations for lower strain and shortening velocity over isometric strength. Thus, the adaptations observed suggest these muscles produce higher force during dynamic contractions, which is beneficial for movements requiring large power outputs.
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U2 - 10.1016/j.jbiomech.2018.09.001
DO - 10.1016/j.jbiomech.2018.09.001
M3 - Article
C2 - 30266195
AN - SCOPUS:85053760825
SN - 0021-9290
VL - 80
SP - 1
EP - 7
JO - Journal of Biomechanics
JF - Journal of Biomechanics
ER -