Single muscle fibre contractile characteristics with lifelong endurance exercise
Key points A hallmark trait of ageing skeletal muscle health is a reduction in size and function, which is most pronounced in the fast muscle fibres. We studied older men (74 ± 4 years) with a history of lifelong (>50 years) endurance exercise to examine potential benefits for slow and fast muscl...
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| Veröffentlicht in: | The Journal of physiology 2021-07, Vol.599 (14), p.3549-3565 |
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| creator | Grosicki, Gregory J. Gries, Kevin J. Minchev, Kiril Raue, Ulrika Chambers, Toby L. Begue, Gwénaëlle Finch, Holmes Graham, Bruce Trappe, Todd A. Trappe, Scott |
| description | Key points
A hallmark trait of ageing skeletal muscle health is a reduction in size and function, which is most pronounced in the fast muscle fibres.
We studied older men (74 ± 4 years) with a history of lifelong (>50 years) endurance exercise to examine potential benefits for slow and fast muscle fibre size and contractile function.
Lifelong endurance exercisers had slow muscle fibres that were larger, stronger, faster and more powerful than young exercisers (25 ± 1 years) and age‐matched non‐exercisers (75 ± 2 years).
Limited benefits with lifelong endurance exercise were noted in the fast muscle fibres.
These findings suggest that additional exercise modalities (e.g. resistance exercise) or other therapeutic interventions are needed to target fast muscle fibres with age.
We investigated single muscle fibre size and contractile function among three groups of men: lifelong exercisers (LLE) (n = 21, 74 ± 4 years), old healthy non‐exercisers (OH) (n = 10, 75 ± 2 years) and young exercisers (YE) (n = 10, 25 ± 1 years). On average, LLE had exercised ∼5 days week–1 for ∼7 h week–1 over the past 53 ± 6 years. LLE were subdivided based on lifelong exercise intensity into performance (LLE‐P) (n = 14) and fitness (LLE‐F) (n = 7). Muscle biopsies (vastus lateralis) were examined for myosin heavy chain (MHC) slow (MHC I) and fast (MHC IIa) fibre size and function (strength, speed, power). LLE MHC I size (7624 ± 2765 μm2) was 25–40% larger (P |
| doi_str_mv | 10.1113/JP281666 |
| format | Article |
| fullrecord | <record><control><sourceid>proquest_cross</sourceid><recordid>TN_cdi_proquest_miscellaneous_2532258520</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>2532258520</sourcerecordid><originalsourceid>FETCH-LOGICAL-c3612-19d269853fed10d899a89c43985b8fa4e435fadb6ea53967098e447272f470ce3</originalsourceid><addsrcrecordid>eNp1kUtLAzEUhYMoWKvgTxhw42Zq3pMspfgqBQvW9ZBmbtqU6UxNZqj996ZUEQRX53L4OFzOQeia4BEhhN1NZlQRKeUJGhAudV4Ump2iAcaU5qwQ5BxdxLjGmDCs9QDN3nyzrCHb9NEmcX4RILNt0wVjO58cuzKHE4KPnbcx2_luldXeQd02ywyaqg-msZDBJwTrI1yiM2fqCFffOkTvjw_z8XM-fX16Gd9Pc8skoTnRFZVaCeagIrhSWhulLWfJWihnOHAmnKkWEoxgWhZYK-C8oAV1vMAW2BDdHnO3of3oIXblxkcLdW0aaPtYUsEoFUpQnNCbP-i67UOTvkuUIBxjhfFvoA1tjAFcuQ1-Y8K-JLg8VFv-VJvQ0RHdpYb2_3LlfDI7bEDZF7TveGE</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>2551400800</pqid></control><display><type>article</type><title>Single muscle fibre contractile characteristics with lifelong endurance exercise</title><source>Wiley Journals</source><source>Wiley Free Content</source><source>EZB-FREE-00999 freely available EZB journals</source><source>PubMed Central</source><creator>Grosicki, Gregory J. ; Gries, Kevin J. ; Minchev, Kiril ; Raue, Ulrika ; Chambers, Toby L. ; Begue, Gwénaëlle ; Finch, Holmes ; Graham, Bruce ; Trappe, Todd A. ; Trappe, Scott</creator><creatorcontrib>Grosicki, Gregory J. ; Gries, Kevin J. ; Minchev, Kiril ; Raue, Ulrika ; Chambers, Toby L. ; Begue, Gwénaëlle ; Finch, Holmes ; Graham, Bruce ; Trappe, Todd A. ; Trappe, Scott</creatorcontrib><description>Key points
A hallmark trait of ageing skeletal muscle health is a reduction in size and function, which is most pronounced in the fast muscle fibres.
We studied older men (74 ± 4 years) with a history of lifelong (>50 years) endurance exercise to examine potential benefits for slow and fast muscle fibre size and contractile function.
Lifelong endurance exercisers had slow muscle fibres that were larger, stronger, faster and more powerful than young exercisers (25 ± 1 years) and age‐matched non‐exercisers (75 ± 2 years).
Limited benefits with lifelong endurance exercise were noted in the fast muscle fibres.
These findings suggest that additional exercise modalities (e.g. resistance exercise) or other therapeutic interventions are needed to target fast muscle fibres with age.
We investigated single muscle fibre size and contractile function among three groups of men: lifelong exercisers (LLE) (n = 21, 74 ± 4 years), old healthy non‐exercisers (OH) (n = 10, 75 ± 2 years) and young exercisers (YE) (n = 10, 25 ± 1 years). On average, LLE had exercised ∼5 days week–1 for ∼7 h week–1 over the past 53 ± 6 years. LLE were subdivided based on lifelong exercise intensity into performance (LLE‐P) (n = 14) and fitness (LLE‐F) (n = 7). Muscle biopsies (vastus lateralis) were examined for myosin heavy chain (MHC) slow (MHC I) and fast (MHC IIa) fibre size and function (strength, speed, power). LLE MHC I size (7624 ± 2765 μm2) was 25–40% larger (P < 0.001) than YE (6106 ± 1710 μm2) and OH (5476 ± 2467 μm2). LLE MHC I fibres were ∼20% stronger, ∼10% faster and ∼30% more powerful than YE and OH (P < 0.05). By contrast, LLE MHC IIa size (6466 ± 2659 μm2) was similar to OH (6237 ± 2525 μm2; P = 0.854), with both groups ∼20% smaller (P < 0.001) than YE (7860 ± 1930 μm2). MHC IIa contractile function was variable across groups, with a hierarchical pattern (OH > LLE > YE; P < 0.05) in normalized power among OH (16.7 ± 6.4 W L–1), LLE (13.9 ± 4.5 W L–1) and YE (12.4 ± 3.5 W L–1). The LLE‐P and LLE‐F had similar single fibre profiles with MHC I power driven by speed (LLE‐P) or force (LLE‐F), suggesting exercise intensity impacted slow muscle fibre mechanics. These data suggest that lifelong endurance exercise benefited slow muscle fibre size and function. Comparable fast fibre characteristics between LLE and OH, regardless of training intensity, suggest other exercise modes (e.g. resistance training) or myotherapeutics may be necessary to preserve fast muscle fibre size and performance with age.
Key points
A hallmark trait of ageing skeletal muscle health is a reduction in size and function, which is most pronounced in the fast muscle fibres.
We studied older men (74 ± 4 years) with a history of lifelong (>50 years) endurance exercise to examine potential benefits for slow and fast muscle fibre size and contractile function.
Lifelong endurance exercisers had slow muscle fibres that were larger, stronger, faster and more powerful than young exercisers (25 ± 1 years) and age‐matched non‐exercisers (75 ± 2 years).
Limited benefits with lifelong endurance exercise were noted in the fast muscle fibres.
These findings suggest that additional exercise modalities (e.g. resistance exercise) or other therapeutic interventions are needed to target fast muscle fibres with age.</description><identifier>ISSN: 0022-3751</identifier><identifier>EISSN: 1469-7793</identifier><identifier>DOI: 10.1113/JP281666</identifier><language>eng</language><publisher>London: Wiley Subscription Services, Inc</publisher><subject>ageing ; contractile function ; Exercise ; Exercise intensity ; masters athletes ; Muscle contraction ; myocellular ; Myosin ; physical activity ; Physical training ; Power</subject><ispartof>The Journal of physiology, 2021-07, Vol.599 (14), p.3549-3565</ispartof><rights>2021 The Authors. The Journal of Physiology © 2021 The Physiological Society</rights><rights>Journal compilation © 2021 The Physiological Society</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c3612-19d269853fed10d899a89c43985b8fa4e435fadb6ea53967098e447272f470ce3</citedby><cites>FETCH-LOGICAL-c3612-19d269853fed10d899a89c43985b8fa4e435fadb6ea53967098e447272f470ce3</cites><orcidid>0000-0002-6438-431X</orcidid></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://onlinelibrary.wiley.com/doi/pdf/10.1113%2FJP281666$$EPDF$$P50$$Gwiley$$H</linktopdf><linktohtml>$$Uhttps://onlinelibrary.wiley.com/doi/full/10.1113%2FJP281666$$EHTML$$P50$$Gwiley$$H</linktohtml><link.rule.ids>314,780,784,1417,1433,27924,27925,45574,45575,46409,46833</link.rule.ids></links><search><creatorcontrib>Grosicki, Gregory J.</creatorcontrib><creatorcontrib>Gries, Kevin J.</creatorcontrib><creatorcontrib>Minchev, Kiril</creatorcontrib><creatorcontrib>Raue, Ulrika</creatorcontrib><creatorcontrib>Chambers, Toby L.</creatorcontrib><creatorcontrib>Begue, Gwénaëlle</creatorcontrib><creatorcontrib>Finch, Holmes</creatorcontrib><creatorcontrib>Graham, Bruce</creatorcontrib><creatorcontrib>Trappe, Todd A.</creatorcontrib><creatorcontrib>Trappe, Scott</creatorcontrib><title>Single muscle fibre contractile characteristics with lifelong endurance exercise</title><title>The Journal of physiology</title><description>Key points
A hallmark trait of ageing skeletal muscle health is a reduction in size and function, which is most pronounced in the fast muscle fibres.
We studied older men (74 ± 4 years) with a history of lifelong (>50 years) endurance exercise to examine potential benefits for slow and fast muscle fibre size and contractile function.
Lifelong endurance exercisers had slow muscle fibres that were larger, stronger, faster and more powerful than young exercisers (25 ± 1 years) and age‐matched non‐exercisers (75 ± 2 years).
Limited benefits with lifelong endurance exercise were noted in the fast muscle fibres.
These findings suggest that additional exercise modalities (e.g. resistance exercise) or other therapeutic interventions are needed to target fast muscle fibres with age.
We investigated single muscle fibre size and contractile function among three groups of men: lifelong exercisers (LLE) (n = 21, 74 ± 4 years), old healthy non‐exercisers (OH) (n = 10, 75 ± 2 years) and young exercisers (YE) (n = 10, 25 ± 1 years). On average, LLE had exercised ∼5 days week–1 for ∼7 h week–1 over the past 53 ± 6 years. LLE were subdivided based on lifelong exercise intensity into performance (LLE‐P) (n = 14) and fitness (LLE‐F) (n = 7). Muscle biopsies (vastus lateralis) were examined for myosin heavy chain (MHC) slow (MHC I) and fast (MHC IIa) fibre size and function (strength, speed, power). LLE MHC I size (7624 ± 2765 μm2) was 25–40% larger (P < 0.001) than YE (6106 ± 1710 μm2) and OH (5476 ± 2467 μm2). LLE MHC I fibres were ∼20% stronger, ∼10% faster and ∼30% more powerful than YE and OH (P < 0.05). By contrast, LLE MHC IIa size (6466 ± 2659 μm2) was similar to OH (6237 ± 2525 μm2; P = 0.854), with both groups ∼20% smaller (P < 0.001) than YE (7860 ± 1930 μm2). MHC IIa contractile function was variable across groups, with a hierarchical pattern (OH > LLE > YE; P < 0.05) in normalized power among OH (16.7 ± 6.4 W L–1), LLE (13.9 ± 4.5 W L–1) and YE (12.4 ± 3.5 W L–1). The LLE‐P and LLE‐F had similar single fibre profiles with MHC I power driven by speed (LLE‐P) or force (LLE‐F), suggesting exercise intensity impacted slow muscle fibre mechanics. These data suggest that lifelong endurance exercise benefited slow muscle fibre size and function. Comparable fast fibre characteristics between LLE and OH, regardless of training intensity, suggest other exercise modes (e.g. resistance training) or myotherapeutics may be necessary to preserve fast muscle fibre size and performance with age.
Key points
A hallmark trait of ageing skeletal muscle health is a reduction in size and function, which is most pronounced in the fast muscle fibres.
We studied older men (74 ± 4 years) with a history of lifelong (>50 years) endurance exercise to examine potential benefits for slow and fast muscle fibre size and contractile function.
Lifelong endurance exercisers had slow muscle fibres that were larger, stronger, faster and more powerful than young exercisers (25 ± 1 years) and age‐matched non‐exercisers (75 ± 2 years).
Limited benefits with lifelong endurance exercise were noted in the fast muscle fibres.
These findings suggest that additional exercise modalities (e.g. resistance exercise) or other therapeutic interventions are needed to target fast muscle fibres with age.</description><subject>ageing</subject><subject>contractile function</subject><subject>Exercise</subject><subject>Exercise intensity</subject><subject>masters athletes</subject><subject>Muscle contraction</subject><subject>myocellular</subject><subject>Myosin</subject><subject>physical activity</subject><subject>Physical training</subject><subject>Power</subject><issn>0022-3751</issn><issn>1469-7793</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2021</creationdate><recordtype>article</recordtype><recordid>eNp1kUtLAzEUhYMoWKvgTxhw42Zq3pMspfgqBQvW9ZBmbtqU6UxNZqj996ZUEQRX53L4OFzOQeia4BEhhN1NZlQRKeUJGhAudV4Ump2iAcaU5qwQ5BxdxLjGmDCs9QDN3nyzrCHb9NEmcX4RILNt0wVjO58cuzKHE4KPnbcx2_luldXeQd02ywyaqg-msZDBJwTrI1yiM2fqCFffOkTvjw_z8XM-fX16Gd9Pc8skoTnRFZVaCeagIrhSWhulLWfJWihnOHAmnKkWEoxgWhZYK-C8oAV1vMAW2BDdHnO3of3oIXblxkcLdW0aaPtYUsEoFUpQnNCbP-i67UOTvkuUIBxjhfFvoA1tjAFcuQ1-Y8K-JLg8VFv-VJvQ0RHdpYb2_3LlfDI7bEDZF7TveGE</recordid><startdate>20210701</startdate><enddate>20210701</enddate><creator>Grosicki, Gregory J.</creator><creator>Gries, Kevin J.</creator><creator>Minchev, Kiril</creator><creator>Raue, Ulrika</creator><creator>Chambers, Toby L.</creator><creator>Begue, Gwénaëlle</creator><creator>Finch, Holmes</creator><creator>Graham, Bruce</creator><creator>Trappe, Todd A.</creator><creator>Trappe, Scott</creator><general>Wiley Subscription Services, Inc</general><scope>AAYXX</scope><scope>CITATION</scope><scope>7QP</scope><scope>7QR</scope><scope>7TK</scope><scope>7TS</scope><scope>8FD</scope><scope>FR3</scope><scope>P64</scope><scope>7X8</scope><orcidid>https://orcid.org/0000-0002-6438-431X</orcidid></search><sort><creationdate>20210701</creationdate><title>Single muscle fibre contractile characteristics with lifelong endurance exercise</title><author>Grosicki, Gregory J. ; Gries, Kevin J. ; Minchev, Kiril ; Raue, Ulrika ; Chambers, Toby L. ; Begue, Gwénaëlle ; Finch, Holmes ; Graham, Bruce ; Trappe, Todd A. ; Trappe, Scott</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c3612-19d269853fed10d899a89c43985b8fa4e435fadb6ea53967098e447272f470ce3</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2021</creationdate><topic>ageing</topic><topic>contractile function</topic><topic>Exercise</topic><topic>Exercise intensity</topic><topic>masters athletes</topic><topic>Muscle contraction</topic><topic>myocellular</topic><topic>Myosin</topic><topic>physical activity</topic><topic>Physical training</topic><topic>Power</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Grosicki, Gregory J.</creatorcontrib><creatorcontrib>Gries, Kevin J.</creatorcontrib><creatorcontrib>Minchev, Kiril</creatorcontrib><creatorcontrib>Raue, Ulrika</creatorcontrib><creatorcontrib>Chambers, Toby L.</creatorcontrib><creatorcontrib>Begue, Gwénaëlle</creatorcontrib><creatorcontrib>Finch, Holmes</creatorcontrib><creatorcontrib>Graham, Bruce</creatorcontrib><creatorcontrib>Trappe, Todd A.</creatorcontrib><creatorcontrib>Trappe, Scott</creatorcontrib><collection>CrossRef</collection><collection>Calcium & Calcified Tissue Abstracts</collection><collection>Chemoreception Abstracts</collection><collection>Neurosciences Abstracts</collection><collection>Physical Education Index</collection><collection>Technology Research Database</collection><collection>Engineering Research Database</collection><collection>Biotechnology and BioEngineering Abstracts</collection><collection>MEDLINE - Academic</collection><jtitle>The Journal of physiology</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Grosicki, Gregory J.</au><au>Gries, Kevin J.</au><au>Minchev, Kiril</au><au>Raue, Ulrika</au><au>Chambers, Toby L.</au><au>Begue, Gwénaëlle</au><au>Finch, Holmes</au><au>Graham, Bruce</au><au>Trappe, Todd A.</au><au>Trappe, Scott</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Single muscle fibre contractile characteristics with lifelong endurance exercise</atitle><jtitle>The Journal of physiology</jtitle><date>2021-07-01</date><risdate>2021</risdate><volume>599</volume><issue>14</issue><spage>3549</spage><epage>3565</epage><pages>3549-3565</pages><issn>0022-3751</issn><eissn>1469-7793</eissn><abstract>Key points
A hallmark trait of ageing skeletal muscle health is a reduction in size and function, which is most pronounced in the fast muscle fibres.
We studied older men (74 ± 4 years) with a history of lifelong (>50 years) endurance exercise to examine potential benefits for slow and fast muscle fibre size and contractile function.
Lifelong endurance exercisers had slow muscle fibres that were larger, stronger, faster and more powerful than young exercisers (25 ± 1 years) and age‐matched non‐exercisers (75 ± 2 years).
Limited benefits with lifelong endurance exercise were noted in the fast muscle fibres.
These findings suggest that additional exercise modalities (e.g. resistance exercise) or other therapeutic interventions are needed to target fast muscle fibres with age.
We investigated single muscle fibre size and contractile function among three groups of men: lifelong exercisers (LLE) (n = 21, 74 ± 4 years), old healthy non‐exercisers (OH) (n = 10, 75 ± 2 years) and young exercisers (YE) (n = 10, 25 ± 1 years). On average, LLE had exercised ∼5 days week–1 for ∼7 h week–1 over the past 53 ± 6 years. LLE were subdivided based on lifelong exercise intensity into performance (LLE‐P) (n = 14) and fitness (LLE‐F) (n = 7). Muscle biopsies (vastus lateralis) were examined for myosin heavy chain (MHC) slow (MHC I) and fast (MHC IIa) fibre size and function (strength, speed, power). LLE MHC I size (7624 ± 2765 μm2) was 25–40% larger (P < 0.001) than YE (6106 ± 1710 μm2) and OH (5476 ± 2467 μm2). LLE MHC I fibres were ∼20% stronger, ∼10% faster and ∼30% more powerful than YE and OH (P < 0.05). By contrast, LLE MHC IIa size (6466 ± 2659 μm2) was similar to OH (6237 ± 2525 μm2; P = 0.854), with both groups ∼20% smaller (P < 0.001) than YE (7860 ± 1930 μm2). MHC IIa contractile function was variable across groups, with a hierarchical pattern (OH > LLE > YE; P < 0.05) in normalized power among OH (16.7 ± 6.4 W L–1), LLE (13.9 ± 4.5 W L–1) and YE (12.4 ± 3.5 W L–1). The LLE‐P and LLE‐F had similar single fibre profiles with MHC I power driven by speed (LLE‐P) or force (LLE‐F), suggesting exercise intensity impacted slow muscle fibre mechanics. These data suggest that lifelong endurance exercise benefited slow muscle fibre size and function. Comparable fast fibre characteristics between LLE and OH, regardless of training intensity, suggest other exercise modes (e.g. resistance training) or myotherapeutics may be necessary to preserve fast muscle fibre size and performance with age.
Key points
A hallmark trait of ageing skeletal muscle health is a reduction in size and function, which is most pronounced in the fast muscle fibres.
We studied older men (74 ± 4 years) with a history of lifelong (>50 years) endurance exercise to examine potential benefits for slow and fast muscle fibre size and contractile function.
Lifelong endurance exercisers had slow muscle fibres that were larger, stronger, faster and more powerful than young exercisers (25 ± 1 years) and age‐matched non‐exercisers (75 ± 2 years).
Limited benefits with lifelong endurance exercise were noted in the fast muscle fibres.
These findings suggest that additional exercise modalities (e.g. resistance exercise) or other therapeutic interventions are needed to target fast muscle fibres with age.</abstract><cop>London</cop><pub>Wiley Subscription Services, Inc</pub><doi>10.1113/JP281666</doi><tpages>17</tpages><orcidid>https://orcid.org/0000-0002-6438-431X</orcidid><oa>free_for_read</oa></addata></record> |
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| source | Wiley Journals; Wiley Free Content; EZB-FREE-00999 freely available EZB journals; PubMed Central |
| subjects | ageing contractile function Exercise Exercise intensity masters athletes Muscle contraction myocellular Myosin physical activity Physical training Power |
| title | Single muscle fibre contractile characteristics with lifelong endurance exercise |
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