1. Free essential amino acid feeding improves endurance during resistance training via DRP1‐dependent mitochondrial remodelling
- Author
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Jiwoong Jang, Yeongmin Kim, Taejeong Song, Sanghee Park, Hee‐Joo Kim, Jin‐ho Koh, Yoonil Cho, Shi‐Young Park, Sakthivel Sadayappan, Hyo‐Bum Kwak, Robert R. Wolfe, Il‐Young Kim, and Cheol Soo Choi
- Subjects
Metabolic flux ,Mitochondrial dynamics ,Muscle mass ,Physical performance ,Protein synthesis rate ,Neuromuscular junction stability ,Diseases of the musculoskeletal system ,RC925-935 ,Human anatomy ,QM1-695 - Abstract
Abstract Background Loss of muscle strength and endurance with aging or in various conditions negatively affects quality of life. Resistance exercise training (RET) is the most powerful means to improve muscle mass and strength, but it does not generally lead to improvements in endurance capacity. Free essential amino acids (EAAs) act as precursors and stimuli for synthesis of both mitochondrial and myofibrillar proteins that could potentially confer endurance and strength gains. Thus, we hypothesized that daily consumption of a dietary supplement of nine free EAAs with RET improves endurance in addition to the strength gains by RET. Methods Male C57BL6J mice (9 weeks old) were assigned to control (CON), EAA, RET (ladder climbing, 3 times a week), or combined treatment of EAA and RET (EAA + RET) groups. Physical functions focusing on strength or endurance were assessed before and after the interventions. Several analyses were performed to gain better insight into the mechanisms by which muscle function was improved. We determined cumulative rates of myofibrillar and mitochondrial protein synthesis using 2H2O labelling and mass spectrometry; assessed ex vivo contractile properties and in vitro mitochondrial function, evaluated neuromuscular junction (NMJ) stability, and assessed implicated molecular singling pathways. Furthermore, whole‐body and muscle insulin sensitivity along with glucose metabolism, were evaluated using a hyperinsulinaemic–euglycaemic clamp. Results EAA + RET increased muscle mass (10%, P
- Published
- 2024
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