Comparison of Mitochondrial Respiration in M. triceps brachii and M. vastus lateralis Between Elite Cross-Country Skiers and Physically Active Controls.

Berg, Jonathan; Undebakke, Vidar; Rasch-Halvorsen, Øystein; Aakerøy, Lars; Sandbakk, Øyvind; Tjønna, Arnt Erik

Rationale: The main purposes of this study were to compare mitochondrial respiration in M. triceps brachii and M. vastus lateralis between elite cross-country (XC) skiers and physically active controls (CON), and to explore the associations between mitochondrial respiration in these muscles and peak oxygen uptake (V ˙ O2peak) in arm- and leg-dominant exercise modes. Methods: Thirteen male elite XC skiers (age: 25 ± 4; peak oxygen uptake (V ˙ O2peak): 75.5 ± 4.2 mL⋅kg-1⋅min-1) and twelve CON (age: 26 ± 3; V ˙ O2peak: 57.2 ± 6.4 mL⋅kg-1⋅min-1) had microbiopsies taken from M. vastus lateralis and M. triceps brachii, which were analyzed for various measures of mitochondrial respiration using high-resolution respirometry. Thereafter, all participants tested V ˙ O2peak in both running (RUN) and upper body poling (UBP). Results: XC skiers had generally higher mitochondrial respiration in M. triceps brachii compared to CON (P 2peak in UBP and mitochondrial respiration in M. triceps brachii on several measures (P 2peak in UBP indicate that arm muscles' respiratory function may be a limiting factor for V ˙ O2peak in arm-dominant exercise modes.

TRICEPS; SKIERS; VASTUS medialis; MUSCLE mitochondria; PHYSICAL activity

Frontiers in Physiology, 2019, pN.PAG

1664-042X

Academic Journal

10.3389/fphys.2019.00365