Effects of High-Intensity Interval Training and Isoinertial Training on Leg Extensors Muscle Function, Structure, and Intermuscular Adipose Tissue in Older Adults

Frontiers in Physiology

Paolo Bruseghini¹  Enrico Tam²  Carlo Capelli²  Elisa Calabria²  Andrea P. Rossi⁴ 

[1] Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy;Department of Neurological and Movement Sciences, School of Sport and Exercise Sciences, University of Verona, Verona, Italy;Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway;Section of Geriatrics, Department of Medicine, University of Verona, Verona, Italy;

关键词: aging;    high-intensity interval training;    isoinertial resistance training;    muscle volume;    muscle architecture;    muscle activation;   

DOI  :  10.3389/fphys.2019.01260

来源: DOAJ

【 摘 要 】

We compared the effects of aerobic high-intensity training (HIT) and isoinertial resistance training (IRT) on the strength, mass, architecture, intermuscular adipose tissue (IMAT) quality, and neuromuscular activation of the quadriceps in elderly subjects. Twelve healthy men (69.3 ± 4.2 years; 77.8 ± 10.4 kg; 1.72 ± 0.05 m) were exposed to 8 weeks of HIT (7 × 2-min cycling repetitions at 90% of V.O2peak, 3 times/week) and, after 4 months (detraining), to IRT (4 × 7 maximal concentric–eccentric knee extensions, 3 times/week). Before and after trainings, we measured knee extension isometric (TMVC) and dynamic (TC) maximal concentric torque, anatomical cross-sectional area (ACSA) at 25, 50, and 75% of femur length, quadriceps volume (Vol), IMAT, pennation angle (θp) of the fibers from the vastus lateralis, and voluntary activation (%Act). TMVC and TC were significantly larger only after IRT (P = 0.008); IRT was able to elicit a greater increase of ACSA than HIT; Vol increases similarly and significantly after HIT and IRT (P = 0.003–0.001); IMAT at 50% of femur length decreased after both HIT and IRT (P = 0.001–0.003); physiological cross-sectional area (PCSA) was larger after IRT than before (P = 0.025); specific torque did not change throughout the study (45.5 N cm–2 ± 12.0); %Act of the quadriceps was significantly affected only by IRT (P = 0.011). Both HIT and IRT are able to elicit beneficial modifications of muscular mass, architecture, and quality (reducing IMAT) in elderly subjects in connection with an amelioration of strength. HIT and IRT caused a homogeneous increase of ACSA and of Vol of the quadriceps. PCSA increases, but specific strength per unit of PCSA did not change. The increases of functional torque seemed to be attributed to a parallel increase of %Act and muscle hypertrophy only after IRT. Data suggest that IMAT may be a prominent indicator to track metabolic-dependent activity and skeletal muscle quality.

【 授权许可】

Unknown