Home-based aerobic exercise training improves skeletal muscle oxidative metabolism in patients with metabolic myopathies

Abstract

Aerobic training can be effective in patients with mitochondrial myopathies (MM) and McArdle's disease (McA). The aim of the study was to use noninvasive functional evaluation methods, specifically aimed at skeletal muscle oxidative metabolism, to evaluate the effects of an aerobic exercise training (cycle ergometer, 12 wk, 4 days/wk, ∼65-70% of maximal heart rate) in 6 MM and 7 McA. Oxygen uptake and skeletal muscle vastus lateralis fractional O2 extraction by near-infrared spectroscopy were assessed during incremental and low-intensity constant work rate (CWR) exercises before (BEFORE) and at the end (AFTER) of training. Peak O2 uptake increased significantly with training both in MM [14.7 ± 1.2 vs. 17.6 ± 1.4 ml·kg(-1)·min(-1) (mean ± SD)] and in McA (18.5 ± 1.8 ml·kg(-1)·min(-1) vs. 21.6 ± 1.9). Peak skeletal muscle fractional O2 extraction increased with training both in MM (22.0 ± 6.7 vs. 32.6 ± 5.9%) and in McA (18.5 ± 6.2 vs. 37.2 ± 7.2%). During low-intensity CWR in both MM and McA: V̇o2 kinetics became faster in AFTER, but only in the patients with slow V̇o2 kinetics in BEFORE; the transient overshoot in fractional O2 extraction kinetics disappeared. The level of habitual physical activity was not higher 3 mo after training (FOLLOW-UP vs. PRE). In MM and McA patients a home-based aerobic training program significantly attenuated the impairment of skeletal muscle oxidative metabolism and improved variables associated with exercise tolerance. Our findings indicate that in MM and McA patients near-infrared spectroscopy and V̇o2 kinetics can effectively detect the functional improvements obtained by training.

PlanHab*: hypoxia does not worsen the impairment of skeletal muscle oxidative function induced by bed rest alone

“…The dynamic profiles of ∆[deoxy(Hb + Mb)] during the first 2 min of unloaded knee extension were analysed to evaluate parameters related to the intramuscular matching between O 2 delivery and O 2 consumption in the vastus lateralis muscle (Porcelli et al . , , ; Grassi & Quaresima, ; Salvadego et al . ).…”

“…), as well as in patients with metabolic myopathies (Porcelli et al . , ). According to another possibility, the transient overshoot in O 2 extraction may be the consequence of an accumulation of blood in skeletal muscle at rest, which has been hypothesized to occur during bed rest (Rittweger et al .…”

Higher oxidative stress in skeletal muscle of McArdle disease patients

“…It has been reported that aerobic training decreases serum CK activity in MCD patients [7]. In addition, it has been reported that aerobic training program significantly attenuated the impairment of skeletal muscle oxidative metabolism and improved variables associated with exercise tolerance [11], [59]. In contrast, deconditioning [60], immobilization [61] or age-related changes (decline of physical activity) [19], [62], lead to higher oxidative stress which may be very similar to MCD patients where the level of physical activity is low.…”

Side alternating vibration training in patients with mitochondrial disease: a pilot study

“…Furthermore, we have recently established PJP as a novel quantitative measurement shown to classify levels of ambulatory ability for patients with rare neuromuscular disorders, including mitochondrial disease [ 19 ]. The benefits of exercise in patients with mitochondrial disease has also been well established [ 21 ], with evidence for improved oxidative metabolism [ 22 ], mitochondrial proliferation [ 23 ], and gene-shifting from the recruitment of satellite cells [ 24 ] to name just a few mechanisms. SAVT can improve truncal strength [ 25 ], improve muscle function from exercise induced muscle damage [ 26 ], and attenuate the effects of aging on skeletal muscle [ 26 ].…”