Author(s): NERI, M., GATTI, M., DE ICCO, R., BIGHIANI, F., MARTINIS, L., PISANI, A., CALCULLI, A., COMOLLI, D., FAZIO, C., BOTTINELLI, R., PORCELLI, S., Institution: UNIVERSITY OF PAVIA, Country: ITALY, Abstract-ID: 2194

INTRODUCTION:
Parkinson’s disease (PD), the second most common neurodegenerative disease, is characterized by an irreversible loss of dopaminergic neurons in the substantia nigra pars compacta of the basal ganglia, which affects the nervous system, causing motor disturbances (bradykinesia, resting tremor, rigidity, postural instability and gait impairment) [1,2].
Despite it is not clear how alterations in central or peripheral nervous systems controlling skeletal muscle can influence muscle function, PD patients show mitochondrial impairments at skeletal muscle level which can be counteracted by exercise, reducing symptoms and improving patients’ quality of life [1,3,4].
The aim of the study was to highlight the beneficial effects of physical activity training on exercise tolerance and skeletal muscle oxidative capacity in PD patients.

METHODS:
Eleven trained (PD-TR, age: 58±6 years, disease duration: 8.3±6.4 years) and six sedentary (PD-SED, age: 65±10 years, disease duration: 3.7±2.0 years) PD patients were recruited. The level of physical activity was rated by means of IPAQ-Short. Each subject performed an incremental exercise test on a cycle ergometer up to exhaustion to determine Wpeak and V’O2peak. Vastus lateralis (VL) fractional O2 extraction (DHHbMb), non-invasively evaluated by near-infrared spectroscopy (NIRS), was recorded and expressed as % of a reference value obtained during a transient ischaemia of lower limb [5]. Muscle oxidative capacity (mVO2) of VL was estimated by NIRS from recovery rate constant (k) of TSI changes during brief intermittent arterial occlusions [6].
RESULTS:
Wpeak and V’O2peak were higher in PD-TR (232±52 W and 40.1±4.8 ml*kg-1*min-1, respectively) compared to PD-SED (146±36 W and 21.0±1.7 ml*kg-1*min-1, respectively; p<0.01). DHHbMb was higher in PD-TR (68.2±17.1 %) compared to PD-SED (32.4±13.5 %; p<0.01). k was higher in PD-TR (2.52±0.82 min-1) compared to PD-SED (1.39±0.51 min-1, p<0.01). A correlation was found between DHHbMb and k (r=0.77; p<0.001).
CONCLUSION:
The present findings confirm regular physical activity training improves exercise tolerance in PD patients, mainly through an improved muscle oxidative metabolism.

AKNOWLEDGEMENT:
This work was supported by the Italian Ministry of Health "Ricerca Corrente 2022-2024" granted to IRCCS Mondino Foundation.

REFERENCES
[1] Harris et al, J Physiol, 2022
[2] Saiki et al, Sci Rep, 2017
[3] Cardellach et al, Neurology, 1993
[4] Burtscher et al, Int J Mol Sci, 2021
[5] Grassi et al, Med Sci Sports Exerc, 2019
[6] Adami et al, J Appl Physiol, 2018