Exercise-Induced Neuroplasticity in Parkinson’s Disease: A Metasynthesis of the Literature

Table 1

Characteristics of included studies, participants, and assessments.

Study characteristics		Participant characteristics						Assessment details
Author, year	(1) Design, (2) setting, (3) recruitment, (4) inclusion critera age/Hoehn & Yahr	included		Age, mean (SD)		Hoehn & Yahr, mean (SD)		Neuroplasticity evaluation method	Behavioral evaluation
		Exp	Con	Exp	Con	Exp	Con
Angelucci et al., [31]	(1) Single-arm clinical trial, (2) inpatient, (3) not reported, (4) no/2-3	9	_	62.8 (6.7)	_	2.1 (0.6)	_	Blood sampling: levels of BDNF in serum.	UPDRS II-III, PDQ-39, and 6MWT.
Fontanesi et al., [27]	(1) Single-arm clinical trial, (2) inpatient, (3) not reported, (4) no/no	16	_	71.6 (6.8)	_	2.7 (0.4)	_	Blood sampling: evaluation of BDNF-TrkB signaling in lymphocytes.	UPDRS, 6MWT, BBS, TUG, PDDS, FOG-Q.
Frazzitta et al., [28]	(1) Randomized controlled trial, (2) inpatient, (3) recruited from patients admitted to a rehabilitation institute, inclusion, (4) no/1–1.5	15	10	67 (5)	65 (4)	NR	NR	Blood sampling: levels of BDNF in serum.	UPDRS III (training group was also tested on UPDRS total, BBS, and 6MWT)
Zoladz et al., [33]	(1) Single-arm clinical trial, (2) outpatient, (3) not reported, (4) no/no	12	_	70 (10.4)	_	2.3(0.7)	_	Blood sampling: levels of BDNF in serum.	UPDRS total
Batson et al., [35]	(1) Case study, (2) outpatient, (3) recruited from previous intervention group, (4) no/no	1	_	60	_	3	_	Imaging: BOLD fMRI signal during rest and with a reaction time task.	None
Duchesne et al., [32]	(1) Single-arm clinical trial, (2) outpatient (3) not reported, (4) no/1–2	19	_	59 (7.11)	_	2 (0)	_	Imaging: BOLD fMRI signal during a serial reaction time task.	Cardiovascular fitness evaluated through either a submax- or max-test (bike). Reaction times and accuracy on the serial reaction time task.
Maidan et al., [19]	(1) Randomized controlled trial, (2) outpatient, (3) convenience sample from another project, (4) 60–90/2–3	17	17	71.2 (1.7)	71.5 (1.5)	NR	NR	Imaging: BOLD fMRI signal during motor imagery/imagined walking.	Gait speed and stride length during usual walking and obstacle negotiation. Global cognitive function, attention and executive function was assessed using a computerized test battery.
Shah et al., [30]	(1) Randomized controlled trial, (2) outpatient, (3) not reported, (4) 30–65/2–3	13	14	56.5(9.5)	57.2 (7.1)	NR	NR	Imaging: BOLD fMRI-signal during a complex bilateral finger tapping task, during a continuous fingertip force tracking task and during rest.	None
Carvalho et al., 2016	(1) Randomized controlled trial, (2) outpatient, (3) recruited from an outpatient rehabilitation department (4) 45–80/1–3	5 (AT) and 8 (ST)	9	64.8 (11.9) (AT); 64.1 (9.9) (ST)	62.1 (11.7)	2.6 (0.5) (AT); 2.1 (0.6) (ST)	2.3 (0.5)	EEG mean frequency, electrodes divided into six areas: frontal pole, frontal, central, temporal, parietal and occipital.	UPDRS I-IV. Chair-stand test, arm curl test, 2-minute step test, chair sit and reach test, back scratch test, 8-foot up and go test, 10 m walk test, and BBS.
Fisher et al., [25]	(1) Nonrandomized controlled trial, (2) outpatient, (3) recruited from a movement disorder clinic, (4) no/no	5	7 (LI) and 4 (ZI)	NR	NR	NR	NR	Evaluation of corticomotor excitability using single-pulse TMS over the primary motor cortex while monitoring MEPs from the FDI muscle.	UPDRS, 10-meter walk test (both self-selected and as fast as possible) and sit to stand test.
Fisher et al., 2013	(1) Randomized controlled trial, (2) outpatient, (3) subset from ongoing study, (4) no/no	2	2	53.5 (2.1)	56.5 (9.2)	NR	NR	Evaluation of DA-D2R binding potential using PET imaging with [18F]fallypride.	Turning, UPDRS III and total.
del Olmo et al., [36]	(1) Single-arm clinical trial, (2) outpatient, (3) not reported, (4) no/no	9	_	61.2(5.2)	_	1.9 (0.5)	_	Evaluation of metabolic brain activity with PET using 2-deoxy-2[18F]fluoro-D-glucose	Spatiotemporal gait parameters at preferred speed 30 m. Finger tapping for 30 s.
Sehm et al., 2013	(1) Single-arm clinical trial^a, (2) outpatient, (3) recruited from an outpatient clinic, (4) no/no	20	_	62.9 (7.1)	_	2.1 (0.4)	_	Evaluation of grey matter volume using structural MRI.	BBS; behavioral measure: “Time in target,” i.e, the number of seconds participants were able to keep the platform in a horizontal position.

SD calculated from SEM. Abbreviations: BDNF: brain-derived neutrophic factor; UPDRS: Unified Parkinson’s Disease Rating Scale; PDQ-39: Parkinson’s Disease Questionnaire-39; 6MWT: 6-minute walk test; BBS: Berg Balance Scale; TUG: Timed Up and Go; NA: not applicable; NR: not reported; EEG: electroencephalogram; CSP: cortical silent period; 8-FT: 8 Foot Up and Go test; BST: Back Scratch Test; CSRT: Chair Sit and Reach Test; ACT: Arm Curl Test; CST: Chair Stand Test; 2-MST: 2-minute step test; 10mWT: 10-meter walk test; TMS: transcranial magnetic stimulation; PET: positron emission tomography.