Table 3 Spatiotemporal parameters of gait analysis and functional motor assessment of participants with PD (Sham vs. Gondola®) at second intervention (6 sessions of stimulation) (T4-T5)

Primary outcome

 Velocity [m/s]

0.73 ± 0.25

0.61 ± 0.20

0.76 ± 0.24

0.76 ± 0.22

0.02 ± 0.10

0.14 ± 0.17

 < 0.001

Secondary outcome

Spatiotemporal parameters of gait analysis

Cadence [stride/min]

105.57 ± 18.85

103.55 ± 14.81

105.67 ± 16.49

103.40 ± 12.70

0.11 ± 9.04

− 0.15 ± 9.74

0.906

Stride length [m]

Stride length

0.85 ± 0.25

0.74 ± 0.23

0.88 ± 0.23

0.88 ± 0.21

0.03 ± 0.11

0.15 ± 0.18

 < 0.001

% Stride length

51.69 ± 14.32

45.54 ± 14.27

53.32 ± 12.94

55.97 ± 14.66

1.63 ± 6.54

10.42 ± 12.28

 < 0.001

Stride duration [s]

1.20 ± 0.28

1.21 ± 0.18

1.20 ± 0.28

1.20 ± 0.16

− 0.001 ± 0.09

-0.006 ± 0.12

0.843

Stance phase [%]

61.22 ± 1.98

61.68 ± 2.14

61.11 ± 2.18

60.87 ± 1.91

− 0.12 ± 2.06

-0.81 ± 2.37

0.182

Swing phase [%]

38.77 ± 1.98

38.31 ± 2.14

38.89 ± 2.18

39.13 ± 1.91

0.12 ± 2.06

0.82 ± 2.38

0.182

Initial phase of double support [%]

11.25 ± 1.96

11.62 ± 2.15

11.04 ± 2.13

10.79 ± 1.89

− 0.20 ± 2.03

-0.82 ± 2.38

0.233

Single support phase [%]

38.62 ± 1.93

38.32 ± 2.11

38.95 ± 2.15

39.20 ± 1.91

0.32 ± 2.07

0.87 ± 2.43

0.303

Propulsion [m/s²]

3.99 ± 1.25

3.42 ± 1.27

4.10 ± 1.40

4.03 ± 1.30

0.11 ± 0.67

0.61 ± 1.04

0.018

Functional motor assessments

FOG-Q (0–24)

10.85 ± 4.46

10.96 ± 5.15

10.71 ± 4.26

9.87 ± 4.59

− 0.14 ± 0.75

− 1.09 ± 1.80

0.012

TUG [s]

22.96 ± 9.84

27.21 ± 23.53

21.32 ± 9.02

20.25 ± 9.07

− 1.64 ± 4.79

− 6.98 ± 16.70

0.109

TUG Dual-task [s]

27.39 ± 13.92

37.15 ± 36.39

29.64 ± 18.76

31.34 ± 29.57

2.25 ± 16.89

− 5.81 ± 16.40

0.066

Mini-BESTest (0–28)

15.42 ± 4.38

14.71 ± 5.79

15.92 ± 4.52

15.93 ± 5.45

0.50 ± 2.06

1.21 ± 1.98

0.174

MDS-UPDRS

 − 2.12

1.71 ± 0.81

1.72 ± 0.89

1.67 ± 0.81

1.69 ± 0.93

− 0.03 ± 0.19

− 0.03 ± 0.47

0.963

 − 2.13

1.64 ± 1.06

1.47 ± 1.13

1.57 ± 1.03

1.28 ± 0.99

− 0.07 ± 0.26

− 0.18 ± 0.39

0.193

 − 3.10

1.82 ± 0.72

2.15 ± 0.92

1.75 ± 0.70

1.87 ± 0.79

− 0.07 ± 0.26

− 0.28 ± 0.52

0.060

 − 3.11

1.39 ± 1.10

1.62 ± 1.23

1.35 ± 1.06

1.22 ± 1.12

− 0.03 ± 0.57

− 0.40 ± 0.50

0.010

 − 3.12

1.96 ± 1.10

2.09 ± 1.09

1.89 ± 0.99

1.90 ± 0.99

− 0.07 ± 0.71

− 0.18 ± 0.53

0.477