Figure 1
Flow diagram for different phases of the performed systematic review.
Table 1
Summary of studies.
| Author, Year, Ref | Design | Sample Size (gender, m/f) | Age | Type of exercise | Intervention duration | Types of tremor | Quality | Measure | Main outcomes |
|---|---|---|---|---|---|---|---|---|---|
| Palmer, 1986, [28] | CC | 7 (6, 1) | 63.9 ± 4.4, 65.9 ± 7.2 | slow stretching or upper body karate training in a seated situation | 15-min warm-up, 35-min of karate training and 10-min of cool-down stretching exercise | Resting tremor | High | Rectified envelope of alternating torque while the patient is evaluated by a mental activation task. | Both types of exercises were effective for tremor reduction. |
| King, 2009, [29] | CC | 20 (14, 6) | 64.65 ± 8.56 | Vibration by sound waves | 5 one-minute | Resting, action, and posture tremor | High | UPDRS tremor score | Improvements were seen in motor control symptoms at the time of assessment. |
| Duncan, 2012, [30] | RCT | 26(15,11) | 69.3 ± 1.9 | Tango exercise | 1-hour, twice weekly for 12 months | Resting, action, and posture tremors | High | MDS-UPDRS-3 items 3.15-3.18 | Tremor scores decreased slightly following performing Tango. |
| Ridgel, 2012, [15] | CC | 10(4, 6) | 64 ± 2.1 | Cycling exercise | 30-min pedaling exercise followed by 5-min warm up/cool down session | Resting tremor | Low | Accelerometer and gyroscope sensors | Immediate improvement in tremor and bradykinesia was reported after a single bout of cycling. |
| Stuckenschneider, 2015, [20] | CC | 10(4, 6) | 71.3 ± 4.93 | movements similar to cycling | 12-week active or passive forced exercise, 40-min, three times per week | Resting and postural tremors | High | Frequency of tremor using electronic instrument | Only kinetic tremor was reduced significantly after exercise while rest and postural tremors were not changed significantly. |
| Cikajlo, 2019, [31] | RCT | 10(5, 5) | 69.3 ± 1.9 | Hand movements using a virtual cube pick and place task | 10-section, 3 weeks training strategy using 3D Oculus Rift glass (group1) or 2D laptop screen (group2) | Resting tremor | Low | UPDRS motor section and motion trajectory analysis | 2D environment reduced average tremor better than the 3D environment. |
| Kadkhodaie, 2020, [32] | RCT | 11 (4, 7) | 67.82 ± 9.64 | limb pure eccentric training | 33-45 minutes sessions for a 6-week period, 3 days per week | Resting and postural tremors | High | Amplitude obtained by accelerometer | After the exercise, a significant reduction in resting tremor amplitude was obtained in the intervention group. |
[i] Abbreviations: Randomized control trial (RCT), Case-control (CC), Unified Parkinson’s disease rating scale (UPDRS), Movement Disorder Society-Unified Parkinson’s Disease Rating Scale Item 3(MDS-UPDRS-3), 3 dimensional (3D), two dimensional (2D), male/female (m/f).
Figure 2
Forest plot for the effect of exercise on tremor. The horizontal axis is the crude odds ratio.
Figure 3
Forest plot for the effect of hand movement-based exercise on tremor. The horizontal axis is the adjusted odds ratio.
Figure 4
Funnel plot for the effect of exercise on tremor for PD patients. The line inside the funnel plot shows the regression line.