, new research suggests.
A meta-analysis, which included 18 randomized controlled trials and more than 1,000 patients with Parkinson’s disease, showed that those who underwent resistance training had significantly greater improvement in motor impairment, muscle strength, and mobility/balance than their peers who underwent passive or placebo interventions.
However, there was no significant difference between patients who participated in resistance training and those who participated in other active physical interventions, including yoga.
Overall, the results highlight the importance that these patients should participate in some type of physical exercise, said the study’s lead author, Romina Gollan, MSc, an assistant researcher in the division of medical psychology, University of Cologne, Germany. “Patients should definitely be doing exercises, including resistance training, if they want to. But the type of exercise is of secondary interest,” she said.
The findings were presented at the International Congress of Parkinson’s Disease and Movement Disorders.
Positive but inconsistent
Previous reviews have suggested resistance training has positive effects on motor function in Parkinson’s disease. However, results from the included studies were inconsistent; and few reviews have examined nonmotor outcomes of resistance training in this population, the investigators noted.
After carrying out a literature search of studies that examined the effects of resistance training in Parkinson’s disease, the researchers included 18 randomized controlled trials in their current review. Among the 1,134 total participants, the mean age was 66 years, the mean Hoehn & Yahr stage was 2.3 (range 0-4), and the mean duration of Parkinson’s disease was 7.5 years.
The investigation was grouped into two meta-analysis groups: one examining resistance training versus a passive or placebo intervention and the other assessing resistance training versus active physical interventions, such as yoga.
During resistance training, participants use their full strength to do a repetition, working muscles to overcome a certain threshold, said Ms. Gollan. In contrast, a placebo intervention is “very low intensity” and involves a much lower threshold, she added.
Passive interventions include such things as stretching where the stimulus “is not high enough for muscles to adapt” and build strength, Ms. Gollan noted.
A passive intervention might also include “treatment as usual” or normal daily routines.
Patient preference important
The meta-analysis comparing resistance training groups with passive control groups showed significant large effects on muscle strength (standard mean difference, –0.84; 95% confidence interval, –1.29 to –0.39; P = .0003), motor impairment (SMD, –0.81; 95% CI, –1.34 to –0.27; P = .003), and mobility and balance (SMD, –1.80; 95% CI, –3.13 to –0.49; P = .007).
The review also showed significant but small effects on quality of life.
However, the meta-analysis that assessed resistance training versus other physical interventions showed no significant between-group differences.
Ms. Gollan noted that although there were some assessments of cognition and depression, the data were too limited to determine the impact of resistance training on these outcomes.
“We need more studies, especially randomized controlled trials, to investigate the effects of resistance training on nonmotor outcomes like depression and cognition,” she said.
Co-investigator Ann-Kristin Folkerts, PhD, who heads the University of Cologne medical psychology working group, noted that although exercise in general is beneficial for patients with Parkinson’s disease, the choice of activity should take patient preferences into consideration.
It is important that patients choose an exercise they enjoy “because otherwise they probably wouldn’t adhere to the treatment,” Dr. Folkerts said. “It’s important to have fun.”
Specific goals or objectives, such as improving quality of life or balance, should also be considered, she added.