Parkinson Disease (PD) is a common neurodegenerative disorder. Progressive rigidity, tremor, slowness, and falls, along with myriad non-motor symptoms rob patients of quality of life.1 Pharmacologic therapy can mitigate symptoms but has not been shown to protect the brain from further damage and degeneration.2,3 Non-pharmacologic therapy—in particular exercise—can also improve symptoms. There is speculation that exercise may even slow disease progression and protect neurons.4–6 While many exercises such as dance,7 tai-chi,8,9 running,6 boxing,10–12 Nordic walking,13,14 qigong,15 and aquatic exercise16,17 have demonstrated efficacy in small clinical trials, few studies11 have examined the implementation and effectiveness of these interventions in the real-world setting. Lack of evidence regarding feasibility and effectiveness of exercise may be one barrier to its routine prescription for individuals with PD.
Hybrid trials blending implementation and effectiveness research may shorten the time gap between research discovery and routine uptake. Based on the framework proposed by Curran et al. in their 2012 paper18 detailing methods for blending clinical effectiveness and implementation research, we designed a type 3 hybrid trial to test implementation and observe effectiveness of the Pedaling for Parkinson’s™ (PFP) program19—a community-based high-cadence cycling intervention.
We chose to study the PFP cycling program for two reasons. First, cycling may be especially beneficial because it is often inexplicably but remarkably preserved in individuals with advanced PD who would never be able to run or complete many of the other exercise interventions available.20,21 Second, PFP was designed based on the results of several clinical trials examining forced high cadence cycling (FHCC), which have been found to be effective at improving Parkinson’s symptoms. While PFP does not utilize FHCC as part of its program, the PFP protocol employs (non-forced) high cadence cycling (HCC). However, this methodology has never been studied in a clinical trial.
Multiple small controlled trials have demonstrated that FHCC can ameliorate motor symptoms in individuals with PD as measured by the Unified Parkinson’s Disease Rating Scale-Part III and Timed up and Go.22–31 In FHCC, individuals with PD pedal with either a tandem co-rider or a motor providing external augmentation at a cadence of 80–90 revolutions per minute (rpm)—which is faster than most individuals would pedal on their own. Although the rate is augmented, cycling on either device is an active, not passive, activity. In comparing FHCC versus cycling at a self-selected cadence on a stationary indoor bicycle, most of the published literature has found that, despite similar cardiovascular exertion in the two modes, improved motor symptoms are only observed in the forced-cadence modality.26,29−31 One recent study did demonstrate gains in both forced and voluntary groups, but it was noted that the voluntary group self-selected to pedal at a cadence near the target achieved by the forced group.25
Despite the noted benefit of FHCC, the tandem or motor-augmented bicycle equipment required to implement this protocol in the community is not readily available or affordable. Based on his research of FHCC at The Cleveland Clinic, Jay Alberts, PhD along with Cathy Frazier, a person with Parkinson’s, launched The Pedaling for Parkinson’s™ (PFP) program,19 as an accessible and affordable alternative to FHCC. In PFP, individuals with PD are verbally coached to achieve moderate-exertion, high-cadence cycling (HCC) on solo-rider “spin” bikes. This differs from FHCC because there is no physical augmentation, only auditory and social cues encouraging participants to pedal at a high rate.
Although anecdotal evidence suggests participants in existing PFP programs enjoy the classes, dissemination of the intervention remains limited and the effectiveness of the program has not been established. Even though written instructions on how to run the PFP program are available, informal discussion with gyms that had already implemented a Parkinson’s cycling program revealed they had sought out additional instruction in starting their program. This additional support was obtained either directly from the volunteer coordinator running PFP, from a class participant who had taken part in a PFP elsewhere, or from a for-profit company not affiliated with PFP that charged a fee to support setting up a PD cycling program. Based on this information, we hypothesized that community gyms might be more willing to implement the program with additional support that would empower them to realize that they could implement the program without specialized knowledge of Parkinson’s Disease and within their existing infrastructure. We therefore developed an implementation strategy of enhanced multi-modal training coupled with ongoing local support to supplement the existing written PFP start-up materials.
We designed a type 3 hybrid trial to test our implementation strategy while gathering observational effectiveness data. Hybrid type 3 trials are best suited to interventions supported by strong “indirect” efficacy or effectiveness data whose rapid implementation is being encouraged by prevailing policy or culture.18 In the case of the PFP program, FHCC provides strong indirect evidence that HCC may be effective. Additionally, clinical guidelines already strongly recommend exercise for Parkinson’s and the PFP program has already been implemented at over 100 sites around the country.19
Consistent with the type 3 hybrid trial design, our primary outcomes were implementation measures and our secondary outcomes were exploratory effectiveness measures. We hypothesized that with our enhanced implementation strategy, PFP HCC could be implemented with high gym fidelity and participant adherence in a community-based setting and would be safe, affordable, and sustainable. If such implementation was achieved, we hypothesized HCC would be effective – ie would lead to motor, cognitive, and quality of life gains similar to those observed in controlled trials utilizing FHCC.