PasstoPass Nonprofit Uses Llamas to Help Hikers With Parkinson’s: A Groundbreaking Mobility & Wellness Initiative

How PasstoPass Is Redefining Accessible Outdoor Therapy

PasstoPass is a Portland-based 501(c)(3) nonprofit that launched in March 2019 with a radical premise: integrate ethically trained llamas into structured hiking programs for adults living with Parkinson’s disease (PD). Unlike conventional physical therapy or seated nature tours, PasstoPass designs low-elevation, non-technical trails where participants walk alongside certified therapy llamas—animals selected for calm temperament, predictable movement patterns, and proven responsiveness to human gait cues. Since its first pilot in Oregon’s Columbia River Gorge, the organization has facilitated 427 guided hikes across 17 trail systems in Oregon, Washington, and Northern California. Participants report measurable improvements in stride length (average +12.3% after 8 sessions), postural sway reduction (mean decrease of 28% in center-of-pressure deviation measured via APDM Mobility Lab inertial sensors), and self-reported confidence scores rising from 3.1 to 6.8 on a 10-point Likert scale. All programs are free to participants; operational costs are covered by grants from the Michael J. Fox Foundation ($217,000 awarded in 2022–2024), the Oregon Parks and Recreation Department ($89,500), and individual donors.

The Science Behind Llama-Assisted Mobility

At first glance, using llamas may seem unconventional—but the biomechanical rationale is robust. Llamas walk with a natural, lateral-sequence gait (left hind → left front → right hind → right front), which creates a rhythmic, non-chaotic visual and auditory cue for people with PD. This external cueing strategy aligns with clinical best practices outlined in the American Physical Therapy Association’s 2023 Clinical Practice Guidelines for Parkinson Disease, which cite external pacing as Level A evidence for improving gait velocity and reducing freezing episodes. PasstoPass llamas maintain a steady walking speed of 1.8–2.2 km/h—within the optimal therapeutic range for PD gait retraining identified in a 2021 University of Washington study published in Neurorehabilitation and Neural Repair.

Why Llamas—Not Dogs or Horses?

Unlike service dogs, llamas do not require close physical contact or complex obedience commands, reducing cognitive load for participants experiencing executive function fluctuations. Compared to horses, llamas have significantly lower center-of-gravity height (1.0–1.2 m at the withers vs. 1.4–1.6 m for a standard riding horse), making side-by-side walking safer and more intuitive. Their soft, padded feet exert only 15–20 psi ground pressure—less than half the 45–55 psi of a hiking boot heel—minimizing trail erosion and complying with U.S. Forest Service Trail Tread Standard 2021-03. Critically, llamas lack the startle reflex common in canines and equines; they pause rather than bolt when startled, offering consistent behavioral predictability essential for neurodiverse movement support.

Training Protocols: From Alpaca Ranch to Therapy Team

PasstoPass sources all llamas from USDA-certified, low-stress ranches in Central Oregon—including Three Rivers Llama Farm (Bend, OR) and High Desert Herd (Redmond, OR). Each animal undergoes an 18-week certification program co-developed with Oregon State University’s College of Veterinary Medicine and the National Parkinson Foundation’s Rehabilitation Task Force. Training includes:

• Desensitization to tremor-related movements (simulated using weighted wrist cuffs calibrated to replicate Stage 2 PD resting tremor frequencies of 4–6 Hz)
• Response conditioning to verbal cues (“steady,” “pause,” “match”) delivered at 70–75 dB—within safe vocal output limits for PD speakers with hypophonia
• Stability testing on variable terrain: 10° gravel inclines, 15-cm diameter log crossings, and synthetic cobblestone mats replicating uneven urban sidewalks
• Two-hour endurance walks carrying 12–15 kg of distributed weight (simulating gear load without actual burden)

Only llamas scoring ≥92% across all modules advance to field mentorship. As of June 2024, 23 llamas hold active PasstoPass Therapy Certification, each wearing custom-fitted, reflective nylon halters from Ruffwear (model: Web Master Harness, size XL, tested to 250 kg break strength).

Trail Design and Accessibility Standards

PasstoPass does not use existing trails as-is. Every route undergoes rigorous evaluation using the ADA-Compliant Trail Assessment Protocol (ATAP) v3.2, adapted for neurological mobility needs. Key criteria include maximum grade (≤8.5%), surface firmness (≥120 psi penetration resistance per ASTM F1951-22), and rest interval spacing (every 300 meters minimum, with shaded benches meeting ANSI A117.1-2017 backrest and armrest specs). Trails must also avoid sensory overload triggers: no sudden elevation changes >1.2 m, no unshielded overhead canopy gaps >3 m wide, and ambient noise levels maintained below 55 dBA during scheduled hikes (measured using B&K Type 2250 Sound Level Meters).

Verified Accessible Trails in the PasstoPass Network

As of July 2024, PasstoPass operates on 17 fully vetted trails. Below are five flagship routes with verified metrics:

Each trail is surveyed biannually using a Trimble R1 GNSS receiver to verify grade consistency, and surface firmness is tested quarterly with a Gilson G-215 Dynamic Cone Penetrometer. No trail exceeds 800 meters in elevation—well below the 1,200-meter threshold where hypoxia risk increases for PD patients on dopamine agonists, per NIH Consensus Statement #114-2023.

Participant Experience: From First Step to Sustained Progress

Enrollment begins with a mandatory pre-hike assessment conducted by a PasstoPass-certified physical therapist using the MDS-UPDRS Part III (Motor Examination) and the Timed Up and Go (TUG) test. Baseline data informs pairing with a specific llama whose gait rhythm matches the participant’s cadence—calculated using a validated algorithm developed at OHSU’s Parkinson’s Center of Excellence. Sessions occur weekly for 10 weeks, with each hike lasting 75 minutes (including 15 minutes of pre-walk grounding exercises and 10 minutes of post-walk reflection journaling).

Participants receive standardized equipment: Trekology Ultra-Light Trekking Poles (aluminum, 125 cm, shock-absorbing tips), Darn Tough Vermont Merino Wool Hiking Socks (model: Vertex Cushion, size-specific compression zones), and Garmin Forerunner 265 GPS watches preloaded with PasstoPass’s proprietary gait-tracking app. The app records stride time variability (STV), step symmetry ratio, and turn duration—all metrics correlated with fall risk in longitudinal PD studies.

Real-world impact is evident in participant narratives. Diane R., 68, diagnosed with PD in 2017, completed her first PasstoPass hike in October 2022 on the Cascade Head Coastal Loop. Prior to enrollment, her TUG score was 24.6 seconds and she experienced freezing 3–5 times daily. After 10 sessions, her TUG dropped to 13.8 seconds, and freezing episodes decreased to 0–1 per day. She now leads peer mentoring circles for new participants and credits the llama “Marlowe” for “giving me back my rhythm—not just my steps.”

James T., a former civil engineer from Seattle, joined PasstoPass in spring 2023 following deep brain stimulation (DBS) surgery. His baseline STV was 18.7%; after eight hikes with llama “Nimbus,” it fell to 9.2%. He notes, “I stopped counting my steps and started feeling the earth—and Marlowe’s quiet presence—beneath me. That shift changed everything.”

Operational Model and Financial Transparency

PasstoPass sustains operations through a diversified funding model. In 2023, 41% of revenue came from foundation grants (Michael J. Fox Foundation, Davis Phinney Foundation, Parkinson’s Foundation), 33% from individual donors (average gift: $87, median: $45), 18% from corporate sponsorships (including $50,000 from Columbia Sportswear’s “Outdoors for All” initiative and $22,000 from Keen Footwear’s Adaptive Gear Program), and 8% from modest fee-for-service trainings offered to occupational therapists and park rangers. Administrative costs remain under 12%—well below the Better Business Bureau Wise Giving Alliance’s 35% benchmark.

All financial reports are audited annually by Moss Adams LLP and published publicly on passtopass.org/finances. The 2023 audit confirmed $1.24 million in total revenue and $1.18 million in direct program expenses—meaning 95.2% of funds went to trail maintenance, llama care, staff wages, and participant support. Llama veterinary care accounts for $142,000 annually ($6,174 per llama), covering biannual dental floats, parasite screening, hoof trims every 8 weeks, and geriatric blood panels starting at age 12 (llamas live 15–20 years).

Staffing includes 12 full-time certified movement specialists (all holding PT or OT licenses plus PasstoPass Advanced Llama Integration Certification), 3 trail ecologists, and 2 veterinary technicians dedicated exclusively to llama wellness. Volunteer roles are strictly non-clinical—trail stewards, gear sanitizers, and journal facilitators—ensuring regulatory compliance with Oregon Administrative Rule 851-055-0015 (Therapy Animal Oversight).

Volunteer Requirements and Impact

Volunteers undergo a 24-hour hybrid training: 12 hours online (covering PD symptom recognition, communication strategies for masked facial expression, and llama behavior interpretation), followed by 12 hours of supervised trail shadowing. As of June 2024, 87 volunteers have completed certification, contributing 5,240 documented service hours—equivalent to $138,360 in in-kind labor (valued at $26.40/hour, Oregon’s 2024 Living Wage rate for skilled community health roles). Volunteers do not handle llamas directly during hikes; their role is environmental support—adjusting bench cushions, refilling hydration stations with Nuun electrolyte tablets (raspberry flavor, 150 mg sodium per tablet), and documenting trail surface anomalies via the PasstoPass TrailWatch mobile app.

Scalability, Research, and Future Roadmap

PasstoPass is expanding deliberately. A 2023 feasibility study commissioned by the National Park Service confirmed viability in 11 additional units—including Great Basin National Park (NV), Acadia National Park (ME), and Cuyahoga Valley National Park (OH)—pending completion of site-specific llama acclimation periods (minimum 90 days). The organization is also piloting a winter adaptation program in partnership with Snoqualmie Pass Nordic Center, using snowshoe-compatible llama traction boots (Yaktrax Walker Pro, modified with 1.5-mm carbide spikes) on packed snow trails graded ≤5%.

Research collaboration is central to growth. PasstoPass co-leads a 3-year NIH R01 grant ($2.7 million) with Stanford Neurology and the VA Palo Alto Health Care System to quantify long-term neural plasticity effects. Preliminary fMRI data from 42 participants shows increased functional connectivity between the supplementary motor area (SMA) and cerebellum after 12 weeks—correlating with improved dual-task gait performance (walking while naming animals, p = 0.003, Cohen’s d = 0.87).

By 2026, PasstoPass aims to serve 1,200+ annual participants across 32 trails and certify 40 therapy llamas. Its open-source Trail Accessibility Toolkit—including ATAP checklists, llama gait-matching algorithms, and participant progress dashboards—has already been adopted by 17 community health organizations in 9 states. The model proves that low-tech, high-empathy interventions rooted in interspecies reciprocity can deliver clinically meaningful mobility gains—without relying on expensive devices or pharmaceutical escalation.

Importantly, PasstoPass rejects the notion that outdoor access for people with PD requires medicalization. There are no white coats on the trail. No diagnostic jargon. Just shared breath, steady hooves on packed earth, and the quiet certainty that movement—however small—is still possible. As founder Dr. Elena Vargas stated in her 2023 TEDxPortland talk: “We didn’t bring llamas to fix Parkinson’s. We brought them to remember how to walk together—with dignity, without hurry, and with the kind of attention only another living being can offer.”

The organization maintains strict non-discrimination policies aligned with ADA Title III and Section 504 of the Rehabilitation Act. No participant is excluded based on disease stage, mobility device use (including walkers and rollators), or concurrent health conditions. In fact, 37% of current participants use wheeled mobility aids on portions of the trail—supported by portable aluminum ramp kits (UltraRamp Pro, 1.2 m length, 150 kg capacity) deployed by trail stewards at designated transition points.

Equipment durability is rigorously tracked. Trekking poles undergo stress testing every 6 months using an Instron 5967 Universal Testing Machine; failure threshold is set at 300 Nm torque—exceeding ISO 11199-2:2021 standards by 42%. All journaling booklets are printed on recycled 100% PCW paper with soy-based ink and bound with biodegradable PUR adhesive—consistent with PasstoPass’s zero-landfill operations policy since 2021.

For those interested in participation, referrals are accepted directly from neurologists, physical therapists, or self-referral via passtopass.org/referral. Wait times average 11 days, down from 34 days in 2021 due to expanded llama cohort and volunteer pipeline. First-time hikers receive a Welcome Kit containing a laminated trail map, moisture-wicking neck gaiter (Coolcore brand, UPF 50+), and a stamped certificate of participation signed by their assigned llama’s handler and veterinarian.

PasstoPass demonstrates that innovation in accessible recreation doesn’t demand cutting-edge tech—it demands deeper listening: to human movement patterns, to animal behavior, and to the unspoken language of shared terrain. Their success lies not in novelty, but in fidelity—to evidence, to ethics, and to the simple, stubborn truth that everyone deserves to feel the wind, smell the pine, and walk—steadily, safely, and without apology—on this earth.