Exercise and Rehabilitation for PLS

Exercise and rehabilitation in PLS are not about pushing through to maintain fitness in the conventional sense. They are about managing spasticity, preserving functional movement, reducing fall risk, and maintaining the muscle tone and flexibility that spastic disease will otherwise rob you of. The evidence supports staying active — carefully, with guidance, and adjusted as the disease evolves.

What the evidence actually says

The Cochrane review on therapeutic exercise in ALS and motor neuron disease (2019), published in PMC, found low-to-moderate quality evidence that aerobic and resistance exercise may slow decline in functional scales like the ALSFRS-R. The review concluded that exercise is likely safe when properly prescribed, but that clinical benefit remains incompletely established, and that exercise should be individualized and moderate in intensity.

This is honest — not a ringing endorsement, not a dismissal. The APTA (American Physical Therapy Association) Degenerative Diseases SIG 2022 fact sheet is more specific: it states that moderate aerobic exercise and resistance training are generally considered safe in early-to-mid stage motor neuron disease, and that exercise prescriptions must be individualized and adjusted for disease stage.

For PLS specifically, the evidence base is smaller than for ALS (because PLS is rarer), but the underlying physiology provides some guidance. PLS is a pure upper motor neuron disease — muscles are not denervated, they are under abnormal tonic excitation. This means muscle strengthening is physiologically meaningful in a way it may not be in lower motor neuron disease. The risk of overuse weakness that is a concern in ALS — where already-denervated muscle fibers may be damaged by heavy exercise — is less central to PLS management.

The Spastic Paraplegia Foundation, which covers PLS and hereditary spastic paraplegia, recommends physical therapy and exercise to maintain strength, balance, and walking endurance — with appropriate safety precautions given the elevated fall risk in spastic gait.

Physical therapy: what to work on and why

Physical therapy for PLS is distinct from general fitness programming. A PT experienced in upper motor neuron conditions (including PLS, HSP, and spastic cerebral palsy) understands the difference between a muscle that is weak and one that is hypertonic, and knows that the primary therapeutic targets are different.

Stretching: aggressive and consistent

Spastic muscles chronically shorten. If this is not countered with regular stretching, the result is contractures — permanent shortening of the muscle-tendon unit that restricts joint movement, causes pain, and cannot be fully reversed. Preventing contractures is one of the most important goals in PLS rehabilitation, and it requires consistent daily stretching rather than occasional sessions.

Key muscle groups to prioritize in PLS stretching programs include the calf complex (gastrocnemius and soleus — tight calves drive the toe-catching gait pattern), hamstrings, hip flexors and adductors, and often the chest and shoulder girdle when arm function is affected. Your PT will design a home program tailored to where your spasticity is most pronounced. Splitting this into morning and evening sessions makes it more sustainable than trying to do everything at once.

Strengthening: gentle and targeted

Strengthening in PLS is a more nuanced goal than in people with weakness-dominant neuromuscular disease. The available muscle strength is functionally reduced by the overlay of spasticity — the muscles work against each other. Targeted strengthening of antagonist muscles (those opposing the spastic ones) can help create more balanced tone around joints.

Core strengthening is particularly useful for supporting posture during gait and reducing the compensatory sway that increases fall risk. Upper extremity strengthening helps maintain independence in daily tasks. The key is to avoid exercise that causes prolonged fatigue extending into the next day — that is a sign of overexertion.

Gait training and balance

According to one clinical survey, 76% of PLS patients require gait assistive devices during their disease course — yet only 24% receive formal physical therapy. This is a significant gap. Gait training in PLS helps patients maintain a safer and more efficient walking pattern for longer, and when assistive devices are needed, PT ensures they are prescribed correctly and used properly.

Balance training is essential given the combination of spastic lower limbs, slowed reflexes, and occasional foot-drop pattern in PLS. Falls are a genuine safety risk. Balance exercises, practiced within a safe environment (near a wall or with a therapist), build proprioceptive and reactive capacity that reduces fall frequency.

The Lokomat case study

A 2021 case report published in Innovations in Clinical Neuroscience describes the use of the Lokomat-Pro — a robotic exoskeleton gait trainer — in a patient with PLS. The Lokomat supports body weight on a treadmill and guides the legs through a controlled walking pattern with consistent, repetitive input.

In this PLS patient, conventional physiotherapy alone had not produced significant functional improvement. Adding robot-aided gait training to the conventional PT program produced significant gains in walking speed, balance, lower limb strength, and spasticity measures. The combined approach was clearly superior.

This is a single case — PLS-specific evidence is limited by the rarity of the disease. But the result aligns with what is known about neuroplasticity and repetitive task practice in upper motor neuron conditions: intensive, patterned movement provides the motor system with input that promotes functional reorganization. The Lokomat produces a quality and consistency of gait input that would be exhausting and practically impossible to maintain through conventional PT alone.

Lokomat systems are available at some larger rehabilitation and academic medical centers. If access to robot-aided gait training interests you, ask your neurologist or physiatrist for a referral to a center with this capability.

Aquatic therapy

Warm water immersion directly reduces muscle tone — the heat relaxes spastic muscles in a way that is difficult to replicate on land, providing a window of function that many PLS patients do not experience in dry-land therapy. The buoyancy reduces the physical demand of movement and eliminates fall risk, allowing exercise that would be unsafe or too effortful on dry land.

Aquatic therapy programs run by physical therapists experienced in neurological conditions provide gait practice, strengthening, stretching, and balance work in this environment. Many people with PLS report aquatic therapy as the most functionally productive and physically comfortable exercise they do. It requires access to a pool and ideally a PT-led session, but the investment is typically worth it.

Occupational therapy: adaptive strategies and energy management

Occupational therapy (OT) addresses how you perform daily tasks — not just whether you can perform them, but whether you can perform them safely, sustainably, and with appropriate adaptive strategies when the disease makes standard approaches impractical.

In PLS, OT focuses on:

• Home assessment and modification — identifying fall hazards, recommending grab bars, ramp installations, and bathroom adaptations
• Adaptive equipment for daily tasks — modified utensils, jar openers, button aids, reachers, and other tools that reduce the effort required for self-care
• Ergonomic modification of work and hobby environments to reduce fatigue and strain
• Energy conservation planning — structuring the day to match demanding tasks with peak energy windows
• Upper extremity function — when arms and hands are affected by spasticity, OT provides targeted strategies to maintain function longer

Energy conservation: the Four Ps

Energy conservation is an OT approach to managing the fatigue that accumulates when all physical activity requires more effort than it should. A randomized controlled trial of energy conservation management in motor neuron disease (published in SAGE 2017) found significant improvements in fatigue outcomes. A separate systematic review of energy conservation management (ECM) showed it increased participation in daily activities.

The core framework is the Four Ps:

• Prioritize — identify which activities genuinely matter and which can be reduced or eliminated
• Plan — schedule demanding tasks during your best-energy times of day; avoid clustering multiple effortful activities
• Pace — alternate activity and rest rather than pushing through until exhausted; take breaks before you need them
• Position — use positioning (sitting versus standing, supported versus unsupported) to reduce the energy cost of tasks

ALS New Mexico's 2024 energy conservation guide for motor neuron disease provides practical application of these principles in daily life — your OT can walk through its application to your specific activities.

Understanding fatigue in PLS

Fatigue in PLS is not simply about being tired after exercise. There are at least two distinct types:

Primary fatigue is neurological in origin — caused by the extra cortical and spinal effort required to move spastic muscles. Every step taken against your own tone is more metabolically and neurologically demanding than a step without that resistance. This fatigue cannot be fully overcome by rest or fitness; it requires management through energy conservation and activity modification.

Secondary fatigue comes from downstream effects: disrupted sleep (often from nocturnal spasms or discomfort), depression, medication side effects (baclofen and tizanidine are both sedating), and deconditioning from reduced activity levels. These secondary sources are often more modifiable — treating the sleep disruption, addressing the depression, optimizing medication dosing, and maintaining appropriate physical activity all reduce secondary fatigue.

Working with a PT who understands UMN disease

Not all physical therapists are equally equipped to work with PLS. A PT who primarily sees post-surgical orthopedic patients or sports injuries may not be familiar with the specific demands of upper motor neuron disease — the primacy of stretching over strengthening, the fatigue management principles, the fall risk patterns of spastic gait, or the way exercise prescription needs to shift as the disease evolves.

When looking for a PT, ask specifically about experience with neurological patients — ideally with UMN conditions such as spastic cerebral palsy, hereditary spastic paraplegia, or multiple sclerosis as well as ALS and PLS. ALS clinics often have PT staff or affiliates with direct MND experience. Your neurologist's referral is worth asking about specifically: "Can you refer me to a PT with experience in upper motor neuron disease?"