Cycling Adaptation: From Bedridden to Cross-Country, and What Transfers to MS

Source article: A Mysterious Illness Left Him Bedridden At 51. Now He Is Riding An E-Bike Across America For The Second Time (The Cycling Week, July 28, 2026).

This is a summary of that piece, then an expansion from small-fiber peripheral neuropathy into multiple sclerosis. The transfer is not one-to-one. The mechanisms overlap in places and diverge in others. That distinction is the point.

The case

Gregory Maassen was 51, a global-development executive who lived on travel and long hours. After walking into a nest of ticks on a hike in South Africa in 2017, a burning sensation started near the top of his left arm and, within a month, ran from his ears to his feet. He spent nearly a year barely able to leave bed. Two years of specialists produced no name until Johns Hopkins diagnosed small fiber peripheral neuropathy.

Dr. Ahmet Hoke (Merkin Peripheral Neuropathy and Nerve Regeneration Center) gave him a prescription that sounded like a joke: ride a bike. Every day. Plus resistance work and a floor of about 30 minutes of daily movement.

Hoke's public position is blunt: for most peripheral neuropathies, exercise is the only intervention with a signal on skin biopsies that nerves can regenerate. Drugs do not currently rebuild damaged sensory fibers. A 2023 Frontiers systematic review concluded that early, active physical programs promote axonal regeneration and reduce maladaptive nerve responses. The human trial base is thinner than the animal literature. Hoke is prescribing from the best available signal, not from a finished proof.

Maassen could barely stand. He did not return on a race bike. He used an e-bike. The science of regeneration does not care whether a motor is helping. It cares about volume, duration, and showing up on bad days. Muscle contraction, blood flow, and neurotrophic factors (including work out of Hopkins neurology in 2014 linking activity to nerve-related growth factors) happen with or without assist.

That is the mechanism the article keeps returning to: the e-bike removed the failure mode. On a high-pain day a road bike keeps you in bed. An e-bike gets you out the door. Consistency is the stimulus. Intensity is optional.

Results, as reported:

• 2022: Washington, D.C. to San Francisco on the Lincoln Highway. 4,685 miles. First person reported to ride an e-bike coast to coast in the U.S.
• 2026: West Palm Beach to Los Angeles. 5,800+ miles over five months, in partnership with the Merkin center.
• He is 55. Nerves are not fully restored. Pain still returns. Mobility, sleep, and daily function improved enough that a life in bed is no longer the baseline.
• Even with assist he was burning on the order of 2,500 calories a day on the long routes and going through multiple batteries.

Yellow wooden clogs on the rear rack are a Dutch joke and a conversation engine. Awareness work is the second product of the ride.

Benefits the article actually claims

Strip the narrative and the claimed benefits are:

1. Nerve-fiber regeneration signal. Exercise is currently the only intervention with biopsy-level evidence of small-fiber recovery in this class of neuropathy. Not a cure. A dose-dependent stimulus.
2. Volume over heroics. Regeneration and the broader endurance adaptations (mitochondria, capillaries, cardiac stroke volume, tendon collagen) reward repeated appropriate load, not suffering theater.
3. Adherence on bad days. Assist is not a moral category. It is a compliance tool. If the alternative is zero minutes, assist wins.
4. Low-impact consistency across decades. Cycling lets people stack years of stimulus after running becomes a joint gamble.
5. Bridge back into sport. Riders who drop out because of back pain, numb hands, post-concussion limits, or a knee that fails on climbs can often still turn the cranks with assist.
6. Function and sleep, not just miles. The Brain & Life / AAN reporting cited in the article is about daily life, not Strava.

Two caveats the original piece already owns:

• Small-fiber neuropathy after a discrete immune hit is not diabetic neuropathy, not chemo neuropathy, and not handlebar-pressure numbness (usually a fit problem).
• The regeneration literature is still animal-heavy. Human trials exist. They are not definitive for every patient.

What does not transfer blindly to MS

Multiple sclerosis is a central nervous system disease: inflammation, demyelination, axonal loss in brain and spinal cord. Maassen's injury was peripheral small fibers after an immune reset. Different tissue. Different time course. Different failure modes.

MS also has heat sensitivity (Uhthoff), fatigue that is not ordinary tiredness, balance risk, and a disability range from mild relapsing disease to wheelchair-level progressive disease. "Ride across America" is not a protocol. It is a proof that a body can still load when the right machine removes the drop-out condition.

Do not treat N=1 as population truth. Treat it as a existence proof that assisted cycling can restore a training stimulus when unassisted cycling cannot.

What the MS literature actually supports

Expert panel, no cheering section.

Neurology / MS rehab (Mayo, Cleveland Clinic, guideline authors): Exercise is not optional color. Disease-modifying drugs reduce inflammatory attacks. They do little to reverse accumulated disability. Aerobic work is one of the few tools with repeated signals on fatigue, walking speed, pain interference, mood, and cardiorespiratory fitness. Mayo's public line: daily aerobic work on the order of 30 minutes, modified for balance and heat. Recumbent or stationary bikes are explicitly named when standing balance is the limiter.

Cleveland Clinic pilot (12-week moderate-to-high intensity cycling, forced-rate and voluntary-rate): Improvements in physical and total fatigue (MFIS; the total drop met a minimally clinically important difference), pain intensity and interference (PROMIS-29), and walking speed (0.61 to 0.68 m/s). Six-minute walk improved modestly. Forced-rate cycling let a higher-disability participant (EDSS 6.5) hit intensity that voluntary cycling did not. Small sample. Pilot. Directionally consistent with larger exercise-in-MS reviews.

Guidelines (harmonized MS exercise prescriptions, ESSA and related reviews): For mild-to-moderate disability (roughly EDSS ≤ 6.5): aerobic work 2–3 days/week, 10–30 minutes to start, moderate intensity (about 40–60% VO2max or RPE 11–13); resistance 2–3 days/week. Cycle ergometry is a first-line modality because it is seated, doseable, and does not demand gait. Advanced prescription for people already training: more days and higher intensity. Exercise does not appear to raise relapse risk in pooled data; some older reviews show slightly lower relapse rates in exercisers than controls. That is association plus small trials, not a disease-modifying claim.

Mechanistic camp (reviews arguing neuroprotection): Exercise can raise BDNF, lower some pro-inflammatory cytokines, and in animal models push oligodendrocyte-lineage cells. Human imaging and atrophy outcomes are mixed. High-intensity aerobic work has improved fitness and, in at least one trial, lowered relapse rates without changing the primary brain-atrophy endpoint. Plasticity and remyelination talk is biologically plausible and not yet a clinical guarantee.

Severe disability / FES cycling camp: Once walking needs two aids or a chair (EDSS ~6.5+), voluntary outdoor cycling is often off the table. Functional electrical stimulation cycling is a different machine: stimulators fire the legs on a recumbent ergometer. Feasibility is good. Fatigue and pain often improve. Cognition (processing speed) has shown clinically meaningful change in small RCTs. Walking outcomes are inconsistent. A 2026 Johns Hopkins-area RCT in secondary progressive MS found no walking difference between FES and passive cycling over 12 weeks. Small N, short duration, higher baseline disability. Read that as "do not oversell walking restoration," not as "do nothing."

Skeptical methodologist: Most cycling-in-MS studies are small, short, and heterogeneous. Forced-rate vs voluntary, FES vs passive, outdoor vs ergometer, relapsing vs progressive — these are not the same intervention. Publication bias exists. Heat, fall risk, and post-exertional symptom spikes are real. "Exercise is medicine" is true as a slogan and sloppy as a prescription. Dose, modality, and exit ramps matter.

Where Maassen and MS rhyme

• The limiter is often getting the session to happen, not the theoretical max wattage. Assist, recumbent geometry, indoor trainers, and FES are all versions of the same idea: keep the stimulus alive when the classic road bike is a non-starter.
• Consistency beats intensity theater. MS guidelines start at two or three modest sessions. Maassen's neurologist started at daily movement he could actually complete.
• Cycling is joint-sparing and balance-optional. That is why it shows up in both stories.
• Function first. Fatigue, pain interference, gait speed, sleep, and "can I leave the house" are the outcomes that change a life. Continent crossings are marketing and meaning. They are not the dose.

Where they do not rhyme

• Peripheral small-fiber regeneration after a monophasic immune hit is not remyelination of a brain lesion.
• MS can worsen with overheating. Outdoor summer centuries are a different risk profile than neuropathy training.
• Progressive MS can keep taking tissue while you train. Exercise is disease management and capacity building. It is not a promise the MRI stays still.
• E-bike across America requires enough residual motor control, autonomic stability, and logistics to live on a bike for months. Most people with MS who would benefit from cycling will benefit from a trainer in a cool room three times a week.

Practical translation

If the goal is adaptation — nerves, muscle, mitochondria, mood, gait — the hierarchy is:

1. Medical clearance and an honest map of heat, balance, and fatigue patterns.
2. A bike you will use on a bad day: e-assist, recumbent, stationary, or FES if voluntary drive is gone.
3. Dose you can repeat: start closer to the guideline floor (20–30 minutes, 2–3 days) than to a tour.
4. Cool environment. Pre-cool, ice vest, indoor sessions if Uhthoff is in play.
5. Strength work on the same weekly skeleton. Aerobic-only is incomplete.
6. Track function (fatigue scores, walk speed, sleep, next-day crash) harder than miles.
7. Stop treating assist as cheating. The tissue does not grade your virtue.

Critical review

The Cycling Week piece is well-sourced for a feature: named neurologist, named center, named review, named distances, named second-tour partnership. It is still a feature. It leans on one extraordinary adherent. That is allowed as illustration. It is not allowed as proof that e-bikes regenerate nerves in every neuropathy or in MS.

The MS expansion above is stronger on fatigue, fitness, and gait than on "exercise repairs MS lesions." The strongest claim you can defend in 2026: appropriately dosed cycling is safe for most people with mild-to-moderate MS, improves symptoms that actually disable people, and is one of the few non-drug inputs with a repeatable signal. For severe MS, seated and stimulated cycling is feasible and sometimes helps symptoms; walking restoration is not a reliable headline.

Maassen's real contribution is not the mileage. It is the design pattern: when the body will not accept the traditional implement, change the implement before you abandon the stimulus.