The trial, known as APPAHOCA-2, is described in BMC Geriatrics by Heidi Solem-Laviec of the Centre François Baclesse in Caen and her colleagues across two French centers. It is designed as a prospective, multicenter, open-label phase II study that will enroll 60 patients aged 65 and older who are scheduled for elective major cancer surgery or operations expected to carry high morbidity. Rather than waiting until complications appear, the investigators intend to measure whether daily supervised treadmill sessions can preserve or restore what geriatricians call functional fitness, using a well-established clinical yardstick: the six-minute walk test, or 6MWT. The distance a patient can cover in six minutes reflects the integrated performance of the heart, lungs, muscles, and nervous system, which is precisely why it has become a favored endpoint in studies of surgical recovery.

The logic of the design rests on a careful baseline. Before any operation takes place, each enrolled patient completes a comprehensive geriatric assessment during the month preceding surgery, and that visit includes a 6MWT measurement that captures the patient’s preoperative walking capacity. This pre-surgical value then becomes the reference point against which recovery is judged. The main endpoint of the trial is the proportion of patients who, at the time of discharge from the surgical ward, have regained their preoperative functional fitness as measured by the same test. In other words, the study does not ask whether patients simply improved over their hospital stay, but whether the intervention allowed them to climb back to their own personal starting line before going home.

The intervention itself is deliberately pragmatic. Unless a medical contraindication exists, patients in the trial will be offered one to two walking sessions per day on a treadmill, beginning the day after their operation. Each session is supervised by an Adapted Physical Activity Specialist, a professional trained to calibrate exercise intensity to fragile, recently operated patients, and the target duration ranges from six to thirty minutes. That flexibility matters. Early after abdominal, thoracic, or head and neck cancer surgery, a patient may manage only a few cautious minutes, while later in the admission the same person may tolerate a half hour of steady walking. The protocol’s designers have built that natural trajectory into the intervention rather than imposing a rigid dose that many frail patients could not achieve.

The scientific rationale comes in part from an earlier pilot study conducted by the same group, which showed that supervised treadmill walking in older cancer inpatients was feasible and could improve gait speed, with one important caveat: the benefit appeared in patients who were not malnourished. That finding highlights a biological reality that geriatric oncologists know well. Muscle recovery after surgery depends on an adequate supply of protein and energy, and in a patient whose nutrition is compromised, exercise can become a drain rather than a stimulus. The APPAHOCA-2 protocol therefore treats nutritional status as a critical variable, assessing it alongside sarcopenia, the age-related loss of skeletal muscle mass and strength that both cancer and major surgery can accelerate.

What makes the trial unusually comprehensive is the breadth of data it will collect. Assessments are scheduled at three points: before surgery, at hospital discharge, and at routine surgical follow-up visits 30 and 90 days after the operation. At each of these time points, the researchers will record levels of anxiety and depression, concerns about falling, cognitive function, nutritional and sarcopenia status, sleep complaints and changes in sleep-wake patterns, daytime activity, physical performance measures, and results from blood examinations. This multidimensional approach reflects a growing recognition in geriatric medicine that physical recovery cannot be separated from mental health, cognition, sleep, and metabolic state. A patient who walks farther but falls asleep poorly or becomes anxious about falling may not actually function better at home.

The hospital environment itself is a central character in this story. Clinical guidelines on postoperative rehabilitation have long advocated early mobilization, yet hospital wards are rarely designed to make walking safe and appealing for frail older adults. Corridors are busy, floors may be slippery, IV poles and monitoring equipment tether patients to their rooms, and nursing workloads leave little time for escorted walks. A walking treadmill, paradoxically, can offer a more controlled and secure environment than the ward corridor itself: handrails provide support, speed is adjustable and precisely known, and a specialist stands by to intervene. The APPAHOCA-2 investigators are essentially testing whether a piece of equipment more often associated with gyms can be safely redeployed to the surgical ward in the service of older cancer patients.

The study has cleared the standard regulatory hurdles that govern clinical research in France. It received ethical approval from the Comité de Protection des Personnes Ile de France I in December 2023, and the French Health Regulatory Authority, the ANSM, validated the investigation’s compliance with the European Union Medical Device Regulation. The trial is registered on ClinicalTrials.gov under identifier NCT06201884, with registration dated 2 January 2024, and the protocol has reached version 4.1 as of December 2025. Funding comes from the French Ministry of Health through the interregional hospital clinical research program, and the protocol itself was peer-reviewed by the funding body before the trial was granted support. The funding agency, the authors note, played no role in the design, conduct, or analysis of the study. All participants will receive an information file from their surgeons or anesthesiologists and must provide written informed consent before any study-related assessment begins.

The trial’s phase II designation signals its purpose: this is an effectiveness and feasibility study intended to establish whether the intervention works well enough to justify a larger definitive trial. Beyond the primary endpoint, the investigators plan to explore how the level of effectiveness relates to the number and duration of walking sessions patients actually complete during their recovery, a dose-response question that could shape how such programs are prescribed in the future. If patients who accumulate more minutes on the treadmill recover their walking capacity more reliably, that would support structured, supervised early mobilization as a standard component of postoperative care for older adults. If the relationship is weak or absent, the field will need to look elsewhere, perhaps toward nutritional optimization or other rehabilitation strategies.

For now, the value of APPAHOCA-2 lies in its clarity of purpose. It takes a problem that is easy to overlook, the quiet physical decline of older surgical patients during hospital stays, and subjects a simple remedy to rigorous measurement. The six-minute walk test, the geriatric assessments, the 90-day follow-up, and the careful tracking of sleep, mood, cognition, and nutrition together form a portrait of recovery that is far richer than length of stay alone could provide. As populations age and cancer surgery is performed increasingly on patients in their seventies and eighties, the question the French team is asking will only grow more urgent: can the hospital stay itself become part of the cure rather than an obstacle to it? The answer, the researchers hope, may begin with a few supervised steps on a treadmill the day after surgery.

Subject of Research: Early supervised treadmill walking to restore physical fitness in older inpatients recovering from cancer surgery

Article Title: Effectiveness of early supervised walking sessions on a walking treadmill in older inpatients after cancer surgery: study protocol for the APPAHOCA-2 trial

Article References: Solem-Laviec, H., Beauplet, B., Leconte, A., Coquerel, A., Demeude, F., Thuard, O., Ruet, A., Bastit, V., Babin, E., Varatharajah, S., Guilloit, J.-M., Fauvet, R., Waeckel, T., Perrier, J., Lequesne, J., & Clarisse, B. (2026). Effectiveness of early supervised walking sessions on a walking treadmill in older inpatients after cancer surgery: study protocol for the APPAHOCA-2 trial. BMC Geriatrics. https://doi.org/10.1186/s12877-026-08422-6

Image Credits: AI Generated

DOI: 10.1186/s12877-026-08422-6

Keywords: geriatric oncology, cancer surgery, treadmill walking, early mobilization, six-minute walk test, rehabilitation, sarcopenia, gait speed, older inpatients, clinical trial, physical deconditioning, APPAHOCA-2

The research, led by Giulia Casu and Massimiliano Pau of the University of Cagliari together with colleagues at the Regional Multiple Sclerosis Center of Sardinia, set out to answer a deceptively simple question: what actually happens to the quality of walking as fatigue accumulates over six minutes of continuous walking? While clinicians routinely use the six-minute walk test to gauge exercise capacity, the fine-grained temporal and spatial coordination of gait during this endurance challenge had been explored only through a single metric, leaving much of the picture unexamined.

To capture that picture, the team recruited 65 people with MS who could walk unaided for at least 200 meters, along with 43 age- and sex-matched unaffected individuals. Each participant wore eight miniaturized inertial measurement units sampling at 200 hertz, positioned on the lower spine, sacrum, thighs, tibiae, and forefeet. These wearable sensors tracked accelerations and angular velocities throughout the walk, allowing the researchers to reconstruct heel-strike events and joint-angle trajectories for hip and knee flexion-extension as well as ankle dorsi-plantarflexion. The 180-degree turns between consecutive 30-meter walking segments were carefully identified from pelvic yaw signals and excluded, ensuring that only steady-state straight-line walking entered the analysis.

On average, people with MS covered 477.95 meters over six minutes, significantly less than the 626.94 meters managed by unaffected participants, and both groups slowed progressively. But the most revealing findings came from the coordination metrics. The researchers computed the Phase Coordination Index, or PCI, a temporal measure that captures how accurately and consistently the left and right legs maintain ideal anti-phased stepping at 180 degrees. Healthy individuals typically score between 2 and 4 percent; lower values indicate better bilateral coordination. In this study, the MS group showed significantly higher PCI values than controls across the entire test, with a significant positive linear trend across the six minutes for both groups.

Strikingly, by the end of the test PCI had risen by about 53 percent in unaffected individuals but only 32 percent in people with MS. This counterintuitive pattern — the group with the disease deteriorating less — suggests a ceiling effect. People with MS started from a baseline of already-impaired coordination, constrained by reduced interhemispheric communication between the primary motor cortices, microstructural spinal cord damage, and degraded integrity of corticospinal, cerebellar, and brainstem pathways. With less adaptive capacity remaining, there was simply less room for further fatigue-driven decline. Their consistently slower walking speed may also have limited the range of available coordination strategies, restricting how much further measurable change was possible.

The study’s key methodological innovation was pairing this temporal metric with spatial measures derived from cyclograms — angle-angle diagrams that plot one joint’s motion against another across the gait cycle. From these closed curves, the team extracted geometric features including area, orientation, perimeter, and a dimensionless shape ratio. A perfectly symmetrical gait would collapse the inter-limb cyclogram onto a 45-degree line with zero area; larger areas and orientations deviating from that line signal asymmetry. For inter-joint analysis, hip-knee and knee-ankle cyclograms revealed how conjointly the adjacent joints modulate their movements through each stride.

The spatial data confirmed significant group differences at nearly every point measured. People with MS showed larger inter-limb cyclogram areas, orientations, and trend symmetry values at the hip and knee, indicating reduced symmetry, while their inter-joint cyclogram areas and perimeters for the hip-knee and knee-ankle couples were consistently reduced, reflecting a diminished dynamic range of motion and a reduced ability to modulate joint interactions across the phases of the gait cycle. Correlation analysis added clinical weight: within the MS group, PCI at minute one showed a moderate positive correlation with the MSWS-12 patient-reported walking scale, while hip-knee and knee-ankle cyclogram areas showed moderate-to-large negative correlations, linking laboratory measures of coordination directly to patients’ own perception of walking disability.

The temporal evolution of inter-joint coordination proved particularly instructive at the knee-ankle couple. In unaffected individuals, cyclogram area dropped significantly from the second minute onward; in people with MS, the reduction began a minute later. By the end of the test, however, the overall magnitude of change was similar in both groups. The authors interpret this as a possible convergence toward a shared, fatigue-driven motor strategy that prioritizes stability over flexibility at the distal joints. The ankle, central to propulsion and foot clearance, appears especially vulnerable to fatigue-related impairments such as reduced plantarflexion at push-off, which tightens its coupling with the knee. In contrast, the knee joint alone showed significant fatigue-related worsening only in unaffected individuals, possibly because compensatory strategies common in MS — increased reliance on proximal joints and muscular co-contraction to enhance stability — mask further deterioration at that level.

The authors acknowledge limitations, including a group size too small for stratified analyses of disability level, sex, or fatigability, and the fact that gait speed was not experimentally controlled, which means coordination changes over time cannot be fully disentangled from concurrent speed changes. The repeated turns demanded by the six-minute protocol may also have added sensorimotor load not directly quantified. Even so, the consistency of the baseline coordination deficits across both temporal and spatial domains, and their agreement quantitatively with values reported in earlier independent studies, underscores the robustness of the approach.

The clinical implications reach well beyond the laboratory. Because baseline coordination deficits and fatigue-related changes followed dissociable patterns, rehabilitation strategies for MS may need to target coordination quality and adaptability explicitly, not merely walking endurance. The sensitivity of cyclogram-based measures to knee-ankle coupling suggests that distal coordination is a promising target for interventions aiming to improve propulsion efficiency and stability during prolonged walking. And because temporal and spatial metrics captured joint- and domain-specific behaviors that a single index missed, the multimodal framework developed here offers clinicians a more complete toolkit for tailoring rehabilitation, monitoring therapeutic response, and identifying patients who rely on compensation rather than genuine adaptive motor control — a step toward better walking performance, reduced fatigability, and greater independence in daily life for people living with MS.

Subject of Research: Temporal and spatial gait coordination changes during the six-minute walk test in people with multiple sclerosis, measured with wearable inertial sensors.

Article Title: Changes in temporal and spatial gait coordination during the six‑minute walk test in people with multiple sclerosis

Article References: Casu, G., Lostia di Santa Sofia, E., Leban, B., Inglese, C., Coghe, G., Frau, J., Cocco, E., & Pau, M. (2026). Changes in temporal and spatial gait coordination during the six‑minute walk test in people with multiple sclerosis. Medical & Biological Engineering & Computing. https://doi.org/10.1007/s11517-026-03678-x

Image Credits: AI Generated

DOI: 10.1007/s11517-026-03678-x

Keywords: multiple sclerosis, gait coordination, six-minute walk test, phase coordination index, cyclograms, inertial measurement units, gait analysis, fatigue, rehabilitation, biomechanics, mobility, neurology