Aquatic Treadmill Training After Stroke

Regaining walking ability is one of the primary rehabilitation goals after stroke. While conventional gait training remains the standard of care, aquatic treadmill training after stroke is gaining attention as a promising alternative. A 2026 feasibility study investigated whether four weeks of aquatic treadmill training could improve both gait performance and cerebrovascular function in community-dwelling stroke survivors.

Why use an aquatic treadmill after stroke?

Many stroke survivors experience reduced walking capacity, impaired balance and fear of falling. These limitations often make conventional treadmill training challenging.

Walking in water combines the benefits of treadmill gait training with the supportive properties of water. Buoyancy reduces weight-bearing, hydrostatic pressure improves circulation and stability, while water resistance provides gentle strengthening throughout the walking cycle. Together, these properties allow patients to practise gait in a safer and more comfortable environment.

Study design

Six community-dwelling stroke survivors participated in a four-week aquatic treadmill programme.

The intervention included:

• 3 supervised sessions per week
• 20–30 minutes per session
• Water temperature of approximately 32°C
• Water depth at the level of the iliac crest
• Low-intensity walking with gradual progression based on perceived exertion

Researchers evaluated both gait performance and cerebrovascular responsiveness before and after the intervention.

Excellent feasibility and patient adherence

One of the strongest findings was the excellent feasibility of the programme.

The study reported:

• 97% attendance (70 of 72 planned sessions)
• No participant withdrawals
• No adverse events
• High participant satisfaction and motivation

These findings suggest that aquatic treadmill training is well tolerated, even in individuals living with chronic stroke several years after the event.

Improvements in walking performance

Several participants demonstrated meaningful improvements in gait following only four weeks of training.

Faster walking speed

Walking speed increased in the 10-Metre Walk Test, with two participants achieving clinically meaningful improvements exceeding 0.20 m/s.

Improved walking speed is closely associated with greater functional independence after stroke.

Greater walking endurance

Walking distance during the 6-Minute Walk Test improved by an average of 38 metres.

Several participants exceeded the threshold for clinically meaningful improvement, while two individuals achieved substantial gains of more than 140 metres.

Improved step length

Participants also demonstrated improvements in paretic step length, indicating better gait symmetry and more efficient walking mechanics.

These changes may contribute to safer and more confident walking during daily activities.

Potential improvements in brain health

A unique aspect of this study was its investigation of cerebrovascular function.

Researchers measured cerebrovascular reactivity, an indicator of how well blood vessels in the brain respond to changes in carbon dioxide.

Following aquatic treadmill training:

• cerebrovascular responsiveness increased by 44% in the stroke-affected hemisphere,
• and by 48% in the unaffected hemisphere.

Although these improvements did not reach statistical significance because of the very small sample size, the magnitude of change was considered promising and warrants further investigation.

Why aquatic treadmill training may be effective

The authors describe several mechanisms that may explain these improvements.

Increased cerebral blood flow

Water immersion increases central blood volume and cardiac output, which may enhance blood flow to the brain during exercise.

Improved cerebral perfusion may stimulate beneficial vascular adaptations important for long-term brain health.

Reduced weight-bearing

Buoyancy decreases the load placed on the lower limbs, allowing patients to practise walking with less pain and greater confidence.

This can be particularly valuable for individuals with impaired balance or reduced muscle strength.

Natural resistance

Walking through water provides continuous multidirectional resistance, promoting muscle activation throughout the gait cycle without requiring external weights.

Clinical implications

Although this was a small pilot study, the results suggest that aquatic treadmill training may be a valuable addition to stroke rehabilitation.

Potential benefits include:

• improved walking speed
• greater walking endurance
• improved gait symmetry
• excellent treatment adherence
• possible improvements in cerebrovascular health

The authors emphasise that larger randomised controlled trials are needed before definitive conclusions can be drawn, but the preliminary findings are encouraging.

Conclusion

This feasibility study demonstrates that aquatic treadmill training after stroke is safe, well tolerated and highly acceptable for community-dwelling stroke survivors.

After only four weeks of training, several participants achieved clinically meaningful improvements in walking performance, while preliminary evidence suggested favourable changes in cerebrovascular function. Although larger studies are required, aquatic treadmill training appears to be a promising addition to modern stroke rehabilitation programmes.