Aquatic interventions

Evidence Reviewed as of before: 26-02-2021
Author(s)*: Annabel McDermott, OT; Tatiana Ogourtsova, PhD OT
Patient/Family Information Table of contents

Introduction

Aquatic interventions are considered applicable to post-stroke rehabilitation as the properties of water support the effects of exercise on recovery.

An early Cochrane review (Merholz, Kugler & Pohl, 2011) that looked at the effect of water-based exercise on activities of daily living (ADLs) and other clinical outcomes (walking speed, postural control, muscle strength, aerobic fitness) after stroke included 4 studies (all studies are included in this review) and concluded that there was not enough evidence at that time to determine whether water-based exercise reduced disability after stroke.

Since that time there have been several systematic reviews and meta-analyses of aquatic interventions specific to the stroke population. Recent reviews have concluded that aquatic interventions are useful for improving balance (Iatridou et al., 2018; Xie et al., 2019; Nascimento et al., 2020) and walking skills (Xie et a., 2019; Nascimento et al., 2020). A positive effect has not been found in relation to ADLs (Xie et al., 2019).

Most recently, Veldema & Jansen’s (2020) analysis of 28 studies (all studies are included in this review) concluded that aquatic therapies are more effective than no treatment for improving walking, balance, emotional status/health-related quality of life, spasticity and physiological indicators; and are more effective than land-based therapies for improving walking, balance, muscular strength, proprioception, health-related quality of life, physiological indicators and cardiorespiratory fitness.

This Stroke Engine review includes 31 studies comprised of 11 high quality RCTs, 17 fair quality RCTs and 3 quasi-experimental studies. Most studies (N=26) were conducted with participants in the chronic phase of stroke recovery; all other studies were conducted with individuals in the subacute phase of recovery. For the purpose of this review, aquatic therapy interventions are defined as any stroke rehabilitation program conducted in controlled water environments. Aquatic programs encompass lower-extremity exercises, trunk exercises, balance activities, obstacle courses, dual-task training, hydrokinesitherapy, hydrotherapy, proprioceptive exercises, treadmill training, task-oriented training, and programs that draw on defined methods (e.g. Bad Ragaz Ring method and programs using Proprioceptive Neuromuscular Facilitation, Halliwick method, Ai Chi method). Control groups include no treatment and on-land programs (e.g. conventional rehabilitation, physical therapy, upper extremity function exercises, proprioceptive exercise, aerobic exercise, obstacle training, PNF lower extremity exercises, treadmill training/backward treadmill training, task-oriented training, trunk exercises, motor dual task training).

Overall, the results from this review found strong evidence (level 1a – from two or more high quality RCTs) to indicate that that aquatic interventions improve* lower extremity muscle strength and gait during the subacute phase of recovery; and balance, mobility and walking speed in the chronic phase of stroke recovery. Further, there was moderate evidence (level 1b – from at least one high quality RCT) that aquatic interventions improve* cardiovascular fitness parameters, gait parameters, muscle activity, pain and walking endurance in the chronic phase of stroke recovery.

* More than land-based interventions or no treatment.

Patient/Family Information

What are aquatic interventions?

 Aquatic interventions are exercise programs performed in a controlled water environment (e.g. in a pool).

Aquatic therapy is also referred to as:

  • water-based therapy
  • pool therapy
  • hydrotherapy
  • hydrokinesiotherapy

Why are aquatic interventions used for?

 It is common to experience physical difficulties after a stroke, such as difficulty with walking and balance. Exercise after a stroke is very important to recovery. It is necessary to continue to exercise after a stroke, to avoid further muscle weakness and reduced fitness. Exercise can also have a positive effect on mental health and neurological health.

Aquatic interventions can be suitable for different levels of ability and recovery after stroke. Aquatic therapy is used in stroke rehabilitation because water provides a safe and comfortable environment for exercise. There are several ways in which aquatic therapy assists recovery:

  • The density and viscosity (thickness) of water provides buoyancy to support body weight. This reduces the impact of movement on joints, allows for increased mobility, and reduces the risk of falls when exercising.
  • The hydrostatic pressure of water provides resistance for muscle strengthening. This pressure also provides increased sensory input to the muscles and joints.
  • Water can provide relief for muscles and joints.

Are there different types of aquatic interventions?

 Yes, there are different types of aquatic therapy used in stroke rehabilitation. Rehabilitation clinicians may choose a specific program because of:

  • the method (e.g. task-oriented training, Halliwick method, Ai Chi method)
  • the equipment (e.g. obstacle courses, treadmills)
  • the goal (e.g. improving upper body strength, lower body strength, balance or proprioception)

How do I do aquatic therapy?

 Your stroke rehabilitation team will talk with you to determine whether aquatic therapy is available, safe, and suitable for your recovery. Your rehabilitation clinician will develop a program that addresses your specific recovery needs and goals. Your clinician will supervise your session and will instruct you on the exercises and movements. They may assist you in the pool or direct you from beside the pool, depending on safety.

Do aquatic interventions work?

Researchers have done studies to see if aquatic therapy helps people who have had a stroke. There is good evidence that aquatic therapy can improve balance and walking skills.

There is strong evidence that aquatic therapy is helpful in the subacute phase of stroke recovery (1-6 months after the stroke) for improving:

  • lower extremity muscle strength
  • gait

There is moderate to strong evidence that aquatic therapy is helpful in the chronic phase of stroke recovery (more than 6 months after the stroke) for improving:

  • balance
  • mobility
  • walking speed
  • gait
  • walking endurance
  • cardiovascular fitness
  • muscle activity
  • pain

Other studies show that aquatic therapy is also helpful for improving emotional status and quality of life (related to health).

Note: These studies showed that aquatic interventions were more effective than land-based interventions or no treatment.

Are there any side effects or risks?

There are safety risks to consider when starting aquatic therapy after stroke. Risks include:

  • Slips and falls on wet surfaces around pools. The clinician will assess the individual’s safety and mobility before starting the program. The clinician will supervise or assist the individual to enter and exit the pool safely.
  • Drowning and heat exhaustion. The clinician will closely supervise the individual when doing exercises. The clinician will monitor the pool temperature and the individual’s wellness during the session.
  • Skin irritation and infection. Aquatic therapy should be done in a pool with controlled pH levels and an environment with frequent cleaning routines. The clinician should follow hygiene and infection control procedures.

Aquatic therapy should be done under supervision of a rehabilitation clinician. The clinician will choose a program that is safe and that suits the person’s recovery.

Who provides the treatment?

Aquatic interventions are performed under the supervision of a trained clinician. The clinician will choose specific exercises that use the physical properties of water to benefit the patient. The program and exercises will be selected according to each person’s recovery stage, abilities, needs and rehabilitation goals.

Who can help me?

 It is important to obtain medical clearance from your physician before starting an exercise program after stroke. Talk with your rehabilitation team if you are interested in aquatic therapy for stroke recovery.

Clinician Information

Note: When reviewing the findings, it is important to note that they are always made according to randomized clinical trial (RCT) criteria – specifically as compared to a control group. To clarify, if a treatment is “effective” it implies that it is more effective than the control treatment to which it was compared. Non-randomized studies are no longer included when there is sufficient research to indicate strong evidence (level 1a) for an outcome.

 

Results Table

View results table

Outcomes

Subacute phase

Activities of Daily Living
Conflicting
4

Three high quality RCTs (Zhang et al., 2016; Han & Im, 2018; Lee et al., 2018) investigated the effect of aquatic interventions on Activities of Daily Living (ADLs) in the subacute phase of stroke recovery.

The first high quality RCT (Zhang et al., 2016) randomized participants to receive aquatic therapy or land-based physiotherapy. ADLs were measured using the Barthel Index at post-treatment (8 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. land-based physiotherapy.

The second high quality RCT (Han & Im, 2018) randomized participants to receive aquatic treadmill training or land-based aerobic exercise. ADLs were measured using the Korean modified Barthel Index at post-treatment (6 weeks). No significant between-group difference was found.

The third high quality RCT (Lee et al., 2018) randomized participants to receive aquatic treadmill training or on-land aerobic exercise. ADLs were measured using the Korean modified Barthel Index at post-treatment (4 weeks). No significant between-group difference was found.

Conclusion: There is conflicting evidence (level 4) regarding the effectiveness of aquatic interventions on Activities of Daily Living in the subacute phase of stroke recovery. While one high quality RCT found that aquatic interventions were more effective than on-land programs, two other high quality RCTs found that an aquatic therapy program was no more effective than a land-based aerobic program.

Arterial stiffness
Not effective
1b

One high quality RCT (Lee et al., 2018) investigated the effect of aquatic interventions on arterial stiffness in the subacute phase of stroke recovery. The high quality RCT randomized participants to receive aquatic treadmill training or on-land aerobic exercise. Arterial stiffness (paretic/non-paretic) was measured using an oscillometric method at post-treatment (4 weeks). No significant between-group difference was found.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT that aquatic interventions are not more effective than on-land interventions for reducing arterial stiffness in the subacute phase of stroke recovery.

Balance
Conflicting
4

Two high quality RCTs (Tripp & Krakow, 2014; Lee et al., 2018) and one fair quality RCT (Chan et al., 2017) investigated the effect of aquatic interventions on balance in the subacute phase of stroke recovery.

The first high quality RCT (Tripp & Krakow, 2014) randomized participants to receive aquatic therapy using the Halliwick method, or time-matched conventional physiotherapy; both groups received additional physiotherapy. Balance was measured using the Berg Balance Scale (BBS) and the Functional Reach Test at post-treatment (2 weeks). A significant between-group difference was found on one measure (BBS), in favour of aquatic therapy vs. conventional physiotherapy.

The second high quality RCT (Lee et al., 2018) randomized participants to receive aquatic treadmill training or on-land aerobic exercise. Balance was measured using the BBS at post-treatment (4 weeks). No significant between-group difference was found.

The fair quality RCT (Chan et al., 2017) randomized participants to receive aquatic therapy or conventional rehabilitation; both groups received additional conventional rehabilitation. Balance was measured using the BBS at post-treatment (6 weeks). No significant between-group difference was found.

Conclusion: There is conflicting evidence (level 4) regarding the effectiveness of aquatic interventions on balance in the subacute phase of stroke recovery. While one high quality RCT found that a 2-week aquatic therapy program was more effective than physiotherapy, a second high quality RCT and a fair quality RCT found that aquatic interventions (4-week aquatic treadmill training, 6-week aquatic therapy) were not more effective than on-land rehabilitation programs.

Cardiorespiratory fitness parameters
Conflicting
4

Two high quality RCTs (Han & Im, 2018; Lee et al., 2018) investigated the effect of aquatic interventions on cardiorespiratory fitness parameters in the subacute phase of stroke recovery.

The first high quality RCT (Han & Im, 2018) randomized participants to receive aquatic treadmill training or land-based aerobic exercise. Cardiorespiratory fitness parameters (Peak oxygen uptake, Peak rate pressure product, Resting heart rate, Peak heart rate, Age-predicted maximum heart rate, Exercise tolerance test duration, Respiratory exchange ratio) were measured at post-treatment (6 weeks). Significant between-group differences were found on four of seven measures (Oxygen uptake, Peak heart rate, Age-predicted maximum heart rate, Exercise tolerance test duration), in favour of aquatic therapy vs. land-based aerobic exercise.

The second high quality RCT (Lee et al., 2018) randomized participants to receive aquatic treadmill training or on-land aerobic exercise. Cardiorespiratory fitness parameters (Resting heart rate, Resting systolic/diastolic blood pressure, Maximal heart rate, Maximal systolic/diastolic blood pressure, Maximal rate pressure product, Respiratory exchange ratio, Maximal oxygen consumption) were measured at post-treatment (4 weeks). No significant between-group differences were found.

Conclusion: There is conflicting evidence (level 4) regarding the effectiveness of aquatic interventions on cardiorespiratory fitness parameters in the subacute phase of stroke recovery. While both interventions compared aquatic treadmill training with on-land aerobic exercise, the 6-week program found between-group differences on some measures of cardiorespiratory fitness whereas the 4-week program found no differences between groups.

Gait
Effective
1a

Two high quality RCTs (Tripp & Krakow, 2014; Zhang et al., 2016) investigated the effect of aquatic interventions on gait in the subacute phase of stroke recovery.

The first high quality RCT (Tripp & Krakow, 2014) randomized participants to receive aquatic therapy using the Halliwick method, or time-matched conventional physiotherapy; both groups received additional physiotherapy. Gait was measured using the Functional Ambulation Categories at post-treatment (2 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. conventional physiotherapy.

The second high quality RCT (Zhang et al., 2016) randomized participants to receive aquatic therapy or land-based physiotherapy. Gait was measured using the Functional Ambulation Categories at post-treatment (8 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. land-based physiotherapy.

Conclusion: There is strong evidence (level 1a) from two high quality RCTs that aquatic interventions are more effective than on-land interventions for improving gait in the subacute phase of stroke recovery.

Mobility
Not effective
1b

One high quality RCT (Tripp & Krakow, 2014) and one fair quality RCT (Chan et al., 2017) investigated the effect of aquatic interventions on mobility in the subacute phase of stroke recovery.

The high quality RCT (Tripp & Krakow, 2014) randomized participants to receive aquatic therapy using the Halliwick method, or time-matched conventional physiotherapy; both groups received additional physiotherapy. Mobility was measured using the Rivermead Mobility Index at post-treatment (2 weeks). No significant between-group difference was found.

The fair quality RCT (Chan et al., 2017) randomized participants to receive aquatic therapy or conventional rehabilitation; both groups received additional conventional rehabilitation. Mobility was measured using the Timed Up and Go test and ambulatory skills were measured using the Community Balance and Mobility Test at post-treatment (6 weeks). No significant between-group differences were found.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT and one fair quality RCT that aquatic interventions are not more effective than on-land interventions for improving mobility in the subacute phase of stroke recovery.

Motor function - lower extremity
Not effective
1b

One high quality RCT (Lee et al., 2018) investigated the effect of aquatic interventions on motor function in the subacute phase of stroke recovery. The high quality RCT randomized participants to receive aquatic treadmill training or on-land aerobic exercise. Lower extremity motor function was measured using the Fugl-Meyer Assessment (FMA, FMA – Lower Limb score) at post-treatment (4 weeks). No significant between-group difference was found.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT that aquatic interventions are not more effective than on-land interventions for improving lower extremity motor function in the subacute phase of stroke recovery.

Muscle strength - lower extremity
Effective
1a

Two high quality RCTs (Zhang et al., 2016; Lee et al., 2018) investigated the effect of aquatic interventions on lower extremity muscle strength in the subacute phase of stroke recovery.

The first high quality RCT (Zhang et al., 2016) randomized participants to receive aquatic therapy or land-based physiotherapy. Muscle activity (Knee extension/flexion torque/cocontraction ratio, Ankle dorsiflexion/plantarflextion torque/cocontraction ratio) was measured at post-treatment (8 weeks). Significant between-group differences were found in some measures (Knee extension torque, Knee extension cocontraction ratio, Ankle plantarflextion torque), in favour of aquatic therapy vs. land-based physiotherapy.

The second high quality RCT (Lee et al., 2018) randomized participants with subacute stroke to receive aquatic treadmill training or on-land aerobic exercise. Muscle strength was measured by dynamometer (isometric knee flexion/extension – paretic/non-paretic limb) at post-treatment (4 weeks). A significant between-group difference in muscle strength of the paretic limb (knee flexion, knee extension) was found, in favour of aquatic therapy vs. on-land aerobic exercise.

Conclusion: There is strong evidence (level 1a) from two high quality RCTs that aquatic interventions are more effective than on-land interventions for improving lower extremity muscle strength in the subacute phase of stroke recovery.

Quality of life
Not effective
1b

One high quality RCT (Lee et al., 2018) investigated the effect of aquatic interventions on quality of life in the subacute phase of stroke recovery. The high quality RCT randomized participants to receive aquatic treadmill training or on-land aerobic exercise. Health-related quality of life was measured using the EQ-5D-3L at post-treatment (4 weeks). No significant between-group difference was found.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT that aquatic interventions are not more effective than on-land interventions for improving quality of life in the subacute phase of stroke recovery.

Spasticity
Not effective
1b

One high quality RCT (Zhang et al., 2016) investigated the effect of aquatic interventions on spasticity in the subacute phase of stroke recovery. The high quality RCT randomized participants to receive aquatic therapy or land-based physiotherapy. Spasticity was measured using the Modified Ashworth Scale (Knee flexion, Ankle dorsiflexion) at post-treatment (8 weeks). No significant between-group difference was found.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT that aquatic interventions are not more effective than on-land interventions for reducing spasticity in the subacute phase of stroke recovery.

Walking endurance
Not effective
1b

One high quality RCT (Han & Im, 2018) and one fair quality RCT (Chan et al., 2017) investigated the effect of aquatic interventions on walking endurance in the subacute phase of stroke recovery.

The high quality RCT (Han & Im, 2018) randomized participants to receive aquatic treadmill training or land-based aerobic exercise. Walking endurance was measured using the Six Minute Walk Test at post-treatment (6 weeks). No significant between-group difference was found.

The fair quality RCT (Chan et al., 2017) randomized participants to receive aquatic therapy or conventional rehabilitation; both groups received additional conventional rehabilitation. Walking endurance was measured using the Two-Minute Walking Test at post-treatment (6 weeks). No significant between-group difference was found.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT and one fair quality RCT that aquatic interventions are not more effective than on-land interventions for improving walking endurance in the subacute phase of stroke recovery.

Chronic phase

Balance
Effective
1a

Six high quality RCTs (Chu et al., 2004; Zhu et al., 2016; Cha, Shin & Kim, 2017; Saleh, Rehab & Aly, 2019; Perez-de la Cruz, 2020; Perez-de la Cruz, 2021), ten fair quality RCTs (Noh et al., 2008; Lee, Ko & Cho, 2010; Park & Roh, 2011b; Park et al., 2014; Jung et al., 2014; Kim, Lee & Kim, 2015; Kim, Lee & Jung, 2015; Kim, Lee & Kim, 2016; Eyvaz, Dundar & Yesil, 2018; Aidar et al., 2018) and three quasi-experimental studies (Han, Kim & An, 2013; Montagna et al., 2014; Morer et al., 2020) investigated the effect of aquatic therapy interventions on balance in the chronic phase of stroke recovery.

The first high quality RCT (Chu et al., 2004) randomized participants to receive an aquatic lower extremity program or a land-based upper extremity training program. Balance was measured using the Berg Balance Scale (BBS) at post-treatment (8 weeks). No significant between-group difference was found.

The second high quality RCT (Zhu et al., 2016) randomized participants to receive hydrotherapy or land-based exercises. Balance was measured using the BBS and the Functional Reach Test (FRT) at post-treatment (4 weeks). A significant between-group difference was found on one measure (FRT), in favour of hydrotherapy vs. land-based exercise.

The third high quality RCT (Cha, Shin & Kim, 2017) randomized participants to receive aquatic therapy using the Bad Ragaz Ring method or time-matched conventional physical therapy; both groups received additional physical therapy. Balance was measured using the Biodex Balance Master (a balance measurement system) at post-treatment (6 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. physical therapy.

The fourth high quality RCT (Saleh, Rehab & Aly, 2019) randomized participants to receive aquatic motor dual task training or land-based motor dual task training. Dynamic balance was measured using the Biodex Balance System (Overall Stability Index, Anteroposterior Stability Index, Mediolateral Stability Index) at post-treatment (6 weeks). A significant between-group difference was found on all measures of dynamic balance, in favour of aquatic therapy vs. land-based training.

The fifth high quality RCT (Perez-de la Cruz, 2020) randomized participants to receive Ai-Chi aquatic therapy, on-land exercises, or combined aquatic therapy + on-land exercises. Balance was measured using the Tinetti test (Total score), the 360 degree turn test, and single-leg stance balance tests (Right/Left leg) at post-treatment (12 weeks) and one-month follow-up. Significant between-group differences were found on two measures (Tinetti test, 360-degree turn test) at both timepoints, in favour of aquatic therapy vs. on-land therapy.
Note: Significant between-group differences were also found (Tinetti test, 360-degree turn test) at both timepoints, in favour of combined therapy vs. on-land exercises. There was a significant between-group difference (360 degree turn test) at both timepoints, in favour of combined therapy vs. aquatic therapy.

The sixth high quality RCT (Perez-de la Cruz, 2021) randomized participants to receive aquatic therapy, on-land exercises, or combined aquatic therapy + on-land exercises. Balance was measured using the BBS and tandem stance (eyes open) at post-treatment (12 weeks) and one-month follow-up. There were significant between-group differences on both measures at both timepoints, in favour of aquatic therapy vs. on-land exercises.
Note: There was a significant between-group difference in one measure (BBS) at both timepoints, in favour of aquatic therapy vs. combined therapy; in one measure (tandem stance) at follow-up only, in favour of combined therapy vs. aquatic therapy; and in one measure (tandem stance) at both timepoints, in favour of combined therapy vs. on-land exercises.

The first fair quality RCT (Noh et al., 2008) randomized participants to receive aquatic therapy or conventional rehabilitation. Balance was measured using the BBS at post-treatment (8 weeks). A significant difference in change scores from baseline to post-treatment was found, in favour of aquatic therapy vs. conventional rehabilitation.

The second fair quality RCT (Lee, Ko & Cho, 2010) randomized participants to receive aquatic task-oriented training or on-ground task-oriented training. Balance was measured using the Good Balance System to measure static balance (Anteroposterior/mediolateral sway velocity – eyes open, eyes closed) and dynamic balance (Time, Distance) at post-treatment (12 weeks). A significant between-group difference was found in dynamic balance only (time, distance), in favour of aquatic vs. on-ground task-oriented training.

The third fair quality RCT (Park & Roh, 2011b) randomized participants to receive aquatic exercises or land exercises. Static balance was measured using the Good Balance System (Mediolateral sway velocity – eyes open/eyes closed; Anteroposterior sway velocity – eyes open/eyes closed; Velocity movement – eyes open/eyes closed) at post-treatment (6 weeks). Significant between-group differences were seen in static balance measures (Mediolateral sway velocity – eyes open, Anteroposterior sway velocity – eyes open, Velocity movement – eyes open), in favour of aquatic exercises vs. land exercises.

The fourth fair quality RCT (Park et al., 2014) randomized participants to receive aquatic treadmill training or no additional training; both groups received conventional rehabilitation. Balance was measured using the Balance System SD (Static balance – anteroposterior sway, mediolateral sway, total; Dynamic balance) at post-treatment (4 weeks). No significant between-group differences were found.

The fifth fair quality RCT (Jung et al., 2014) randomized participants to receive aquatic obstacle training or land-based obstacle training. Static balance was measured using the Good Balance system (Mediolateral sway velocity – eyes closed, Anteroposterior sway velocity – eyes closed, Sway area) at post-treatment (12 weeks). Significant between-group differences were found on all measures, in favour of aquatic therapy vs. land-based obstacle training.

The sixth fair quality RCT (Kim, Lee & Kim, 2015) randomized participants to receive aquatic proprioceptive neuromuscular facilitation (PNF) lower extremity exercises or on-ground PNF lower extremity exercises. Balance was measured using the BBS, FRT and One Leg Stand Test at post-treatment (6 weeks). Significant between-group differences were found on all measures of balance, in favour of aquatic PNF exercises vs. on-ground PNF exercises.

The seventh fair quality RCT (Kim, Lee & Jung, 2015) randomized patients to receive aquatic coordination movement using Proprioceptive Neuromuscular Facilitation (PNF) and Neurodevelopmental Therapy (NDT) or NDT alone. Balance was measured using the BBS and the FRT at post-treatment (6 weeks). Significant between-group differences were found on both measures of balance, in favour of aquatic PNF vs. no aquatic therapy.

The eighth fair quality RCT (Kim, Lee & Kim, 2016) randomized participants to receive aquatic dual-task training or no aquatic therapy; both groups received neurodevelopmental therapy. Balance was measured using the BBS and FRT at post-treatment (6 weeks). A Significant between-group difference was found on both measures, in favour of aquatic therapy vs. no aquatic therapy.

The ninth fair quality RCT (Eyvaz, Dundar & Yesil, 2018) randomized participants to receive water-based exercises or land-based exercises; both groups received additional land-based exercises. Balance was measured using the BBS and the Sportak Balance Device (Static balance index, Dynamic balance index) at post-treatment (6 weeks). A significant difference was found on one measure (BBS), in favour of land-based exercise vs. water-based exercise.

The tenth fair quality RCT (Aidar et al., 2018) randomized participants to receive an aquatic exercise program or no treatment. Balance was measured using the BBS at post-treatment (12 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. no treatment.

The first non-randomized study (Han, Kim & An, 2013) allocated participants to receive an aquatic proprioceptive exercise program or a land-based proprioceptive exercise program. Balance was measured using the BBS and sway area was measured using the Good Balance system (eyes open, eyes closed) at post-treatment (6 weeks). Significant between-group differences were found on all measures, in favour of aquatic therapy vs. land-based therapy.

The second non-randomized study (Montagna et al., 2014) assigned participants to receive aquatic physiotherapy using the Halliwick method. Balance was measured using the BBS at post-treatment (18 sessions). A significant improvement was found.

The third non-randomized study (Morer et al., 2020) assigned participants to receive aquatic therapy + thalassotherapy. Balance was measured using the BBS at post-treatment (2 weeks). A significant improvement was found.

Conclusion: There is strong evidence (level 1a) from five high quality RCTs, nine fair quality RCTs and one quasi-experimental study that aquatic therapy interventions are more effective than land-based interventions or no treatment for improving balance in the chronic phase of stroke recovery.
Note: However, one high quality RCT found that an aquatic lower extremity intervention program was no more effective than a comparative land-based upper extremity program; one fair quality RCT found that aquatic treadmill training was no more effective than no treatment; and another fair quality RCT found that water-based exercises were less effective than land-based exercises for improving balance. In contrast, two other quasi-experimental studies noted a significant improvement in balance following aquatic interventions.

Cardiovascular fitness parameters
Effective
1b

One high quality RCT (Chu et al., 2004) investigated the effect of an aquatic intervention on cardiovascular fitness in the chronic phase of stroke recovery. The high quality RCT randomized participants to receive an aquatic lower extremity program or a land-based upper extremity training program. Maximal oxygen uptake (VO2max) and maximal workload (watts) were measured using a cycle ergometer test at post-treatment (8 weeks). A significant between-group difference was found on both measures, in favour of aquatic therapy lower extremity training vs. land-based upper extremity training.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT that aquatic therapy intervention is more effective than a land-based intervention (upper extremity training) for improving cardiovascular fitness parameters in the chronic phase of stroke recovery.

Functional independence
Conflicting
4

Two fair quality RCTs (Kim, Lee & Kim, 2015; Eyvaz, Dundar & Yesil, 2018) have investigated the effect of aquatic therapy interventions on functional independence in the chronic phase of stroke recovery.

The first fair quality RCT (Kim, Lee & Kim, 2015) randomized participants to receive aquatic proprioceptive neuromuscular facilitation (PNF) lower extremity exercises or on-ground PNF lower extremity exercises. Functional independence was measured using the Functional Independence Measure (FIM) at post-treatment (6 weeks). A significant between-group difference was found, in favour of aquatic PNF exercises vs. on-ground PNF exercises.

The second fair quality RCT (Eyvaz, Dundar & Yesil, 2018) randomized participants to receive water-based exercises or land-based exercises; both groups received additional land-based exercises. Functional independence was measured using the FIM at post-treatment (6 weeks). No significant between-group difference was found.

Conclusion: There is conflicting evidence (level 4) regarding the effectiveness of aquatic therapy on functional independent in chronic phase of stroke recovery. While one fair quality RCT found that aquatic therapy was more effective than land-based exercises, another fair quality RCT found that it was not more effective.
Note: Differences in outcomes may relate to the different forms of aquatic intervention and/or intervention intensity: aquatic exercises performed for 60 mins/session for 3 days/week were not more effective than land-based exercises; aquatic PNF performed for 30 mins/session, 5 sessions/week were more effective than land-based PNF exercises.

Gait ability
Not effective
2a

One fair quality RCT (Noh et al., 2008) has investigated the effect of aquatic interventions on gait ability in the chronic phase of stroke recovery. The fair quality RCT randomized participants to receive aquatic therapy or conventional rehabilitation. Gait ability was measured using the Modified Motor Assessment Scale at post-treatment (8 weeks). No significant difference was found.

Conclusion: There is limited evidence (level 2a) from one fair quality RCT that aquatic interventions are not more effective than land-based interventions for improving gait ability in the chronic phase of stroke recovery.

Gait parameters
Effective
1b

One high quality RCT (Saleh, Rehab & Aly, 2019) and three fair quality RCTs (Park et al., 2012; Furnari et al., 2014; Park et al., 2016) have investigated the effect of aquatic interventions on gait parameters in the chronic phase of stroke recovery.

The high quality RCT (Saleh, Rehab & Aly, 2019) randomized participants to receive aquatic motor dual task training or land-based motor dual task training. Gait parameters (Walking speed, Step length – paretic/non-paretic limb, Time of support on the paretic limb) were measured using the Biodex Gait Trainer at post-treatment (6 weeks). A significant between-group difference was found on all gait parameters, in favour of aquatic training vs. land-based training.

The first fair quality RCT (Park et al., 2012) randomized participants to receive aquatic treadmill training or land-based treadmill training. Gait parameters (Joint angles on heel contact and toe off the ground [hip flexion, knee extension, plantarflexion/dorsiflexion]) were measured at post-treatment (6 weeks). Significant between-group differences were found (hip flexion – heel contact, toe off; knee extension – heel contact, toe-off), in favour of aquatic treadmill training vs. land-based treadmill training.

The second fair quality RCT (Furnari et al., 2014) randomized participants to receive hydrokinesytherapy or conventional physical therapy; both groups received additional physical therapy. Gait parameters (gait speed, cadence, stance phase, swing phase, double support phase, semistep length) were measured using a Modular Clinical Electronic Baropodometer at post-treatment (8 weeks). Significant between-group differences were found on most measures (gait speed, cadence, stance phase, swing phase, double support phase), in favour of aquatic therapy vs. physical therapy.

The third fair quality RCT (Park et al., 2016) randomized participants to receive aquatic trunk exercises or land-based trunk exercises. Gait parameters were measured using the Gait trainer 2 analysis system (Walking speed, Walking cycle, Stance phase, Stride length, Symmetry index – stance phase/stride length) at post-treatment (4 weeks). Significant between-group differences were found on two gait parameters (Walking cycle, Stride length – paretic limb), in favour of land-based trunk exercises vs. aquatic trunk exercises.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT and two fair quality RCTs that aquatic interventions are more effective than land-based interventions for improving gait parameters in the chronic phase of stroke recovery.
Note: However, one fair quality RCT found that land-based exercises were more effective than water-based trunk exercises for improving some gait parameters.

Mobility
Conflicting
4

Three high quality RCTs (Zhu et al., 2016; Cha, Shin & Kim, 2017; Perez-de la Cruz, 2021), six fair quality RCTs (Park et al., 2011a; Kim, Lee & Jung, 2015; Kim, Lee & Kim, 2015; Kim, Lee & Kim, 2016; Eyvaz, Dundar & Yesil, 2018; Aidar et al., 2018) and two quasi-experimental studies (Montagna et al., 2014; Morer et al., 2020) investigated the effect of aquatic interventions on mobility in the chronic phase of stroke recovery.

The first high quality RCT (Zhu et al., 2016) randomized participants to receive hydrotherapy or land-based exercises. Mobility was measured using the Timed Up and Go Test (TUG) at post-treatment (4 weeks). No significant between-group difference was found.

The second high quality RCT (Cha, Shin & Kim, 2017) randomized patients to receive aquatic therapy using the Bad Ragaz Ring method or time-matched conventional physical therapy; both groups received additional physical therapy. Mobility was measured using the TUG at post-treatment (6 weeks). No significant between-group difference was found.

The third high quality RCT (Perez-de la Cruz, 2021) randomized participants to receive aquatic therapy, on-land exercises, or combined aquatic therapy + on-land exercises. Mobility was measured using the TUG and Five Times Sit-to-Stand test (FTSTS) at post-treatment (12 weeks) and one-month follow-up. There were significant between-group differences in both measures at both timepoints, in favour of aquatic therapy vs. on-land exercises.
Note: There was a significant between-group difference in one measure (FTSTS) at both timepoints, in favour of combined therapy vs. aquatic therapy; there were significant between-group differences in both measures at both timepoints, in favour of combined therapy vs. on-land exercises.

The first fair quality RCT (Park et al., 2011a) randomized participants to receive aquatic exercises or land exercises. Mobility was measured using the Performance-Oriented Mobility Assessment at post-treatment (6 weeks). A significant between-group difference was found, in favour of aquatic exercise vs. land exercise.

The second fair quality RCT (Kim, Lee & Jung, 2015) randomized patients to receive aquatic coordination movement using Proprioceptive Neuromuscular Facilitation (PNF) and Neurodevelopmental Therapy (NDT) or NDT alone. Mobility was measured using the TUG at post-treatment (6 weeks). A significant between-group difference was found, in favour of aquatic PNF vs. no aquatic therapy.

The third fair quality RCT (Kim, Lee & Kim, 2015) randomized participants to receive aquatic proprioceptive neuromuscular facilitation (PNF) lower extremity exercises or on-ground PNF lower extremity exercises. Mobility was measured using the TUG at post-treatment (6 weeks). A significant between-group difference was found, in favour of aquatic PNF exercises vs. on-ground PNF exercises.

The fourth fair quality RCT (Kim, Lee & Kim, 2016) randomized participants to receive aquatic dual-task training or no aquatic therapy; both groups received neurodevelopmental therapy. Mobility was measured using the TUG and the Five Times Sit-to-Stand Test at post-treatment (6 weeks). A significant between-group difference was found on both measures, in favour of aquatic therapy vs. no therapy.

The fifth fair quality RCT (Eyvaz, Dundar & Yesil, 2018) randomized participants to receive water-based exercises or land-based exercises; both groups received additional land-based exercises. Mobility was measured using the TUG test at post-treatment (6 weeks). No significant between-group difference was found.

The sixth fair quality RCT (Aidar et al., 2018) randomized participants to receive an aquatic exercise program or no treatment. Mobility was measured using the TUG and a test of getting up from a sitting position at post-treatment (12 weeks). A significant between-group difference was found on both measures of mobility, in favour of aquatic therapy vs. no treatment.

The first non-randomized study (Montagna et al., 2014) assigned participants to receive aquatic physiotherapy using the Halliwick method. Mobility was measured using the TUG at post-treatment (18 sessions). A significant improvement was found.

The second non-randomized study (Morer et al., 2020) assigned participants to receive aquatic therapy + thalassotherapy. Mobility was measured using the TUG at post-treatment (2 weeks). A significant improvement was found.

Conclusion: There is conflicting evidence (level 4) regarding the effect of aquatic therapy on mobility in the chronic phase of stroke recovery. While one high quality RCT and five fair quality RCTs found that aquatic interventions were more effective than land-based interventions or no treatment, two high quality RCTs and one fair quality RCT found that aquatic interventions were not more effective than comparison interventions (land-based exercises, conventional physical therapy).

Mood
Effective
2a

Two fair quality RCTs (Aidar et al., 2013; Aidar et al., 2018) investigated the effect of aquatic interventions on mood in the chronic phase of stroke recovery.

The first fair quality RCT (Aidar et al., 2013) randomized participants to receive an aquatic exercise program or no treatment. Anxiety was measured using the State Trait Anxiety Inventory (IDATE – I Anxiety Trait; II Anxiety State) and depression was measured using the Beck Depression Inventory at post-treatment (12 weeks). A significant between-group difference was found on all measures of mood, in favour of aquatic therapy vs. no treatment.

The second fair quality RCT (Aidar et al., 2018) randomized participants to receive an aquatic exercise program or no treatment. Anxiety was measured using the State Trait Anxiety Inventory (IDATE – I Anxiety state, II Anxiety trait) and depression was measured using the BDI at post-treatment (12 weeks). A significant between-group difference was found on all measures of mood, in favour of aquatic therapy vs. no treatment.

Conclusion: There is limited evidence (level 2a) from two fair quality RCTs that aquatic interventions are more effective than no treatment in improving mood in the chronic phase of stroke recovery.

Muscle activity
Effective
1b

One high quality RCT (Cha, Shin & Kim, 2017) investigated the effect of aquatic interventions on muscle activity in the chronic phase of stroke recovery. The high quality RCT randomized patients to receive aquatic therapy using the Bad Ragaz Ring method or time-matched conventional physical therapy; both groups received additional physical therapy. Muscle activity was measured using electromyography (EMG – Tibialis anterior, Gastrocnemius) at post-treatment (6 weeks). A significant between-group difference was found in favour of aquatic therapy vs. physical therapy.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT that aquatic interventions are more effective than land-based interventions for improving muscle activity in the chronic phase of stroke recovery.

Pain
Effective
1b

One high quality RCT (Perez-de la Cruz, 2020) and one quasi-experimental study (Morer et al., 2020) investigated the effect of aquatic interventions on pain in the chronic phase of stroke recovery.

The high quality RCT (Perez-de la Cruz, 2020) randomized participants to receive Ai-Chi aquatic therapy, on-land exercises, or combined aquatic therapy + on-land exercises. Pain was measured using a visual analogue scale at post-treatment (12 weeks) and one-month follow-up. A significant between-group difference was found at both timepoints, in favour of aquatic therapy vs. on-land exercises.
Note: A significant between-group difference in pain was found at both timepoints, in favour of combined therapy vs. on-land exercises.

The non-randomized study (Morer et al., 2020) assigned participants to receive aquatic therapy + thalassotherapy. Pain was measured using a visual analogue scale at post-treatment (2 weeks). A significant improvement was found.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT that aquatic interventions are more effective than on-land interventions for reducing pain in the chronic phase of stroke recovery. A non-randomized study also reported reduced pain following aquatic intervention.

Postural stability - dynamic
Conflicting
4

Two fair quality RCTs (Kim, Lee & Kim, 2016; Kum & Shin, 2017) investigated the effect of aquatic interventions on dynamic postural stability in the chronic phase of stroke recovery.

The first fair quality RCT (Kim, Lee & Kim, 2016) randomized participants to receive aquatic dual-task training or no aquatic therapy; both groups received neurodevelopmental therapy. Postural stability when walking was measured using the Functional Gait Assessment at post-treatment (6 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. no aquatic therapy.

The second fair quality RCT (Kum & Shin, 2017) randomized participants to receive underwater backward treadmill training or on-ground backward treadmill training. Postural stability when walking was measured using the Functional Gait Assessment at post-treatment (6 weeks). No significant between-group difference was found.

Conclusion: There is conflicting evidence (level 4) between two fair quality RCTs regarding the effectiveness of aquatic interventions on dynamic postural stability in the chronic phase of stroke recovery. One study found that aquatic dual-task training was more effective than no training whereas a second study found that underwater backward treadmill training was no more effective than on-ground training.

Postural stability - static
Not effective
2a

One fair quality RCT (Furnari et al., 2014) and one quasi-experimental study (Montagna et al., 2014) investigated the effect of aquatic interventions on static postural stability in the chronic phase of stroke recovery.

The fair quality RCT (Furnari et al., 2014) randomized participants to receive hydrokinesytherapy or conventional physical therapy; both groups received additional physical therapy. Static postural stability was measured using baropodometry (plantar surface, plantar load – paretic/non-paretic) and stabilometry (length of the ball – eyes open/closed) at post-treatment (8 weeks). A significant between-group difference was found on one measure (length of ball – eyes open/closed), in favour of aquatic therapy vs. conventional physical therapy.

The non-randomized study (Montagna et al., 2014) assigned participants to receive aquatic physiotherapy using the Halliwick method. Plantar pressure distribution was measured using baropodometry (anterioposterior/mediolateral – eyes open, eyes closed, sit-to-stand) at post-treatment (18 sessions). No significant improvement was found.

Conclusion: There is limited evidence (level 2a) from one fair quality RCT that aquatic interventions are not more effective than on-ground interventions for improving static postural stability in the chronic phase of stroke recovery. A quasi-experimental study also reported no significant improvement in static postural stability following aquatic physiotherapy.

Proprioception
Effective
2a

Two fair quality RCTs (Park et al., 2011a; Kum & Shin, 2017) and one quasi-experimental study (Han, Kim & An, 2013) investigated the effect of aquatic interventions on proprioception in the chronic phase of stroke recovery.

The first fair quality RCT (Park et al., 2011a) randomized participants to receive aquatic exercises or land exercises. Proprioception of knee movements was measured using the Biometrics Motion Analysis System at post-treatment (6 weeks). A significant between-group difference was found, in favour of aquatic exercise vs. land exercise.

The second fair quality RCT (Kum & Shin, 2017) randomized participants to receive underwater backward treadmill training or on-ground backward treadmill training. Proprioception was measured using the joint angle recurrence method by smartphone protractor application while the participant was in one-legged stance (paretic hip flexion/extension, paretic knee flexion/extension), at post-treatment (6 weeks). Significant between-group differences were found on all measures, in favour of underwater backward treadmill training vs. on-ground backward treadmill training.

The non-randomized study (Han, Kim & An, 2013) allocated participants to receive an aquatic proprioceptive exercise program or a land-based proprioceptive exercise program. Proprioception was measured using the Biometrics motion analysis system at post-treatment (6 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. land-based therapy.

Conclusion: There is limited evidence (level 2a) from two fair quality RCTs and one quasi-experimental study that aquatic interventions are more effective than on-land interventions for improving proprioception in the chronic phase of stroke recovery.

Quality of life
Conflicting
4

One high quality RCT (Matsumoto et al., 2016), one fair quality RCT (Eyvaz, Dundar & Yesil, 2018) and two quasi-experimental studies (Montagna et al., 2014; Morer et al., 2020) investigated the effect of aquatic interventions on quality of life in the chronic phase of stroke recovery.

The high quality RCT (Matsumoto et al., 2016) randomized participants to receive aquatic therapy or no aquatic therapy; both groups received conventional rehabilitation. Quality of life was measured using the Short-Form 36 (SF-36: Physical functioning; Role physical; Bodily pain; General health; Vitality; Social functioning; Role-emotional; Mental health) at post-treatment (12 weeks). A significant between-group difference was found in change scores on all measures of quality of life in favour of aquatic therapy vs. no aquatic therapy.

The fair quality RCT (Eyvaz, Dundar & Yesil, 2018) randomized participants to receive water-based exercises or land-based exercises; both groups received additional land-based exercises. Quality of life was measured using the SF-36 (Vitality; Physical functioning; Role physical; Pain; General health; Social functioning; Role emotional; Mental health) at post-treatment (6 weeks). A significant between-group difference was found in one measure of quality of life (SF-36: Vitality), in favour of water-based exercises vs. land-based exercises. No other between-group differences were found.

The first non-randomized study (Montagna et al., 2014) assigned participants to receive aquatic physiotherapy using the Halliwick method. Quality of life was measured using the Stroke-Specific Quality of Life questionnaire (SS-QoL – Energy, Family roles, Language, Mobility, Mood, Personality, Self-care, Social roles, Thinking, Upper extremity function, Vision, Work/productivity, Total scores) at post-treatment (18 sessions). A significant improvement was found in one score only (Mobility).

The second non-randomized study (Morer et al., 2020) assigned participants to receive aquatic therapy + thalassotherapy. Health-related quality of life was measured using the EQ-5D (Mobility, Self-care, Usual activities, Pain/discomfort, Anxiety/depression scores) at post-treatment (2 weeks). A significant improvement was found on one measure (Mobility).

Conclusion: There is conflicting evidence (level 4) regarding the effectiveness of aquatic interventions on quality of life in the chronic phase of stroke recovery. One high quality RCT found that aquatic therapy was more effective than no aquatic therapy. One fair quality RCT found that water-based exercises were no more effective than comparable land-based exercises. Two quasi-experimental studies found an improvement in only one measure of quality of life (mobility) following aquatic interventions.

Self-perception of Health and Well-being
Effective
2b

One quasi-experimental study (Morer et al., 2020) investigated the effect of aquatic interventions on well-being in the chronic phase of stroke recovery. The non-randomized study assigned participants to receive aquatic therapy + thalassotherapy. Psychological well-being was measured using the WHO 5-item Well-Being Index and self-perception of health was measured using the EQ-VAS at post-treatment (2 weeks). A significant improvement was found on both measures.

Conclusion: There is limited evidence (level 2b) from one quasi-experimental study that aquatic interventions are effective for improving well-being following stroke.

Spasticity
Effective
1b

One high quality RCT (Matsumoto et al., 2016) investigated the effect of aquatic interventions on spasticity in the chronic phase of stroke recovery. This high quality RCT randomized participants to receive aquatic therapy or no aquatic therapy; both groups received conventional rehabilitation. Spasticity was measured using the Modified Ashworth Scale at post-treatment (12 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. no aquatic therapy.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT that aquatic therapy is more effective than no aquatic therapy for reducing spasticity in the chronic phase of stroke recovery.

Strength - lower extremity
Not effective
1a

One high quality RCT (Perez-de la Cruz, 2020) and four fair quality RCTs (Noh et al., 2008; Park et al., 2012; Kum & Shin, 2017; Eyvaz, Dundar & Yesil, 2018) investigated the effect of aquatic interventions on lower extremity strength in the chronic phase of stroke recovery.

The high quality RCT (Perez-de la Cruz, 2020) randomized participants to receive Ai-Chi aquatic therapy, on-land exercises, or combined aquatic therapy + on-land exercises. Lower extremity functional strength was measured using the 30-second chair stand test at post-treatment (12 weeks) and one-month follow-up. No significant between-group difference was found at either timepoint between aquatic therapy vs. on-land exercises.
Note: Significant between-group differences were found at both timepoints in favour of combined therapy vs. aquatic therapy, and in favour of combined therapy vs. on-land exercises.

The first fair quality RCT (Noh et al., 2008) randomized participants to receive aquatic therapy or conventional rehabilitation. Muscle strength was measured using an isokinetic device (knee flexors/extensors – paretic/nonparetic, lumbar flexors/extensors) at post-treatment (8 weeks). A significant difference was found on one measure of muscle strength (paretic knee flexor – change score from baseline to post-treatment), in favour of aquatic therapy vs. conventional rehabilitation.

The second fair quality RCT (Park et al., 2012) randomized participants to receive aquatic treadmill training or land-based treadmill training. Muscle strength was measured using the Short Physical Performance Battery at post-treatment. No significant between-group difference was found.

The third fair quality RCT (Kum & Shin, 2017) randomized participants to receive underwater backward treadmill training or on-ground backward treadmill training. Knee flexor and extensor Isokinetic strength (paretic, non-paretic) was measured by handheld dynamometer (maximal peak torque at 90-degrees/second, 120-degrees/second) at post-treatment (6 weeks). No significant between-group differences were found.

The fourth fair quality RCT (Eyvaz, Dundar & Yesil, 2018) randomized participants to receive water-based exercises or land-based exercises; both groups received additional land-based exercises. Lower extremity muscle strength (paretic, non-paretic sides) was measured at post-treatment (6 weeks). No significant between-group difference was found.

Conclusion: There is strong evidence (level 1a) from one high quality RCT and four fair quality RCTs that aquatic interventions are not more effective than on-land interventions for improving lower extremity strength in the chronic phase of stroke recovery.

Walking endurance
Effective
1b

One high quality RCT (Zhu et al., 2016) and one quasi-experimental study (Morer et al., 2020) investigated the effect of aquatic interventions on walking endurance in the chronic phase of stroke recovery.

The high quality RCT (Zhu et al., 2016) randomized participants to receive hydrotherapy or land-based exercises. Walking endurance was measured using the Two-Minute Walk Test at post-treatment (4 weeks). A significant between-group difference was found, in favour of hydrotherapy vs. land-based exercise.

The non-randomized study (Morer et al., 2020) assigned participants to receive aquatic therapy + thalassotherapy. Walking endurance was measured using the Six-Minute Walk Test at post-treatment (2 weeks). A significant improvement was found.

Conclusion: There is moderate evidence (level 1b) from one high quality RCT that aquatic interventions are more effective than on-land interventions for improving walking endurance in the chronic phase of stroke recovery. A quasi-experimental study also reported improved walking endurance following aquatic therapy.

Walking speed
Effective
1a

Two high quality RCTs (Chu et al., 2004; Matsumoto et al., 2016), three fair quality RCTs (Kim, Lee & Jung, 2015; Kim, Lee & Kim, 2016; Aidar et al., 2018) and one quasi-experimental study (Morer et al., 2020) investigated the effect of aquatic interventions on walking speed in the chronic phase of stroke recovery.

The first high quality RCT (Chu et al., 2004) randomized participants to receive an aquatic lower extremity program or a land-based upper extremity training program. Self-selected gait speed (m/sec) was measured over an 8-meter walking test at post-treatment (8 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. upper extremity training.

The second high quality RCT (Matsumoto et al., 2016) randomized participants to receive aquatic therapy or no aquatic therapy; both groups received conventional rehabilitation. Walking speed was measured using the 10-Meter Walk Test (Speed, Cadence) at post-treatment (12 weeks). A significant between-group difference was found on both measures of walking speed, in favour of aquatic therapy vs. no aquatic therapy.

The first fair quality RCT (Kim, Lee & Jung, 2015) randomized patients to receive aquatic coordination movement using Proprioceptive Neuromuscular Facilitation (PNF) and Neurodevelopmental Therapy (NDT) or NDT alone. Walking speed was measured using the 10-Meter Walk Test at post-treatment (6 weeks). A significant between-group difference was found, in favour of aquatic PNF vs. no therapy.

The second fair quality RCT (Kim, Lee & Kim, 2016) randomized participants to receive aquatic dual-task training or no aquatic therapy; both groups received neurodevelopmental therapy. Walking speed was measured using the 10-Meter Walk Test at post-treatment (6 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. no therapy.

The third fair quality RCT (Aidar et al., 2018) randomized participants to receive an aquatic exercise program or no treatment. Walking speed was measured using the Timed 7.62-Meter Walk test at post-treatment (12 weeks). A significant between-group difference was found, in favour of aquatic therapy vs. no treatment.

The non-randomized study (Morer et al., 2020) assigned participants with chronic stroke to receive aquatic therapy + thalassotherapy. Walking speed was measured using the 10-Meter Walk Test at post-treatment (2 weeks). No significant improvement was found.

Conclusion: There is strong evidence (level 1a) from two high quality RCTs and three fair quality RCTs that aquatic therapy is more effective than on-land interventions or no therapy for improving walking speed in the chronic phase of stroke recovery.

Walking skills
Not effective
2a

One fair quality RCT (Kum & Shin, 2017) investigated the effect of aquatic interventions on walking skills in the chronic phase of stroke recovery. The fair quality RCT randomized participants to receive underwater backward treadmill training or on-ground backward treadmill training. Walking skills were measured using the Figure-of-Eight Walk test at post-treatment (6 weeks). No significant between-group difference was found.

Conclusion: There is limited evidence (level 2a) from one fair quality RCT that aquatic interventions are not more effective than on-land interventions for improving walking skills in the chronic phase of stroke recovery.

Weight-bearing
Effective
2a

Two fair quality RCTs (Noh et al., 2008; Park et al., 2012) investigated the effect of aquatic interventions on weight-bearing in the chronic phase of stroke recovery.

The first fair quality RCT (Noh et al., 2008) randomized participants to receive aquatic therapy or conventional rehabilitation. Weight-bearing ability was measured using an mtd-Balance system (Rising from a chair, Lateral weight-shift, Forward weight-shift, Backward weight-shift – paretic/non-paretic limbs) at post-treatment (8 weeks). A significant difference in change scores from baseline to post-treatment was found on two measures of weight-shift (forward, backward – paretic limb only), in favour of aquatic therapy vs. conventional rehabilitation.

The second fair quality RCT (Park et al., 2012) randomized participants to receive aquatic treadmill training or land-based treadmill training. Weight-bearing ability was measured using the SmartStep System (entire foot, forefoot, hindfoot) at post-treatment. Significant between-group differences were found (entire foot, hindfoot), in favour of aquatic treadmill training vs. land-based treadmill training.

Conclusion: There is limited evidence (level 2a) from two fair quality RCTs that aquatic interventions are more effective than on-land interventions for improving weight-bearing in the chronic phase of stroke recovery.

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Perez-de la Cruz, S. (2020). Comparison of aquatic therapy vs. dry land therapy to improve mobility of chronic stroke patients. International Journal of Environmental Research and Public Health, 17(13), 4728 pp1-12.
DOI: 10.3390/ijerph17134728

Perez-de la Cruz, S. (2021). Comparison between three therapeutic options for the treatment of balance and gait in stroke: a randomized controlled trial. International Journal of Environmental Research and Public Health, 18, 426 pp1-11.
DOI: 10.3390/ijerph18020426

Saleh, M.S.M., Rehab, N.I., & Aly, S.M.A. (2019). Effect of aquatic versus land motor dual task training on balance and gait of patients with chronic stroke: a randomized controlled trial. NeuroRehabilitation, 44, 485-92.
DOI: 10.3233/NRE-182636

Tripp, F. & Krakow, K. (2014). Effects of an aquatic therapy approach (Halliwick-Therapy) on functional mobility in subacute stroke patients: a randomized controlled trial. Clinical Rehabilitation, 28(5), 432-9.
DOI: 10.1177/0269215513504942

Veldema, J. & Jansen, P. (2020). Aquatic therapy in stroke rehabilitation: systematic review and meta-analysis. Acta Neurologica Scandinavica, 43(3), 221-41.
DOI: 10.1111/ane.13371

Xie, G., Wang, T., Jiang, B., Su, Y., Tang, X., Guo, Y., & Liao, J. (2019). Effects of hydrokinesitherapy on balance and walking ability in stroke survivors: a systematic review and meta-analysis of randomized controlled studies. European Review of Aging and Physical Activity, 16, Art. No. 21.
DOI: 10.1186/x11556-019-0227-0

Zhang, Y., Wang, Y-.Z., Huang, L-.P., Bai, B., Zhou, S., Yin, M-.M., Zhao, H., Zhou, X-.N., & Wang, H-.T. (2016). Aquatic therapy improves outcomes for subacute stroke patients by enhancing muscular strength of paretic lower limbs without increasing spasticity: a randomized controlled trial. American Journal of Physical Medicine & Rehabilitation, 95(11), 840-9.
DOI: 10.1097/PHM.0000000000000512

Zhu, Z., Cui, L., Yin, M., Yu, Y., Zhou, X., Wang, H., & Yan, H. (2015). Hydrotherapy vs. conventional land-based exercise for improving walking and balance after stroke: a randomized controlled trial. Clinical Rehabilitation, 30(6), 587-93.
DOI: 10.1177/0269215515593392

Excluded Studies

Lee, J-.Y., Park, J-.S., & Kim, K. (2011). The effect of aquatic task training on gait and balance ability in stroke patients. The Journal of Korean Society of Physical Therapy, 23(3), 29-35.
Reason for exclusion: Between-group differences were not reported.

Lim, C-.G. (2020). Effect of underwater treadmill gait training with water-jet resistance on balance and gait ability in patients with chronic stroke: a randomized controlled pilot trial. Frontiers in Neurology, 10: 1246.
Reason for exclusion: Both groups received a form of aquatic treadmill training.

Park, B-.S., Noh, J-.W., Kim, M-.Y., Lee, L-,K., Yang, S-.M., Lee, W-.D., Shin, Y-.S., Kim, J-.H., Lee, J-.U.., Kwak, T-.Y., Lee, T-.H., Kim, J-.Y., Park, J., & Kim, J. (2015). The effects of aquatic trunk exercise on gait and muscle activity in stroke patients: a randomized controlled pilot study. Journal of Physical Therapy Science, 27, 3549-53.
Reason for exclusion: No between-group comparisons.

Temperoni, G., Curcio, A., Iosa, M., Mangiarotti, M.A., Morelli, D., De Angelis, S., Vergano, S., & Tramontano, M. (2020). A water-based sequential preparatory approach vs. conventional aquatic training in stroke patients: a randomized controlled trial with a 1-month follow-up. Frontiers in Neurology, 11: 466.
Reason for exclusion: Both groups received a form of aquatic training.

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