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tency of results into account, there is level B evidence
for improved walking independence after repetitive
gait training.
• Walking speed: This was assessed in 9 RCTs and
pooling yielded a non-significant homogenous SES
(9 RCTs; n = 672 [exp 342; ctr 330]; MD = 0.05
[fixed]; 95% CI –0.00 to 0.11; p = 0.06; I 2 = 42%). No
significant subgroup difference was found (p = 0.41).
• Walking endurance: In 4 RCTs, endurance was mea-
sured. When pooling data, a significant homogenous
SES (4 RCTs; n = 406 [exp 206; ctr 200]; MD = 24.36
[fixed]; 95% CI 3.58–45.14; p = 0.02; I 2 = 43%) is
found. Taking the inconsistency of results into ac-
count, there is level B evidence for improved walking
endurance after repetitive gait training. If pooling
end-effector trials only, a homogeneous significant
SES is calculated (3 RCTs; n = 309 [exp 154; ctr 155];
MD = 32.08 [fixed]; 95% CI 8.30–55.86; p = 0.008;
I 2 = 44%).
Body function level:
• Motor control: Four RCTs assessed the FM-L and
pooling results yielded a non-significant homo-
geneous SES (4 RCTs; n = 179 [exp 91; ctr 88];
MD = 0.52 [fixed]; 95% CI –1.52 to 2.59; p = 0.62;
I 2 = 28%). If pooling exoskeleton trials only, a non-
significant heterogeneous SES is calculated (3 RCTs;
n = 119 [exp 63; ctr 56]; MD = 0.76 [fixed]; 95% CI
–1.83 to 3.36; p = 0.56; I 2 = 51%).
• Muscle strength: For a comparison on the MI-L,
results of 5 RCTs could be pooled. This resulted in a
non-significant heterogeneous SES (5 RCTs; n = 364
[exp 185; ctr 179]; MD = 3.64 [random]; 95% CI –2.88
to 10.17; p = 0.27; I 2 = 56%). If isolating effects of
end-effector trials a significant homogeneous SES (3
RCTs; n = 230 [exp 113; ctr 117]; MD = 8.00 [random];
95% CI 2.08–13.93; p = 0.008; I 2 = 8%) is identified.
DISCUSSION
No between-group difference in the occurrence of
adverse events and drop-outs was found despite the
demanding nature of the intervention. This suggests
it is feasible to provide repetitive training early after
stroke by the use of an overhead harness system for
support of body weight and manual or electromecha-
nical assistance in forward progression of the paretic
leg. Statistical significant effects on walking indepen-
dence (at follow-up) and endurance is found in favour
of repetitive training, according to level B evidence.
Sub-analyses revealed that these effects are based
mainly on studies investigating RAGT provided with
an end-effector robot.
www.medicaljournals.se/jrm
Dose-response relation in stroke rehabilitation
In the context of neurological rehabilitation, repetitive
training leads to task-specific improvements (10, 31)
and associated neuroplastic re-organization (50) if a
sufficient dose of practice is provided. In animal mo-
dels, synaptic changes in the motor cortex are observed
after 400, but not after 60 reach-movements (51) and
gait training is effective only if at least 1,000 steps are
performed during a treadmill session (52). Correspon-
ding findings in clinical research are in favour of a
dose-response relation in stroke rehabilitation (17, 53).
Despite this solid association between larger quantities
of practice and greater gains, inpatient rehabilitation
is described as a time of being physically inactive (54,
55) and the practice dose is far less than is provided in
previously mentioned stroke models: patients walked
for a mean of 250 (21) steps, while non-ambulatory
patients walked for as little as 6–16 steps (56) during
a therapeutic session aiming at gait recovery.
Technological advances can be of great value in
providing more intensive rehabilitation, as robots let
non-ambulatory patients train at much higher doses
(57). For example, the Gait Trainer allows patients to
execute approximately 1,000 steps in a session, while
assistance of a single therapist is usually sufficient (35,
39, 43). In line with a dose-response relation, training
with such a device appears effective in improving
walking independence and endurance. This implies
the importance of practice repetitions when designing
effective interventions (58) and, in more general terms,
the significance of motor learning in stroke rehabilita-
tion (14, 50, 59).
However, the dose-response relationship is not
linear, indicating that other factors have an influence
(53). Morone et al. (43, 44) compared responsiveness
to training between groups who differ in baseline sco-
res on the MI-L (MI-L≈16 vs 52). Outcomes clearly
demonstrate that only the more impaired patients be-
nefit (43, 44), which is supported by Pohl et al. (35)
as they found impressive effects in a more affected
population (MI-L≈32; see Table II). Interestingly, the
initial muscle strength of the paretic leg (e.g. assessed
with the MI-L (6)) measured within the first days to
weeks post-stroke is associated with walking ability
at 6 months (5, 6, 60). Therefore, it appears that robot-
assisted training was most effective in those patients
with a poor prognosis. This might be related to a greater
treatment contrast, since the more affected patients do
not engage in intensive rehabilitation under conven-
tional conditions (56). As suggested by Morone et al.
(57) future research should not investigate if RAGT is
effective, but rather who may benefit (43, 57).