Exploring adaptations to the modified shuttle walking test

ABSTRACT

Objective: The 10 m modified shuttle walking test

(MSWT) is recommended to determine the functional

capacity in older individuals and for patients entering

cardiac rehabilitation. Participants are required to

negotiate around cones set 1 m from the end markers.

However, consistent comments indicate that for some

individuals manoeuvring around the cones can be

quite difficult. Therefore, the objective of this study

was to explore differences within and between noncardiac

and postmyocardial infarction (MI) males

during MSWT with and without the cones.

Design: Comparative study.

Participants: 20 post-MI (64.8±6.6, range

51–74 years) and 20 non-cardiac male controls

(64.1±5.7, range 52–74 years) participated.

Methods: Participants performed MSWT with and

without cones. Throughout, the participants expired

air, and the heart rate (bpm) (HR) and ratings of

perceived exertion (RPE) were measured. Participant

protocol preference was recorded verbatim.

Results: One-way analysis of variance found no

significant difference in VO2 peak (cones 20.4±5.1 vs nocones

21.9±4.8 ml/kg/min, p=0.197) or distance ambulated

(cones 631.8±132.9 m vs no-cones 662.4±164.1 m,

p=0.371) between protocols or groups. Analysis comparing

lines of regression showed a significant trajectory difference

in VO2 (ml/kg/min) (p<0.01) between protocols with higher

HR (p<0.01) and respiratory exchange ratio (RER, p<0.001)

values during cones. RPEs were higher for post-MIs versus

controls during both protocols (p<0.05). Post-MIs taking

?-blockers produce significantly lower HR values. The ?2

analysis found no significant difference in protocol

preference (no-cones: all n=25, 63%; post-MIs n=13, 65%;

and controls n=12, 60%).

Conclusions: Post-MIs found both protocols

subjectively harder than controls with no significant

difference in the VO2 peak. However, both groups worked

at a lesser percentage of their anaerobic threshold during

no-cones protocol as indicated by lower RER values.

Importantly, for the post-MIs, this would reduce their risk

of functional impairment. Therefore, though more

research is required, indicators at present are more

favourable for the use of the no-cones with post-MIs.