6-min walk work
The 6-min walk work is the product of 6MWD and body weight, which may provide a better estimation of
the work required to perform the test than distance alone. The 6MWD6weight product correlates more
strongly with DLCO and V9O2peak than 6MWD alone [63, 64]. To date, no studies have investigated the
sensitivity of 6MWD6weight product to change over time. Additional studies are needed to better
characterise the utility of the 6-min walk work in adults with respiratory disease.
In summary, the 6MWD is the primary outcome of the 6MWT and should be recorded on every test. The
SpO2 and HR should be measured continuously during the 6MWT, to ensure that the lowest SpO2 and the
end-test HR are recorded. Care should be taken that obtaining these measures does not affect performance.
Current data indicate that the 6MWT has an excellent safety profile when the test is stopped if SpO2 falls to
,80%; few data are available to define the safety profile if desaturation to ,80% is permitted. Dyspnoea
and subjective fatigue should be measured before and after the 6MWT.leg muscles has been reported to be greater in COPD patients compared with controls