Interval exercise is well tolerated in people with chronic lung disease

doi:10.1136/bmj.333.7581.1265-a

BMJ 2006;333:1265 (16 December), doi:10.1136/bmj.333.7581.1265-a

Practice

Short cuts

Interval exercise is well tolerated in people with chronic lung disease

View larger version (58K):
[in this window]
[in a new window]
[PowerPoint Slide for Teaching]

High intensity exercise improves quality oflife for people with severe chronic obstructive pulmonary disease,but it can be hard to tolerate. Interval exercise, which switchesbetween high and low intensity, works just as well accordingto a head to head trial from Switzerland.

Ninety eight men and women with severe pulmonarydisease undertook a three week rehabilitation programme including15 sessions of continuous high intensity or interval exerciseon a bicycle ergometer. Improvements in quality of life andexercise capacity as measured by the six minute walking testwere similar in both groups (difference between continuous andinterval groups 1.1 m, 95% CI –25.4 to 27.6). But thosedoing the interval exercise were less likely to drop out (52.1%v 76%, P=0.014) and needed fewer unscheduled breaks (median2 v 11, P=0.023).

The researchers deliberately designed theirtrial to test whether interval exercise was "non inferior" tointensive exercise, and it was. So doctors and patients cannow choose their preferred programme, knowing that both workwell but one is easier than the other.

In this study, patients doing continuous exerciseworked at 70% of their maximum capacity for 20 minutes at atime. Patients in the interval group worked more intensively,but only for 20 seconds out of each minute. They spent the other40 seconds recovering.