Figure 2From: Interval exercise versus continuous exercise in patients with moderate to severe chronic obstructive pulmonary disease – study protocol for a randomised controlled trial [ISRCTN11611768]The upper graph shows the continuous exercise protocol for a patient who achieved a maximum exercise capacity of 100 Watts during a usual incremental exercise test. The lower graph shows the interval exercise protocol for a patient who achieved a short time muscular exercise capacity of 200 Watts during a steep ramp test.Back to article page