Those randomised to receive the online programme will be loaned a computer/tablet for the six-week duration, given log-in details and a password, and instructions to begin the programme at home. A further visit to these participants home may need to be arranged to ensure that the Internet connection is suitable. If the internet connection is unsuitable, the participant will be withdrawn from the study and referred to the NHS PR. The online programme mirrors the conventional face-to-face PR programme and the exercise and educational components are given by means of instructional videos. Participants will be instructed to exercise five times a week. Participants in the online arm will receive during the PR course telephone contact to record any adverse or serious adverse events. They will be contacted twice during the first 2 weeks, then weekly for the remaining 5 weeks.