My 1,000th attempt at this and I started at Week 3 tonight to ease myself in. Set the mph to 8.0 for the 90 second runs and 7.5 for the 3 minute ones and feel absolutely fine. Only started struggling in the last 2 minutes of the final run. I know it'll be frustrating for the next 3 weeks or so but I need to build my stamina slowly so that I can get back to doing 20 minute runs and losing weight again
Thanks for all your support!