"Ah, im just doing a recovery ride!". How often do you hear fellow cyclist say that? Recovery rides are essential and now part of a well laid out training plan, but people seem to do it plain wrong. This is really a case of keeping the easy days easy, which as been lost in translation among the cycling community, especially for folks riding on HR or feel.
These kind of rides are supposed to be short and easy. When I say easy, I mean boring easy, granny passing you on the bike path easy, 39/36 gearing style. Got it? Anyone who passed me yesterday on the bike path must have told themselves "geeeezz he's either very unfit or having a flat tire!!". Indeed, a 140 watts ride means you go overly slow, just turning the legs and refreshing your body, both physically and mentally.
Recovery rides are not uspposed to induce further stress and are meant to favour vasoconstriction in the working muscle to move blood arround without stressing your body further more. Blood is your nutrient and waste carrier. Increasing blood flow in the working muscle helps removing metabolic wastes and distribute nutrients more effectively. As a bonus, going out on the bike on a sunny day is easier on your mental health then sitting on the couch and having an off day.
I generally make sure I stay arround 50% FTP during my recovery rides and use a pretty flat course. If any hills are involved during the ride, I make sure I climb them very slowly, even though it might mean climbing in the 26/34 gear, I dont care. I also try to keep cadence relatively steady and fast, arround 90-100 RPM.
Most people think they are doing easy spins and recovery rides, yet they overshoot intensity, spike power on hills or headwind and climb too fast to make it a real recovery ride. They'd be better off sitting on the couch then screwing their only recovery days. I think you only realize how piss slow a recovery ride is when you start riding with power, among many other things a powermeter will make you realize.