I've got a good backlog of stories, hopefully I'll get a chance to write more soon, and I'm working on several new projects. One of them is bike technology related--a pulse oximeter you can wear while riding.
I started looking into that after climbing a hill here in Nashville--Riverside Road in East Nashville. It climbs up from the Cumberland River at a maximum 17% grade. It's a short climb, so you can sprint, but whenever I would, I'd be completely wiped out and hyperventilating by the top.
I went and bought a cheap pulse oximeter at a drug store and did the ride again. The pulse oximeter is a gizmo that clips onto your fingertip and estimates O2 saturation by measuring the absorption of red and infrared light. For a healthy person, the O2 saturation is essentially 100% all the time. When I did the climb again, anaerobic, but not at full gas, I measured the O2 saturation at the top of the hill and, sure enough, it was down to 93%. That got me thinking it would be a good complimentary piece of training data. Maybe it's possible to directly measure VO2 max, for example. So, I've been messing around building a prototype for the past few months. It's going to be tricky to engineer something that will work as reliably as a heart rate monitor.