The first time that I went to our gym I did 20 minutes on an indoor stationary bike and 20 minutes on a treadmill. And like a lot of others, I saw virtually no movement in the lovely green Exercise ring. I selected Indoor Cycle for the bike and Indoor Run for the treadmill.
Today, I did 45 minutes on the on just the Indoor Cycle and low and behold I was credited with 45 minutes of "exercise". The only difference this time is that my iPhone was not nearby - I left it in the locker room. (Though I never saw the red "I can't find your iPhone" indicator on the Watch.)
What I did notice is that when I swiped through the various screens of the Activity app, there was ones for Time, Calories and Heart Rate - not for distance (duh, was not moving anyway). The first time that I did the stationary bike, I had the iPhone in my pocket and the distance screen was there. So perhaps the issue with at least stationary bikes is if the iPhone is nearby, the Watch is trying to use the GPS on the phone - like you were riding a real bike on an indoor track - and since it sensed no actual movement, it did not credit it as "exercise" even though my Heart Rate was up. (And no, I was not swinging my left arm to simulate movement.)
Today, I did 45 minutes on the on just the Indoor Cycle and low and behold I was credited with 45 minutes of "exercise". The only difference this time is that my iPhone was not nearby - I left it in the locker room. (Though I never saw the red "I can't find your iPhone" indicator on the Watch.)
What I did notice is that when I swiped through the various screens of the Activity app, there was ones for Time, Calories and Heart Rate - not for distance (duh, was not moving anyway). The first time that I did the stationary bike, I had the iPhone in my pocket and the distance screen was there. So perhaps the issue with at least stationary bikes is if the iPhone is nearby, the Watch is trying to use the GPS on the phone - like you were riding a real bike on an indoor track - and since it sensed no actual movement, it did not credit it as "exercise" even though my Heart Rate was up. (And no, I was not swinging my left arm to simulate movement.)