If it’s a solo road ride, like a commute, or just getting some miles in, I’ll often have music. Picking songs with the right tempos can also help you hold a particular pace or cadence.
When I do, it’s only one ear, usually the curb side, depending if I’m riding or running.
If its any any kind of group (2 or more) or a high traffic situation, like downtown, then I’ll ditch the headphones.
The pair i use for cycling has has an over-the-ear hook, so it doesn’t need to seal tightly, and the volume/pause controls are right on the pod, so I don’t need to fumble around for a cord or the phone to turn it down or off. (Or louder
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