It’s 2019, which means you almost definitely already own a pair of Bluetooth earbuds. But I submit that you should actually have a second, spare pair that can live in your luggage or gym bag, for when you inevitably forget your favorites at home.
This pair from TaoTronics is sweatproof, magnetic, and most importantly of all, runs for nine hours on a charge, which is about as good as it gets for wireless earbuds. Not bad for $16 (with code KINJA26V).