There are two major reasons to swap out the headphones that came packaged with your MP3 player. The first is sound quality, and the second is fit. The two are not mutually exclusive, but you may place emphasis on one over the other depending on your device usage. If you mainly use your MP3 player at the gym, getting a pair of headphones that both fit securely and offer some sweat resistance is key. The $40 Nike Aero Sport Headphones certainly fit the bill there, and although music doesn't sound great through this set, the sleek and sweatproof design may appeal to some.
The Nike Aero Sport Headphones are sold in the Apple Store, and they fit in excellently. Two sleek white, shiny plastic discs contain flat speaker drivers that rest on the outside of the ear. These are attached by a thin, plastic neckband that loops over the top of the ear and then behind the head. A single thin white cable extends from the middle of the neckband so that you may keep the cord behind your arms during activity. Nike also includes a disc-shaped shirt clip for further cable management. Overall, it's a sleek and stylish design that will appeal to those who appreciate the Apple aesthetic.
A few of the other physical aspects of the Aero Sport headphones are worth calling out. The first is that although the set fits very securely during vigorous activity, the hard plastic of the ear loops isn't particularly comfortable and tended to chafe our ears after about 30 minutes of wear. On the plus side, the earphones are extremely sweat-resistant and easy to clean thanks to their plastic design and rubber earpads. Also, we like that they don't block out outside noise, since that makes them appropriate for street-runners as well as gym-goers.
Unfortunately, the actual sound quality offered by the Aero Sport headphones is far from impressive. High-end details are muted, bass is lacking, and mids are exceptionally forward. It sounds like someone took the EQ and adjusted it heavily toward the middle range. However, music is at least clear with no distortion, and spoken word audio comes through just fine. Really, excellent sound quality may not be a consideration if you're just using the headphones for the gym anyway. We don't recommend the Aero Sport headphones for day-to-day use, but for $40, they're a solid option for working out.