Most earbuds are designed for use while mobile; after all, they're inherently more portable and discrete than headphones. But not all of them are made for heavy activity. Ever try running or hitting the gym with most off-the-shelf 'buds? I have, for years. It's usually not an enjoyable experience. They need to meet some pretty specific criteria:
- The earbuds need to stay put at all times. Any regular fitness fan will tell you that getting in a sort of rhythm is pretty important, and it's nigh-impossible to do so if you're stopping every few minutes to fix your earbuds.