To get a heart rate reading, the UltraTread pairs with the Apple Watch (the only fitness tracker it's currently compatible ...

That tension becomes especially clear with heart rate zone training, a popular five-tier system that endurance athletes use to measure effort and fine-tune performance. The well-known formula is ...

As the weather starts getting colder, chances are you're looking for ways to stay active indoors. Perhaps you've got the itch to run your first 5K, 10K, half or full marathon in the upcoming year, so ...