As women enter their 40s and beyond, hormonal changes can make it harder to build muscle, maintain energy, and manage body composition. High-intensity training is one of the most powerful tools for ...

When it comes to zone 2 vs HIIT training, it feels like there’s a new study published every other week about which method trumps the other for fitness. So, we consulted the experts for their final ...

Do you even know what HIIT stands for? We have the answer to that—and more.

Julia Sullivan is a health and fitness writer, editor and content strategist well as a certified personal trainer. Her byline is in many publications from Harper's Bazaar to SELF Magazine to brand ...