Sprint interval training, or SIT, is super trendy right now. It’s a great way to improve your running speed and to get in a hard interval workout, and I’ll explain exactly how. But I also need to ...

HIIT, or high-intensity interval training, is increasingly popular, and it provides plenty of benefits, from torching calories to increasing your VO2 max and overall athletic performance. SIT, or ...

As HIIT's popularity soars, sprint interval training, or SIT, is doing its best to catch up. Can shorter, harder, faster deliver better results? As the popularity of HIIT continues to soar, sprint ...

For those who live to sweat — but maybe want a chance to fully catch their breath — SIT is the new HIIT. HIIT, or high-intensity interval training, includes bursts (typically 30 seconds to a few ...

Beth Skwarecki is Lifehacker’s Senior Health Editor, and holds certifications as a personal trainer and weightlifting coach. She has been writing about health for over 10 years. Sprint interval ...