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. Almost every gym I’ve ...

In the world of high-performance fitness, most people waste hours arguing about "fat-burning zones" while completely ignoring the only metric that truly removes body fat: total energy expenditure over ...

Q: I got into a discussion the other day about the lenght of intervals. This program has as you know one interval of 30 seconds and one of 1 minute (I am just finishing week 2 and those have been the ...

If you follow the run/walk method, you know alternating run and walk intervals can save energy and ultimately improve your overall pace. And if you progress those run/walk intervals the right way, you ...

There are all types of cycling intervals under the sun, including short Tabata-style intervals of repeated on-off efforts which have become popular. How effective are they compared to longer, steady ...

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. If we were to say the word ‘interval’ to you, what would your first thought be? The theatre? Ice ...