This is one even I could do (and need to!) – even though I much prefer being outdoors.
Some fitness fads come and go, but others, like yoga or Pilates, aren’t going away anytime soon. Another trend that’s definitely here to stay? High-intensity interval training, or HIIT, which involves short bouts of extreme effort alternated with periods of rest. “HIIT workouts are quick and dirty, never lasting more than 30 minutes including a warm-up and short cool-down,” explains Gina Harney, certified personal trainer and creator of Fitnessista.com. “You’re working as hard as possible for a short amount of time and then reaping the rewards throughout the day.”