Did you miss a workout? It's OK. Taking a rest day is actually highly recommended and essential for your recovery and muscle building!

It's important to know that missing a workout here and there isn't going to derail you, unless you let it. In fact, we got a great pep talk from Tone It Up trainers Karena Dawn and Katrina Scott. Karena told POPSUGAR to dive back in as quickly as possible.

 "It's all about how you recover [from missing a workout], too," Katrina added. "If we have a bad week where we really couldn't get anything in . . . it's almost like we keep going because we think we already screwed up." How do you keep yourself from that? "If you miss a workout, you can't beat yourself up. Just get back out there and get your workout in the next day."

So now that we've got that out of the way, what happens physically when we miss these workouts? The short answer: it depends on what your workout schedule is usually like. We got the scoop on the physiology — and the timeline breakdown — from Liz Letchford, MS, ATC, PhD candidate, and personal trainer at DIAKADI. She calls a period of missed workouts "detraining."

 It turns out that weight trainers have the greatest risk of losing strength over time. "With isometric training not including high-intensity exercise (classic weightlifting), strength loss can occur at a rate of 0.3-percent to 0.8-percent per week," she told POPSUGAR through email.

  But those who have more of a cardio schedule typically keep their strength even when they take time off. Also of note, the more advanced you are, the more you have to lose. "Those who are highly trained show a greater magnitude of strength loss when compared to untrained or moderately trained individuals."