A common belief is that you should use light weights and complete a high number of repetitions if your desire is to "tone," and use heavy weights and perform a low number of repetitions if your goal is to "bulk up". ACE's Jessica Matthews explains what you really need to know to reach your goals.

Author
Jessica Matthews
Health and Fitness ExpertJessica Matthews, M.S., E-RYT500 is faculty in kinesiology and integrative wellness at Point Loma Nazarene University and professor of yoga studies at MiraCosta College, where she helps to grow and mentor the next generation of health and wellness professionals. A dynamic speaker, respected educator, fitness industry veteran and featured wellness expert, Jessica is a trusted and recognized go-to media resource, regularly contributing to numerous publications and outlines on topics ranging from fitness and yoga, to health coaching and career development. Additionally, she serves as ACE’s senior advisor for health and fitness education, and is the lead editor and author of the ACE Group Fitness Instructor Handbook: The Professional’s Guide to Creating Memorable Movement Experiences. You can connect with her at www.jessica-matthews.com, @fitexpertjess (Twitter and Instagram) and www.facebook.com/fitexpertjess.