When properly performed, the plank (A), side plank (B), and bird dog (C) exercises above are effective and safe methods for developing core strength. Note the neutral position of the spine (ie, no flexion or extension) in all three exercises.
Reproduced with permission from: Moir G, Bladen TL. Kinesiology, anatomy, and biomechanics. In: ACSM's Resources for the Group Exercise Instructor, DeSimone G (Ed), Lippincott Williams & Wilkins, Philadelphia 2011. Copyright © 2011 Lippincott Williams & Wilkins.
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