5 Exercises to Flatten Your Stomach and Reduce Low-back Pain - https://www.acefitness.org/blog/3092...nd-reduce-low/
Bibliography
1. Relieve Back Pain With Core Strength Training, by Gina Shaw and Michael W. Smith, MD
2. ACE Kick-Start Workout - American Council On Exercise
3. Various articles and newsletters, American Council on Exercise (ACE)
Bookmarks