This "squishiness," George clarifies, "permits the user to wedge it guiding their back for core work or squeeze driving their knee for glute exercises. Should the ball is too stiff, it can be tough to hold onto or place your body in awkward angles and positions." Toughness coach and chiropractor https://advertisesmart.com/view/post/How-to-Relieve-Sciatica-with-Targeted-Exercises/96